HK1261281A1 - Polymeric foam comprising low levels of brominated flame retardant and method of making same - Google Patents

Description

Polymer foams containing low levels of brominated flame retardants and methods of making the same

RELATED APPLICATIONS

Priority and any other benefit of U.S. provisional patent application No. 62/334511 entitled "polymer foams containing low levels of brominated flame retardants and methods for making same" filed 2016, 5, month 11, the entire disclosure of which is incorporated herein by reference in its entirety.

Background

Flame retardants are often added to flammable and combustible materials to reduce or prevent damage due to fire. Flame retardants are particularly important in flammable materials used in construction and construction, building insulation, indoor cloth decorations, clothing, and the like because of the serious risk of fire causing damage, injury, and death to people, animals, and property.

One class of flame retardants commonly used in polymeric materials includes non-polymeric brominated compounds, such as Hexabromocyclododecane (HBCD). It is of general interest to reduce the amount of bromine used in flame retardant compositions and combustible materials treated with flame retardant compositions.

Summary of The Invention

Various exemplary embodiments of the present invention are directed to compositions and methods for preparing polymeric foams. The polymer foam includes a flame retardant composition comprising at least one brominated polymer. The flame retardant composition may comprise one or more flame retardant components. The resulting polymer foam has a reduced bromine content while maintaining acceptable flame retardant properties. In some exemplary embodiments, the flame retardant composition comprises a stabilizer. In some exemplary embodiments, the flame retardant composition comprises a synergist.

In some exemplary embodiments, foamable polymer mixtures are disclosed. The foamable polymer mixture comprises a polymer composition, a blowing agent composition, and a flame retardant comprising a brominated polymer. The foamable polymer mixture contains about 0.01 to 0.5 wt% bromine.

In some exemplary embodiments, a method of making a polymer foam is disclosed. In some exemplary embodiments, the method of making the polymeric foam is by an extrusion process. The method includes introducing a polymer composition into a screw extruder to form a polymer melt, and introducing a flame retardant composition comprising a brominated polymer into the polymer melt. Injecting a blowing agent into the polymer melt to form a foamable polymer material, and extruding the foamable polymer material to form an extruded polymer foam. The extruded polymeric foam contains about 0.01 to 0.5 weight percent bromine.

In some exemplary embodiments, extruded polymeric foams are disclosed. An extruded polymeric foam includes a polymeric material, a flame retardant composition comprising a brominated polymer, and a blowing agent composition. The extruded polymeric foam contains about 0.01 to 0.5 weight percent bromine.

In some exemplary embodiments, a method of making a polymer foam is disclosed. In some exemplary embodiments, the method of making the polymer foam comprises an expansion foaming process. The expansion foaming process involves introducing a monomer dispersed in a liquid phase into a reaction vessel. A flame retardant composition comprising a brominated polymer and a blowing agent composition is also introduced into the reaction vessel. The monomers are polymerized to form the polymer. The polymer is expanded to form an expanded polymer foam. The expanded polymeric foam contains about 0.01 to 0.5 weight percent bromine.

In some exemplary embodiments, expanded polymeric foams are disclosed. The expanded polymeric foam includes a polymeric material derived from monomers polymerized to form a polymer, a flame retardant composition comprising a brominated polymer, and a blowing agent composition. The expanded polymeric foam contains about 0.01 to 0.5 weight percent bromine.

Detailed Description

Polymer foam compositions and methods of making polymer foams are described in detail herein. The compositions and methods of making polymer foams disclosed herein include flame retardant compositions comprising brominated polymers. The resulting polymer foam has a reduced bromine content while maintaining acceptable flame retardant properties. In some exemplary embodiments, the flame retardant composition comprises a stabilizer. In some exemplary embodiments, the flame retardant composition comprises a synergist. These and other features of the polymer foam, as well as many optional variations and additions, are described in detail below.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. Any reference cited in this disclosure, including published or corresponding U.S. or foreign patent applications, issued U.S. or foreign patents, or any other references, is hereby incorporated by reference in its entirety, including all data, tables, figures, and text presented in the cited references.

The numerical ranges used in this invention are intended to include each number and sub-set of numbers within the range, whether or not specifically disclosed. Furthermore, these numerical ranges should be construed to provide support for claims directed to any number or subset of numbers within the range. For example, a disclosure of 1-10 should be interpreted to support a range of 2-8,3-7,5-6,1-9,3.6-4.6,3.5-9.9, and so forth.

All references to singular features or limitations of the present disclosure shall include the corresponding plural features or limitations, and vice versa, unless otherwise indicated or clearly implied by the context of the reference.

Unless otherwise indicated, the values of components or ingredients of the polymeric foam, flame retardant composition, or other composition used in the present invention are expressed as weight percent or wt% of each ingredient in the composition. The values provided include the maximum and include the given endpoints. Unless otherwise indicated, the terms "wt%" and "wt%" are used interchangeably and denote a percentage of 100% based on the total weight of all ingredients except the weight or wt% of the blowing agent composition.

As used herein, "theoretical bromine content" refers to the calculated bromine content of the foamable polymer mixture (i.e., the mixture prior to foaming), expressed as a weight percent, based on the total weight of the foamable polymer mixture (excluding the weight of the blowing agent composition). The theoretical bromine content is equal to the weight percent of brominated polymer in the foamable polymer composition multiplied by the weight percent of bromine of the brominated polymer.

As used herein, "actual bromine content" refers to the bromine content as measured in the polymer foam after foam preparation. The actual bromine content can be determined by standard test methods known to those skilled in the art, such as X-ray fluorescence spectroscopy (XRF).

The present general inventive concept relates to polymer foam compositions and methods of making polymer foams that include flame retardant compositions comprising brominated polymers, wherein the polymer foams have reduced bromine content compared to the bromine content of other known polymer foams that include flame retardants, while still achieving acceptable flame retardant performance. In some exemplary embodiments, the flame retardant composition comprises a stabilizer. In some exemplary embodiments, the flame retardant composition comprises a synergist.

Matrix polymer

The matrix polymer forms the bulk of the foamable polymer mixture and provides strength, elasticity, toughness and durability to the final product. The base polymer is not particularly limited, and in general, any polymer capable of foaming may be used as the base polymer in the foamable polymer mixture. The matrix polymer may be a thermoplastic or thermoset polymer. In some embodiments, the matrix polymer may comprise a single polymer. In some embodiments, the matrix polymer may comprise a blend of two or more polymers. In some embodiments, the matrix polymer may be selected to provide sufficient mechanical strength to the final polymer foamed product. In some embodiments, the matrix polymer may be selected to be compatible with the process used to form the final polymeric foam product. In some embodiments, the matrix polymer is chemically stable, i.e., generally non-reactive, over the expected temperature range experienced during its formation and subsequent use in the polymer foam.

The matrix polymer may be present in the foamable polymer mixture in an amount of at least about 50 wt% (based on the total weight of all ingredients except the blowing agent composition), from about 60 to 100 wt%, from about 70 to 99 wt%, from about 75 to 98 wt%, from about 80 to 96 wt%, or from about 85 to 95 wt%. In certain exemplary embodiments, the matrix polymer may be present in an amount of about 80 to 100 wt%.

The term "polymer" as used herein is a generic term for the terms "homopolymer", "copolymer", "terpolymer", and combinations of homopolymers, copolymers, and/or terpolymers. Non-limiting examples of suitable foamable polymers include alkenyl aromatic polymers, styrenic polymers, Polystyrene (PS), styrenic copolymers, styrenic block copolymers, copolymers of styrene and butadiene, Styrene Acrylonitrile (SAN), acrylonitrile butadiene styrene, acrylic/styrene/acrylonitrile block terpolymer (ASA), styrene maleic anhydride copolymer (SMA), styrene methyl methacrylate copolymer (SMMA), polyolefins, Polyethylene (PE), polypropylene (PP), copolymers of ethylene and propylene, copolymers of vinyl acetate and ethylene, polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), polycarbonates, polyisocyanurates, polyesters, polyethylene terephthalate (PET), polyacrylates, polymethyl methacrylate (PMMA), polyphenylene oxide, styrene copolymers, styrene, Polyurethanes, phenolic resins, polysulfones, polyphenylene sulfides, acetal resins, polyamides, polyaramides, polyimides, polyetherimides, rubber modified polymers, thermoplastic polymer blends, and combinations thereof.

In some exemplary embodiments, the matrix polymer is an alkenyl aromatic polymer material. Suitable alkenyl aromatic polymer materials include alkenyl aromatic homopolymers and copolymers of alkenyl aromatic compounds with copolymerizable ethylenically unsaturated comonomers. In addition, the alkenyl aromatic polymer material may include minor amounts of non-alkenyl aromatic polymers. The alkenyl aromatic polymer material may be formed from one or more alkenyl aromatic homopolymers, one or more alkenyl aromatic copolymers, blends of one or more of each of the alkenyl aromatic homopolymers and copolymers, or blends thereof with non-alkenyl aromatic polymers.

Examples of alkenyl aromatic polymers include, but are not limited to, alkenyl aromatic polymers derived from alkenyl aromatic compounds such as styrene, Styrene Acrylonitrile (SAN) copolymer, α -methylstyrene, ethylstyrene, vinylbenzene, vinyltoluene, chlorostyrene, and bromostyrene.

In certain exemplary embodiments, minor amounts of monoethylenically unsaturated monomers, such as C2-C6 alkyl acids and esters, ionomeric derivatives, and C4-C8 dienes, may be copolymerized with the alkenyl aromatic monomers to form the alkenyl aromatic polymers. Non-limiting examples of copolymerizable monomers include acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, itaconic acid, acrylonitrile, maleic anhydride, methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, methyl methacrylate, vinyl acetate, and butadiene.

In certain exemplary embodiments, the matrix polymer may be formed entirely of polystyrene. In certain exemplary embodiments, the matrix polymer may be formed substantially (e.g., greater than 95 wt%) from polystyrene. In certain exemplary embodiments, the matrix polymer may be formed from about 40 to 100 wt% polystyrene, including about 45 to 99 wt%, including about 50 to 98 wt%, including about 55 to 97 wt%, including about 60 to 96 wt%, including about 65 to 95 wt%, including about 70 to 94 wt%, including about 75 to 93 wt%, including about 80 to 92 wt%, including about 85 to 91 wt%, including about 80 to 90 wt% polystyrene.

Flame retardant composition

The foamable polymer mixture of the invention also comprises a flame retardant composition comprising a brominated polymer. The foamable polymer mixture contains an amount of flame retardant composition such that the bromine content in the foamable polymer mixture is from about 0.01 to 0.5 weight percent (based on the total weight of all ingredients except the blowing agent composition). In some exemplary embodiments, the flame retardant composition may be added during the preparation of the extruded polymeric foam to impart flame retardant properties to the extruded polymeric foam. In some exemplary embodiments, the flame retardant composition may be added during the preparation of the expanded polymeric foam to impart flame retardant properties to the expanded polymeric foam.

Flame retardant compositions comprising brominated polymers can replace HBCD. Brominated polymers have been tested and found to be more sustainable than HBCD because they are not bioaccumulating or toxic. HBCD has a molecular weight of 642Da, while brominated polymers have a higher molecular weight (i.e., greater than about 10 kDa). Higher molecular weight means that the brominated polymer will not bioaccumulate if ingested, inhaled, or absorbed by a human or animal. The bromine content of HBCD is typically about 75 wt% of the total weight of HBCD. In contrast, the brominated polymers used in the flame retardant compositions of the present invention typically have a bromine content of about 60 to 66 weight percent of the total weight of the brominated polymer. It is contemplated that other brominated polymers suitable for use in the flame retardant composition may have a bromine content of equal to or less than about 70 percent of the total weight of the brominated polymer.

It has been traditionally accepted that the flame retardant composition should be added to the foamable polymer mixture at a loading of about 1-5 wt%. If the flame retardant composition is HBCD, which has a bromine content of about 75 weight percent, then a loading of 1 to 5 weight percent will result in a foamable polymer mixture having a theoretical bromine content of about 0.75 to 3.75 weight percent. Since the bromine content of brominated polymers is lower than HBCD, it is generally expected that these brominated polymers require even higher loadings in the foamable polymer mixture. However, the present inventors have unexpectedly discovered that polymer foams can be loaded with flame retardant compositions comprising brominated polymers at surprisingly lower levels while still maintaining acceptable flame retardant characteristics. This unexpected finding resulted in polymer foams having much lower bromine content. The resulting low-bromine polymer foam has been found to meet the acceptance criteria of standard tests, such as the NFPA286 indoor corner test, the UL 723 surface burn performance test, the ASTM D2863 Limited oxygen index test, and the ASTM E84 surface burn performance test.

In certain exemplary embodiments, the flame retardant composition comprising the brominated polymer is added to the foamable polymer mixture in an amount of about 0.05 to 1.0 wt% brominated polymer, based on the total weight of the foamable polymer mixture (excluding the weight of the blowing agent composition). In certain exemplary embodiments, the flame retardant composition comprising the brominated polymer is added to the foamable polymer in an amount of about 0.1 to 0.95 wt%, including about 0.15 to 0.9 wt%, including about 0.2 to 0.85 wt%, including about 0.25 to 0.8 wt%, including about 0.3 to 0.75 wt%, including about 0.35 to 0.7 wt%, including about 0.4 to 0.65 wt%, including about 0.45 to 0.6 wt%, including about 0.5 to 0.55 wt%, including about 0.15 wt%, including about 0.2 wt%, including about 0.25 wt%, including about 0.3 wt%, including about 0.35 wt%, including about 0.4 wt%, including about 0.45 wt%, including about 0.5 wt%, including about 0.55 wt%, including about 0.60 wt%, including about 0.65 wt%, including about 0.7 wt%, including about 0.75 wt%, including about 0.8 wt%, including about 0.85 wt%, including about 0.95 wt% of the brominated polymer, based on the total weight of the foamable polymer mixture (in addition to the weight of the blowing agent composition). Assuming a bromine content of about 64 wt% of the total weight of the brominated polymer, in certain exemplary embodiments, the theoretical bromine content of the foamable polymer mixture is about 0.03 to 0.64 wt% based on the total weight of the foamable polymer mixture (excluding the weight of the blowing agent composition). In certain exemplary embodiments, the theoretical bromine content of the foamable polymer mixture is about 0.05 to 0.61 wt%, including about 0.1 to 0.58 wt%, including about 0.15 to 0.54 wt%, including about 0.18 to 0.51 wt%, including about 0.22 to 0.48 wt%, including about 0.26 to 0.45 wt%, including about 0.29 to 0.42 wt%, including about 0.32 to 0.38 wt%, including about 0.1 wt%, including about 0.13 wt%, including about 0.16 wt%, including about 0.19 wt%, including about 0.22 wt%, including about 0.25 wt%, including about 0.26 wt%, including about 0.29 wt%, including about 0.32 wt%, including about 0.35 wt%, including about 0.37 wt%, including about 0.4 wt%, including about 0.43 wt%, including about 0.45 wt%, including about 0.5 wt%, including about 0.55 wt%, including about 0.6 wt%, including about 0.64 wt%, based on the total weight of the foamable polymer mixture.

In some embodiments, the brominated polymer comprises a brominated polyolefin polymer. In some embodiments, the brominated polymer includes brominated polyethylene, brominated polypropylene, brominated polybutylene, brominated polybutadiene, and copolymers thereof. In some embodiments, the brominated polymer comprises a brominated block copolymer. In some embodiments, the brominated polymer comprises a block copolymer of polystyrene and brominated polybutadiene. In some embodiments, the brominated polymer comprises a high molecular weight block copolymer of polystyrene and brominated polybutadiene. Suitable brominated polymers include, but are not limited to, Emerald Innovation 3000(Chemtura Corporation, Philadelphia, PA, US), FR-122P (ICL Industrial Products, St. Louis, MO, US), or GreenCrest Flame Retardant (Albemarle Corporation, BatonRouge, LA, US).

Stabilizer for flame retardant composition

The flame retardant composition of the present invention may further comprise one or more stabilizers. Maintaining the stability of flame retardant compositions comprising brominated polymers is important when the brominated polymers are exposed to heat, shear rates, contaminants (e.g., zinc or other metals), and other processing conditions.

For example, when the manufacturing process includes a high temperature processing step, it is important to maintain the thermal stability of the flame retardant composition comprising the brominated polymer. Foamable polymer mixtures comprising brominated polymers may be exposed to elevated temperatures during melt blending and/or extrusion. Additionally, if the brominated polymer in the flame retardant composition is pre-mixed into a masterbatch prior to addition to the foamable polymer mixture, the pre-mixing step can expose the brominated polymer to additional high temperature processing. The use of recycled materials in the preparation of polymeric foams also causes stability problems because the recycled materials are repeatedly exposed to high temperatures (and possible contaminants) during the initial preparation as well as during recycling. The presence of zinc or other metals from the recycled material can have a catalytic effect that increases the degradation of the brominated flame retardant and decreases the thermal stability of the brominated flame retardant.

When the brominated polymer is exposed to high temperatures, the brominated polymer may undergo some degree of chemical decomposition. This decomposition may lead to loss of bromine and release of hydrobromic acid (HBr). Loss of bromine during the manufacturing process can negatively impact the flame retardant properties of the polymer foam. Loss of bromine also discolors the polymer foam, and in some embodiments, the discoloration may be severe. Chemical decomposition of the brominated polymer can also lead to the release of HBr, which can lead to corrosion and damage to processing equipment.

In certain exemplary embodiments, the flame retardant composition comprising the brominated polymer further comprises at least one stabilizer. For the purposes of the present invention, the term "stabilizer" includes, but is not limited to, antioxidants, heat stabilizers, UV stabilizers, acid scavengers, and other stabilizers suitable for maintaining the physical and chemical stability of the flame retardant composition (during its preparation, storage, and use) and the polymer foam into which the flame retardant composition is incorporated. In certain exemplary embodiments, the flame retardant composition may comprise a mixture of stabilizers. These stabilizers can act independently, additively, or synergistically to protect and stabilize flame retardant compositions comprising brominated polymers and polymer foams incorporating the flame retardant compositions.

In some exemplary embodiments, the flame retardant composition may include a stabilizer that is an antioxidant. Many types of antioxidants are known to those skilled in the art. One common class of antioxidants is hindered phenolic antioxidants. Examples of hindered phenolic antioxidants includeSeries of antioxidants (BASF, Florham Park, NJ, US) andserial antioxidants (Addivant, Danbury, CT, US). Another common class of antioxidants is organophosphite antioxidants. Examples of organophosphite antioxidants includeSeries of antioxidants (BASF, Florham Park, NJ, US) andserial antioxidants (Addivant, Danbury, CT, US). Another common class of antioxidants is aromatic amine antioxidants. Examples of aromatic amine antioxidants includeSeries of antioxidants (Addivant, Danbury, CT, US) anda series of antioxidants (Vanderbilt Chemicals, LLC, Norwalk, CT, US).

In some exemplary embodiments, the flame retardant composition may include a stabilizer that acts as an acid scavenger. One common type of acid scavenger is an epoxy compound, including but not limited to epoxy resins. These epoxy compounds may be based on bisphenol compounds, such as diglycidyl ether of bisphenol a. The epoxy compound may be an epoxy novolac resin or an epoxy cresol novolac resin. The epoxy compound may be brominated. Examples of useful epoxy compounds include F-2200HM, F-2001HM, and F-3014(ICL Industrial Products, St. Louis, MO, US), EPON 164 and EPON 165(Hexion, Inc., Columbus, OH, US) andECN series epoxy cresol novolak resins (Huntsman advanced materials, LLC, The Woodlands, TX, US).

Exemplary synergists include 2, 3-dimethyl-2, 3-diphenylbutane, poly (1, 4-diisopropylbenzene), bis (α -phenylethyl) sulfone, 2,2' -dimethyl-2, 2' -azobutane, 2,2' -dichloro-2, 2' -azobutane, 2,2' -dibromo-2, 2' -azobutane, α ' -bis-tert-butylperoxy-diisopropylbenzene, dioctyltin maleate, and dibutyltin maleate.

In certain exemplary embodiments, the carrier resin is selected from the group consisting of polystyrene, styrene-butadiene-styrene (SBS) copolymers and block copolymers, Styrene Acrylonitrile (SAN) copolymers, poly (α -methylstyrene), polychlorostyrene, polybromostyrene, polyethylene, polypropylene, and combinations thereof.

In certain exemplary embodiments, the flame retardant masterbatch may comprise a brominated polymer, an antioxidant, and a carrier resin. In certain exemplary embodiments, the flame retardant masterbatch may comprise a brominated polymer, an antioxidant, an epoxy compound, and a carrier resin. In certain exemplary embodiments, the flame retardant masterbatch may comprise a brominated polymer, an antioxidant, an epoxy compound, a synergist, and a carrier resin. In certain exemplary embodiments, the flame retardant masterbatch may comprise a brominated polymer, one or more antioxidants, an epoxy compound, a synergist, and a carrier resin. In certain exemplary embodiments, the brominated polymer may be about 10 to 60 weight percent of the flame retardant masterbatch, including about 20 to 55 weight percent of the total weight of the flame retardant masterbatch, including about 25 to 50 weight percent, including about 30 to 45 weight percent, including about 40 weight percent, including about 45 weight percent, including about 50 weight percent, and including about 55 weight percent. In certain exemplary embodiments, the additives (i.e., antioxidants, epoxy compounds, and/or synergists) may be about 0.5 to 20 weight percent of the flame retardant masterbatch, including about 1 to 18 weight percent, including about 1 to 15 weight percent, including about 2 to 13 weight percent, including about 3 to 12 weight percent, including about 5 to 11 weight percent, including about 7 to 10 weight percent, including about 5 weight percent, including about 7 weight percent, including about 8 weight percent, including about 9 weight percent, including about 9.5 weight percent, including about 10 weight percent, including about 10.5 weight percent, including about 11 weight percent, including about 11.5 weight percent, including about 12 weight percent, including about 13 weight percent, including about 14 weight percent, and including about 15 weight percent of the total weight of the flame retardant masterbatch.

Additional polymeric foam additives

In certain exemplary embodiments, the polymeric foam comprises at least one stabilizer including, but not limited to, antioxidants, thermal stabilizers, UV stabilizers, acid scavengers, and other stabilizers suitable for maintaining the physical and chemical stability of the polymeric foam incorporating the flame retardant composition. In certain exemplary embodiments, the polymeric foam may comprise a mixture of stabilizers. In certain exemplary embodiments, the at least one stabilizer in the polymeric foam may be a stabilizer other than the stabilizer in the flame retardant composition. In certain exemplary embodiments, the at least one stabilizer in the polymer foam is the same as the stabilizer in the flame retardant composition. In certain exemplary embodiments, the at least one stabilizer in the polymeric foam is different from the stabilizer in the flame retardant composition.

In certain exemplary embodiments, the polymeric foam comprises at least one synergist. The synergist can be added to a polymer foam containing a flame retardant composition comprising a brominated polymer. The synergist can help initiate decomposition of the brominated polymer, thereby improving the flame retardant properties of the brominated polymer. In certain exemplary embodiments, the at least one synergist in the polymer foam may be a synergist other than the synergist in the flame retardant composition. In certain exemplary embodiments, the at least one synergist in the polymer foam is the same as the synergist in the flame retardant composition. In certain exemplary embodiments, at least one synergist in the polymer foam is different from the synergist in the flame retardant composition.

The polymeric foam may optionally include additional additives such as nucleating agents, plasticizers, pigments, elastomers, processing aids, extrusion aids, fillers, antistatic agents, biocides, termiticides, colorants, oils, or waxes may be incorporated into the polymeric foam. These optional additives may be present in amounts necessary to achieve the desired properties of the foamable polymer mixture or resulting polymeric foam. The additives may be added to the foamable polymer mixture or they may be added before, during or after the polymerization process used to prepare the matrix polymer.

Foaming agent

Exemplary embodiments of the present invention use a blowing agent composition. Any blowing agent may be used according to the present invention. According to one aspect of the invention, the blowing agent or co-blowing agent is selected based on considerations of low global warming potential, low thermal conductivity, non-flammability, high solubility in the matrix polymer, high blowing ability, low cost, and overall safety of the blowing agent composition.

Non-halogenated blowing agents or co-blowing agents are desirable due to environmental concerns with halogenated hydrocarbons, including halogenated blowing agents. In some exemplary embodiments, the blowing agent or co-blowing agent comprises carbon dioxide. In some exemplary embodiments, carbon dioxide may be the only blowing agent. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and one or more co-blowing agents to achieve desired polymer foam properties in the final product. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and water. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and a hydrocarbon, such as pentane. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and methanol. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and ethanol. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and methyl formate. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and a halogenated blowing agent. However, in other exemplary embodiments, blowing agent compositions that do not include carbon dioxide may be used.

In some exemplary embodiments, the blowing agent or co-blowing agent in the foaming composition may include hydrocarbon gases and liquids. In some exemplary embodiments, the blowing agent or co-blowing agent in the foaming composition may include a liquid, such as alkyl esters (e.g., methyl formate), water, alcohols (e.g., ethanol), acetone, and mixtures thereof.

Hydrocarbon blowing or co-blowing agents may include, for example, propane, butane, pentane, hexane, and heptane. In some exemplary embodiments, the hydrocarbon blowing or co-blowing agent comprises butane, pentane, heptane, and combinations thereof. Butane blowing agents include, for example, n-butane and isobutane. Pentane blowing agents include, for example, n-pentane, isopentane, neopentane, and cyclopentane. Heptane blowing agents include, for example, n-heptane, isoheptane, 3-methylhexane, 2-dimethylpentane, 2, 3-dimethylpentane, 2, 4-dimethylpentane, 3-dimethylpentane, 3-ethylpentane, and 2,2, 3-trimethylbutane.

In some exemplary embodiments, the blowing agent or co-blowing agent in the blowing agent composition may include one or more halogenated blowing agents, such as Hydrofluorocarbons (HFCs), hydrochlorofluorocarbons, hydrofluoroethers, Hydrofluoroolefins (HFOs), Hydrochlorofluoroolefins (HCFO), hydrobromofluoroolefins, hydrofluoroketones, hydrochloroolefins, and fluoroiodocarbons.

Hydrofluoroolefin blowing or co-blowing agents may include, for example, 3,3, 3-trifluoropropene (HFO-1243zf), 2,3, 3-trifluoropropene, (cis and/or trans) -1,3,3, 3-tetrafluoropropene (HFO-1234ze), particularly the trans isomer, 1,1,3, 3-tetrafluoropropene, 2,3, 3-tetrafluoropropene (HFO-1234yf), (cis and/or trans) -1,2,3,3, 3-pentafluoropropene (HFO-1225ye), 1,1,3,3, 3-pentafluoropropene (HFO-1225zc), 1,1,2,3, 3-pentafluoropropene (HFO-1225yc), hexafluoropropene (HFO-1216), 2-fluoropropene, 1, 1-difluoropropene, 3, 3-difluoropropene, 4,4, 4-trifluoro-1-butene, 2,4,4, 4-tetrafluorobutene-1, 3,4,4, 4-tetrafluoro-1-butene, octafluoro-2-pentene (HFO-1438), 1,1,3,3, 3-pentafluoro-2-methyl-1-propene, octafluoro-1-butene, 2,3,3,4,4, 4-hexafluoro-1-butene, 1,1,1,4,4, 4-hexafluoro-2-butene (HFO-1336m/z), 1, 2-difluoroethylene (HFO-1132), 1,1,1,2,4,4, 4-heptafluoro-2-butene, 3-fluoropropene, 2, 3-difluoropropene, 1,1, 3-trifluoropropene, 1,3, 3-trifluoropropene, 1,1, 2-trifluoropropene, 1-fluorobutene, 2-fluoro-2-butene, 1, 1-difluoro-1-butene, 3, 3-difluoro-1-butene, 3,4, 4-trifluoro-1-butene, 2,3, 3-trifluoro-1-butene, 1,1,3, 3-tetrafluoro-1-butene, 1,4,4, 4-tetrafluoro-1-butene, 3,3,4, 4-tetrafluoro-1-butene, 4, 4-difluoro-1-butene, 1,1, 1-trifluoro-2-butene, 2,4,4, 4-tetrafluoro-1-butene, 1,1,1, 2-tetrafluoro-2-butene, 1,1,4,4, 4-pentafluoro-1-butene, 2,3,3,4, 4-pentafluoro-1-butene, 1,2,3,3,4,4, 4-heptafluoro-1-butene, 1,1,2,3,4,4, 4-heptafluoro-1-butene, and 1,3,3, 3-tetrafluoro-2- (trifluoromethyl) -propene. In some exemplary embodiments, the blowing or co-blowing agent comprises HFO-1234 ze.

The blowing or co-blowing agent may also include one or more Hydrochlorofluoroolefins (HCFOs), Hydrochlorofluorocarbons (HCFCs) or Hydrofluorocarbons (HFCs), such as HCFO-1233, 1-chloro-1, 2,2, 2-tetrafluoroethane (HCFC-124), 1, 1-dichloro-1-fluoroethane (HCFC-141b), 1,1,1, 2-tetrafluoroethane (HFC-134a), 1,1,2, 2-tetrafluoroethane (HFC-134), 1-chloro-1, 1-difluoroethane (HCFC-142b), 1,1,1,3, 3-pentafluorobutane (HFC-365mfc), 1,1,1,2,3,3, 3-heptafluoropropane (HFC-227ea), trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and dichlorofluoromethane (HCFC-22).

The term "HCFO-1233" is used herein to refer to all chlorotrifluoropropenes.

Included among the chlorotrifluoropropenes are cis-and trans-1, 1, 1-trifluoro-3-chloropropene (HCFO-1233zd or 1233 zd). The term "HCFO-1233 zd" or "1233 zd" is used generically herein to refer to 1,1, 1-trifluoro-3-chloro-propene, whether it is cis or trans. The terms "cis HCFO-1233 zd" and "trans HCFO-1233 zd" are used herein to describe the cis and trans forms of 1,1, 1-trifluoro-3-chloropropene, respectively. Thus, the term "HCFO-1233 zd" includes within its scope cis HCFO-1233zd (also referred to as 1233zd (Z)), trans HCFO-1233zd (also referred to as 1233(E)), and all combinations and mixtures thereof.

In some exemplary embodiments, the blowing or co-blowing agent may include one or more hydrofluorocarbons. The specific hydrofluorocarbon used is not particularly limited. A non-exhaustive list of examples of suitable HFC blowing or co-blowing agents include 1, 1-difluoroethane (HFC-152a), 1,1,1, 2-tetrafluoroethane (HFC-134a), 1,1,2, 2-tetrafluoroethane (HFC-134), 1,1, 1-trifluoroethane (HFC-143a), difluoromethane (HFC-32), 1,3,3, 3-pentafluoropropane (HFO-1234ze), pentafluoroethane (HFC-125), fluoroethane (HFC-161), 1,1,2,2,3, 3-hexafluoropropane (HFC 236ca), 1,1,1,2,3, 3-hexafluoropropane (HFC-236ea), 1,1,1,3,3, 3-hexafluoropropane (HFC-236fa), 1,1,1,2,2, 3-hexafluoropropane (HFC-245ca), 1,1,2,3, 3-pentafluoropropane (HFC-245ea), 1,1,1,2, 3-pentafluoropropane (HFC-245eb), 1,1,1,3, 3-pentafluoropropane (HFC-245fa), 1,1,1,4,4, 4-hexafluorobutane (HFC-356mff), 1,1,1,3, 3-pentafluorobutane (HFC-365mfc), and combinations thereof.

In some exemplary embodiments, the blowing or co-blowing agent is selected from hydrofluoroolefins, hydrofluorocarbons, and mixtures thereof. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and a co-blowing agent HFC-134 a. In some exemplary embodiments, the blowing agent composition comprises carbon dioxide and HFO-1234 ze. The co-blowing agents specified in the present invention may be used alone or in combination.

In some exemplary embodiments, the total blowing agent composition is present in an amount of from about 1 to 15 weight percent, and in exemplary embodiments, from about 2 to 10 weight percent, or from about 3 to 9 weight percent (based on the total weight of all ingredients except the blowing agent composition).

In some exemplary embodiments, the blowing agent composition may be introduced in liquid or gaseous form (e.g., a physical blowing agent). In some exemplary embodiments, the blowing agent composition may be generated in situ while generating the foam (e.g., a chemical blowing agent). In some exemplary embodiments, the blowing agent may be formed by decomposing another component during the preparation of the foamed thermoplastic. For example, carbonate components, polycarbonate, sodium bicarbonate or azodicarbonamide and decompose and/or degrade upon heating to form CO₂、N₂And H₂Other components of O may be added to the foaming resin and generate foaming gas (e.g., CO) when heated during extrusion₂Or N₂)。

Preparation method

In some embodiments, the polymer foam of the present invention is an extruded polymer foam prepared by an extrusion process. The extrusion apparatus may comprise a single or twin screw extruder comprising a barrel surrounding a screw on which is provided a helical flight configured to compress and heat material introduced into the screw extruder. The other components of the base polymer and foamable polymer mixture may be fed into the screw extruder from one or more feed hoppers as flowable solids (e.g., beads, granules or pellets) or as liquid or semi-liquid melts. The flame retardant composition and optionally one or more other additives may be fed into the screw extruder with the base polymer, or these additives may be added through a separate port configured to inject the additives through a barrel into the polymer mixture in the screw extruder. As the polymer mixture advances through the screw extruder, the reduced flight pitch defines a decreasing space through which the polymer mixture is forced by the rotation of the screw. This reduced volume is used to increase the pressure of the polymer mixture to obtain a polymer melt (if a solid feedstock is used) or to increase the pressure of the polymer melt. One or more additional ports may be provided through the cylinder for injecting one or more blowing agents into the molten polymer mixture. In some exemplary embodiments, the resulting molten polymer mixture is additionally blended such that each additive is generally uniformly distributed in the molten polymer mixture to obtain a foamable polymer mixture.

The foamable polymer mixture is then forced through an extrusion die and out of the die into a reduced pressure zone (which may be subatmospheric), thereby expanding the blowing agent and producing a polymer foam. The reduced pressure may be obtained gradually as the foamable polymer mixture advances through incremental openings provided in the die or through some suitable device disposed downstream of the extrusion die to control to some extent the manner in which the pressure applied to the foamable polymer mixture is reduced. Once the polymer foam is formed, the polymer foam may be subjected to additional processing, such as calendering, water immersion, cooling spray or other operations, to control the thickness and other properties of the resulting polymer foam product.

In some embodiments, the polymer foam of the present invention is an extruded polymer bead prepared by a bead extrusion process. Bead extrusion is similar to the extrusion process previously described. However, the extrusion die contains a plurality of small orifices such that the foamable polymer mixture is extruded as beads. The beads typically have a diameter in the range of about 0.05 to 2.0 mm. Furthermore, once the beads exit the extrusion die, the foamable polymer mixture is not allowed to foam. Instead, the beads containing the foamable polymer mixture are discharged into a coolant chamber or bath and the beads are rapidly cooled to below the glass transition temperature (Tg) of the foamable polymer mixture. This rapid cooling prevents the foamable polymer mixture in the beads from foaming. The beads may be later expanded by conventional methods, such as heating methods.

In some exemplary embodiments of bead extrusion, the base polymer, flame retardant composition, blowing agent, and optional additives are introduced into an extruder as described above to form a foamable polymer mixture. In some exemplary embodiments of bead extrusion, the base polymer, flame retardant composition, and optional additives are introduced into the extruder as described above to form a polymer mixture, but the blowing agent is added to the extruded beads through the pressure vessel after the beads are extruded and cooled.

In some embodiments, the polymer foam of the present invention is an expanded polymer foam prepared by an emulsion or suspension polymerization process. In an exemplary embodiment of the expanded polymeric foam, the matrix polymer is polymerized from monomers dispersed in a liquid phase within the reaction vessel. The flame retardant composition and other optional additives are also added to the liquid phase within the reaction vessel. In some embodiments, the monomers of the base polymer, the flame retardant composition, and other optional additives are dispersed in the liquid phase within the reaction vessel at about the same time. In some embodiments, the monomers of the base polymer are dispersed in the liquid phase within the reaction vessel and the polymerization reaction to form the base polymer occurs before the flame retardant composition and other optional additives are dispersed in the liquid phase within the reaction vessel. In some embodiments, one or more blowing agents are added to the polymer mixture by adding the blowing agent as a diluent to the liquid phase within the reaction vessel during the polymerization reaction. In some embodiments, one or more blowing agents are used as the liquid phase within the reaction vessel during the polymerization reaction. In some embodiments, one or more blowing agents are added to the polymer mixture in the pressure vessel after the polymerization reaction is complete.

Polymer foam

The preparation process produces a polymer foam. In some exemplary embodiments, the process of preparing the foamable polymer mixture produces a rigid, substantially closed cell polymeric foam sheet prepared by an extrusion process. The extruded foam has a cell structure with a cell membrane and struts defining cells. Struts are formed at the intersections of the cellular membranes covering the interconnected cellular windows between the struts. In some exemplary embodiments, the foam has an average density of less than 10 pounds per cubic foot (pcf), or less than 5pcf, or less than 3 pcf. In some exemplary embodiments, the polymer foam has a density of about 1 to 4.5 pcf. In some exemplary embodiments, the polymer foam has a density of about 1.2 to 4 pcf. In some exemplary embodiments, the polymer foam has a density of about 1.3 to 3.5 pcf. In some exemplary embodiments, the polymer foam has a density of about 1.4 to 3 pcf. In some exemplary embodiments, the polymer foam has a density of about 1.5 to 2.5 pcf. In some exemplary embodiments, the polymer foam has a density of about 1.75 to 2.25 pcf. In some exemplary embodiments, the polymer foam has a density of about 1.5pcf, or less than 1.5 pcf.

It is to be understood that the phrase "substantially closed cells" means that the foam contains all closed cells or that almost all of the cells in the cell structure are closed. In most exemplary embodiments, no more than 30% of the cells are open cells, particularly, no more than 10%, or no more than 5% are open cells, or "non-closed" cells as determined by standard test methods (e.g., ASTM D6226, "standard test method for open cell content of rigid cell plastics"). In some exemplary embodiments, about 1.10 to 2.85% of the cells are open cells. The closed cell structure helps to increase the R-value of the formed foamed insulation product. It is understood, however, that it is within the scope of the present invention to create an open cell structure.

In addition, the foamable polymer mixtures of the present invention produce extruded foams having an insulation value per inch (R value) of at least 4, or about 4 to 7, as determined by standard test methods such as ASTM C518. Further, the average cell size of the foamable polymer mixtures and polymer foams of the present invention may range from about 0.05 to 0.4mm (50 to 400 microns), in some exemplary embodiments from 0.1 to 0.3mm (100 to 300 microns), and in some exemplary embodiments from 0.11 to 0.25mm (110 to 250 microns). The polymer foam may be formed into insulation products such as rigid insulation panels, insulating foams, packaging products, and building or underground insulation (e.g., highway, airport runway, railway, and underground utility insulation).

The foamable polymer mixtures of the present invention may additionally produce polymer foams having high compressive strength as determined by standard test methods (e.g., ASTM D1621). The compressive strength defines the ability of the foam to withstand axial thrust. In some exemplary embodiments, the polymer foam has a compressive strength of about 6 to 120 psi. In some exemplary embodiments, the foamable polymer mixture of the present invention produces a polymer foam having a compressive strength of about 10-110 psi.

In some exemplary embodiments, the polymer foams of the present invention have a high level of dimensional stability as determined by standard test methods (e.g., ASTM D2126). In some exemplary embodiments, the dimensional change in any direction is 5% or less. Furthermore, the cells of the foam formed from the foamable polymer mixture of the present invention are desirably unimodal, with a relatively uniform average cell size. As used herein, the average cell size is the average of the cell sizes measured in the X, Y and Z directions. For extruded foams, the "X" direction is the extrusion direction, the "Y" direction is the transverse direction, and the "Z" direction is the thickness. In the present invention, the greatest effect of cell enlargement is in the X and Y directions, which is desirable from the standpoint of orientation and R value. Further process improvements would allow for increased Z-orientation to improve mechanical properties while still achieving acceptable thermal properties. The polymer foams of the present invention are useful in the preparation of insulation products such as rigid insulation boards, insulation foams and packaging products.

Examples

The inventive concept has been described above generally and by way of various exemplary embodiments. While the general inventive concept has been set forth in what is believed to be exemplary illustrative embodiments, various alternatives known to those skilled in the art may be selected from the foregoing disclosure. In addition, the following examples are intended to better illustrate the invention, but in no way limit the general inventive concept of the present invention.

Example 1

A polymeric flame retardant masterbatch (PFRM-1) containing Emerald 3000 brominated polymer (Chemtura Corporation, philiadelphia, PA, US) was prepared. PFRM-1 comprises about 40 wt% Emerald 3000 brominated polymer, and about 60 wt% polystyrene containing additives (e.g., stabilizers and synergists). The bromine content of Emerald 3000 was about 64 wt%.

Example 2

A sample of extruded polystyrene ("XPS") foam of the present invention (sample a) was prepared using a twin screw extruder. Polystyrene was melted in an extruder and a sufficient amount of PFRM-1 masterbatch was added to provide a brominated polymer content of 1.0 wt% in the expanded polystyrene mixture. Since the bromine content of the brominated polymer was about 64 weight percent, the theoretical bromine content of the expanded polystyrene mixture of sample A was about 0.6 weight percent. A blowing agent is injected into the polystyrene mixture to form a foamable polymer mixture. The foamable polymer mixture was then cooled to the desired foaming conditions and extruded to form XPS foam boards having a thickness of 1.5 inches.

A comparative control sample of XPS foam (control 1) was prepared as described above, except that HBCD flame retardant was used instead of PFRM-1 masterbatch. Sufficient HBCD flame retardant was added to provide a HBCD content of 0.8 wt% in the expandable polystyrene blend. Since the bromine content of HBCD is about 75 wt%, the theoretical bromine content of the expandable polystyrene mixture of control 1 is about 0.6 wt%.

XPS foam sample a and control 1 were evaluated using test method NFPA286, "standard method of fire test for evaluating the contribution of wall and ceiling decoration to indoor fire growth. The peak heat release rate (peak HRR) and total smoke generated during the test were determined. The samples were also evaluated using test method ASTM D2863, "standard test method for measuring the minimum oxygen concentration for candle-like burning of support plastics (oxygen index)". The test results of example 2 are shown in table 1.

TABLE 1

Flame retardant used in sample a was Emerald 3000 brominated polymer.

The flame retardant used in # control 1 was HBCD.

Acceptance criteria for NFPA286 (annex C, 2015 edition) stipulate that peak HRR should not exceed 800kW and total smoke should not exceed 1000m during the test². The test results in Table 1 show that sample A, which contains 1 wt% brominated polymer as a flame retardant, has results comparable to the control 1 sample, which contains 0.8 wt% HBCD. Sample a and control 1 both had a theoretical bromine content of about 0.6 wt%. Both sample a and control 1 passed the acceptance criteria of the NFPA286 test. The ASTM D2863 oxygen index values of the two samples were comparable and met the minimum oxygen index value of 24% of ASTM C578 "Standard Specification for rigid foam polystyrene insulation".

Example 3

Four XPS foam samples were prepared using a twin screw extruder. The polystyrene was melted in the extruder and different amounts of the PFRM-1 masterbatch were added to the extruder. A blowing agent is injected into each expandable polystyrene mixture to form a foamable polymer mixture. The foamable polymer mixture was then cooled to the desired foaming conditions and extruded to form XPS foam boards having a thickness of 2.0 inches.

The XPS foam samples were analyzed for actual bromine content by X-ray fluorescence spectroscopy (XRF). For this test, each foam sample was melted in an XRF sample cup at 260 ℃ for 8 minutes and then analyzed for bromine content. One foam sample (C) had portions analyzed from different areas of the foam sample to confirm the uniformity of bromine content in the XPS foam. The results are shown in Table 2.

TABLE 2

Sample ID	Additive masterbatch (wt%)	Added Emerald 3000 (wt%)	Actual bromine content (wt%)
				B	1.0	0.40	0.15
C	0.7	0.28	0.10
				D	0.5	0.20	0.07

Example 4

The four XPS samples from example 3 were evaluated using the test method NFPA286, "standard method of fire test for evaluating the contribution of wall and ceiling interior decoration to indoor fire growth". The peak heat release rate (peak HRR) and total smoke generated during the test were determined. The samples were also evaluated using test method ASTM D2863, "standard test method for measuring the minimum oxygen concentration for candle-like burning of support plastics (oxygen index)". The test results of example 4 are shown in table 3.

TABLE 3

Acceptance criteria for NFPA286 (annex C, 2015 edition) stipulate that peak HRR should not exceed 800kW and total smoke should not exceed 1000m during the test². The test results in Table 3 show that samples B, C and D, which contained 0.2 to 0.4 wt% brominated polymer as a flame retardant, passed the acceptance criteria for the NFPA286 test. All three samples had comparable ASTM D2863 oxygen index values and met the minimum oxygen index value of 24% of ASTM C578 "Standard Specification for rigid foam polystyrene insulation".

Example 5

A second polymeric flame retardant masterbatch (PFRM-2) was prepared as described in example 1 above. PFRM-2 comprises about 40 wt% Emerald 3000 brominated polymer and about 60 wt% polystyrene containing additives (e.g., stabilizers) but no synergist. The bromine content of Emerald 3000 was about 64 wt%.

Four XPS foam samples were prepared using a twin screw extruder. For both samples, the polystyrene was melted in the extruder and different amounts of PFRM-1 masterbatch with synergist (from example 1) were added to the extruder. For the other two samples, the polystyrene was melted in the extruder and different amounts of the PFRM-2 masterbatch without synergist (from example 5) were added to the extruder. A blowing agent is injected into each expandable polystyrene mixture to form a foamable polymer mixture. The foamable polymer mixture was then cooled to the desired foaming conditions and extruded to form XPS foam boards having a thickness of 1.0 inch.

The four XPS samples from example 5 were evaluated using the test method NFPA286, "standard method of fire test for evaluating the contribution of wall and ceiling interior decoration to indoor fire growth". The peak heat release rate (peak HRR) and total smoke generated during the test were determined. The samples were also evaluated using test method ASTM D2863, "standard test method for measuring the minimum oxygen concentration for candle-like burning of support plastics (oxygen index)". The test results of example 5 are shown in table 4.

TABLE 4

Acceptance criteria for NFPA286 (annex C, 2015 edition) stipulate that peak HRR should not exceed 800kW and total smoke should not exceed 1000m during the test². The test results in Table 4 show that samples F, G, H and I, which contain 0.25 to 0.50 weight percent brominated polymer as a flame retardant, pass the acceptance criteria of the NFPA286 test. The NFPA286 test results were comparable for samples with and without synergist in the composition. All four samples also had comparable ASTM D2863 oxygen index values and met the minimum oxygen index value of 24% of ASTM C578 "Standard Specification for rigid foam polystyrene insulation".

As used in this specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. To the extent that the term "includes" or "including" is used in either the detailed description or the claims, it is intended to be inclusive in a manner similar to the term "comprising" as that term is interpreted when employed as a transitional word in a claim. Further, to the extent that the term "or" is used (e.g., a or B), it is intended to mean "a or B or both. When applicants mean "only a or B and not both," the term "only a or B and not both" will be used. Thus, the term "or" as used herein is inclusive, and not exclusive. Furthermore, to the extent that the term "in" or "in" is used in either the specification or the claims, it is intended to mean "on" or "over.

Unless otherwise stated in the present invention, all sub-embodiments and alternative embodiments are individual sub-embodiments and alternative embodiments of all embodiments described in the present invention. While the present application has been illustrated by the description of embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the application, in its broader aspects, is not limited to the specific details, the representative process, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's general disclosure.

Claims (44)

1. A foamable polymer mixture comprising:

a polymer composition;

a blowing agent composition; and

a flame retardant composition comprising a brominated polymer;

wherein the foamable polymer mixture contains about 0.01 to 0.5 wt% bromine.

2. The foamable polymeric mixture of claim 1, wherein the brominated polymer comprises a block copolymer of polystyrene and brominated polybutadiene.

3. The foamable polymeric mixture of claim 1, wherein the brominated polymer has a bromine content of less than about 70 wt%.

4. The foamable polymeric mixture of claim 1, wherein the flame retardant composition further comprises at least one stabilizer.

5. The foamable polymeric mixture of claim 4, wherein the at least one stabilizer is selected from the group consisting of phenolic antioxidants, organophosphite antioxidants, aromatic amine antioxidants, epoxy stabilizers, brominated epoxy stabilizers, and combinations thereof.

6. The foamable polymeric mixture of claim 1, wherein the flame retardant composition further comprises a synergist.

7. The foamable polymeric mixture of claim 6, wherein the synergist is selected from the group consisting of 2, 3-dimethyl-2, 3-diphenylbutane, poly (1, 4-diisopropylbenzene), bis (α -phenylethyl) sulfone, 2' -dimethyl-2, 2' -azobutane, 2' -dichloro-2, 2' -azobutane, 2' -dibromo-2, 2' -azobutane, α ' -bis-tert-butylperoxy-diisopropylbenzene, dioctyltin maleate, dibutyltin maleate, and combinations thereof.

8. The foamable polymeric mixture of claim 1, wherein the blowing agent is selected from the group consisting of water, carbon dioxide, methyl formate, hydrocarbons, hydrofluoroolefins, hydrofluorocarbons, and mixtures thereof.

9. The foamable polymeric mixture of claim 1, wherein the polymeric composition comprises polystyrene, polyethylene terephthalate (PET), Styrene Acrylonitrile (SAN) copolymer, or combinations thereof.

10. A polymer foam prepared from the foamable polymer mixture of claim 1.

11. A method of making an extruded polymeric foam comprising:

introducing the polymer composition into a screw extruder to form a polymer melt;

introducing a flame retardant composition comprising a brominated polymer into the polymer melt;

injecting a blowing agent composition into the polymer melt to form a foamable polymer material; and

extruding the foamable polymer material to form an extruded polymer foam,

wherein the extruded polymeric foam comprises about 0.01 to 0.5 wt% bromine.

12. The method of claim 11, wherein the brominated polymer comprises a block copolymer of polystyrene and brominated polybutadiene.

13. The method of claim 11, wherein the brominated polymer has a bromine content of less than about 70 wt%.

14. The method of claim 11, wherein the flame retardant composition further comprises at least one stabilizer.

15. The method of claim 14, wherein the at least one stabilizer is selected from the group consisting of phenolic antioxidants, organophosphite antioxidants, aromatic amine antioxidants, epoxy stabilizers, brominated epoxy stabilizers, and combinations thereof.

16. The method of claim 11, wherein the flame retardant composition further comprises a synergist.

17. The method of claim 16, wherein the synergist is selected from the group consisting of 2, 3-dimethyl-2, 3-diphenylbutane, poly (1, 4-diisopropylbenzene), bis (α -phenylethyl) sulfone, 2' -dimethyl-2, 2' -azobutane, 2' -dichloro-2, 2' -azobutane, 2' -dibromo-2, 2' -azobutane, α ' -bis-tert-butylperoxy-diisopropylbenzene, dioctyltin maleate, dibutyltin maleate, and combinations thereof.

18. The method of claim 11, wherein the blowing agent is selected from the group consisting of water, carbon dioxide, methyl formate, hydrocarbons, hydrofluoroolefins, hydrofluorocarbons, and mixtures thereof.

19. The method of claim 11, wherein the polymer composition comprises polystyrene, polyethylene terephthalate (PET), Styrene Acrylonitrile (SAN) copolymer, or a combination thereof.

20. An extruded polymeric foam comprising a foamable polymer material, wherein the foamable polymer material comprises:

a polymer composition;

a flame retardant composition comprising a brominated polymer; and

a blowing agent composition;

wherein the extruded polymeric foam comprises about 0.01 to 0.5 wt% bromine.

21. The extruded polymeric foam according to claim 20, wherein the polymer composition comprises polystyrene, polyethylene terephthalate (PET), Styrene Acrylonitrile (SAN) copolymer, or a combination thereof.

22. The extruded polymeric foam of claim 20, wherein the brominated polymer comprises a block copolymer of polystyrene and brominated polybutadiene.

23. The extruded polymer foam of claim 20, wherein the brominated polymer has a bromine content of less than about 70 wt%.

24. The extruded polymer foam of claim 20, wherein the flame retardant composition further comprises at least one stabilizer.

25. The extruded polymeric foam of claim 24, wherein the at least one stabilizer is selected from the group consisting of phenolic antioxidants, organophosphite antioxidants, aromatic amine antioxidants, epoxy stabilizers, brominated epoxy stabilizers, and combinations thereof.

26. The extruded polymer foam of claim 20, wherein the flame retardant composition further comprises a synergist.

27. The extruded polymeric foam of claim 26, wherein the synergist is selected from the group consisting of 2, 3-dimethyl-2, 3-diphenylbutane, poly (1, 4-diisopropylbenzene), bis (α -phenylethyl) sulfone, 2' -dimethyl-2, 2' -azobutane, 2' -dichloro-2, 2' -azobutane, 2' -dibromo-2, 2' -azobutane, α ' -bis-tert-butylperoxy-diisopropylbenzene, dioctyltin maleate, dibutyltin maleate, and combinations thereof.

28. The extruded polymeric foam of claim 20, wherein the blowing agent is selected from the group consisting of water, carbon dioxide, methyl formate, hydrocarbons, hydrofluoroolefins, hydrofluorocarbons, and mixtures thereof.

29. A method of making an expanded polymeric foam comprising:

introducing the monomer dispersed in the liquid phase into a reaction vessel;

introducing a flame retardant composition comprising a brominated polymer into the reaction vessel;

injecting a blowing agent composition into the reaction vessel;

polymerizing monomers in the reaction vessel to form a polymer; and

expanding the polymer to form an expanded polymer foam,

wherein the expanded polymeric foam comprises from about 0.01 to 0.5 weight percent bromine.

30. The method of claim 29, wherein the brominated polymer has a bromine content of less than about 70 wt%.

31. The method of claim 29, wherein the flame retardant composition further comprises at least one stabilizer.

32. The method of claim 29, wherein the flame retardant composition further comprises at least one synergist.

33. The method of claim 29, wherein the blowing agent is selected from the group consisting of water, carbon dioxide, methyl formate, hydrocarbons, hydrofluoroolefins, hydrofluorocarbons, and mixtures thereof.

34. The method of claim 29, wherein more than one monomer is introduced into the reaction vessel.

35. The method of claim 29, wherein the polymer comprises polystyrene, polyethylene terephthalate (PET), Styrene Acrylonitrile (SAN) copolymer, or a combination thereof.

36. An expanded polymeric foam comprising a foamable polymer material comprising:

a monomer dispersed in the liquid phase, wherein the monomer polymerizes into a polymer;

a flame retardant composition comprising a brominated polymer; and

a blowing agent composition;

wherein the expanded polymeric foam comprises from about 0.01 to 0.5 weight percent bromine.

37. The expanded polymer foam of claim 36, wherein the polymer composition comprises polystyrene, polyethylene terephthalate (PET), Styrene Acrylonitrile (SAN) copolymer, or a combination thereof.

38. The expanded polymeric foam of claim 36, wherein the brominated polymer comprises a block copolymer of polystyrene and brominated polybutadiene.

39. The expanded polymer foam of claim 36, wherein the brominated polymer has a bromine content of less than about 70 wt%.

40. The expanded polymer foam according to claim 36, wherein the flame retardant composition further comprises at least one stabilizer.

41. The expanded polymer foam according to claim 40, wherein the at least one stabilizer is selected from the group consisting of phenolic antioxidants, organophosphite antioxidants, aromatic amine antioxidants, epoxy stabilizers, brominated epoxy stabilizers, and combinations thereof.

42. The expanded polymer foam of claim 36, wherein the flame retardant composition further comprises a synergist.

43. The expanded polymer foam of claim 42, wherein the synergist is selected from the group consisting of 2, 3-dimethyl-2, 3-diphenylbutane, poly (1, 4-diisopropylbenzene), bis (α -phenylethyl) sulfone, 2' -dimethyl-2, 2' -azobutane, 2' -dichloro-2, 2' -azobutane, 2' -dibromo-2, 2' -azobutane, α ' -bis-tert-butylperoxy-diisopropylbenzene, dioctyltin maleate, dibutyltin maleate, and combinations thereof.

44. The expanded polymer foam of claim 36, wherein the blowing agent is selected from the group consisting of water, carbon dioxide, methyl formate, hydrocarbons, hydrofluoroolefins, hydrofluorocarbons, and mixtures thereof.