HK1114114B - An intumescent fire retardant and the method of its manufacture - Google Patents

Description

Intumescent flame retardant and method for producing same

Technical Field

The subject of the invention is an intumescent flame retardant and a process for its manufacture. The use of modifiers in the form of so-called "nanoparticles" in expansion systems improves the effective flame retardancy and the efficiency of the system in thermal insulation. The high degree of dispersion of the particles has an effect on the decomposition of the expansion system and on the combustion process. Therefore, the structure and heat resistance of the formed carbon layer are improved.

Background

The following intumescent flame retardants are known to exist: based on synthetic resins incorporating pore-forming, charring and dehydrating substances. These flame retardants are most often in the form of paints or coatings. Recent advances in the use and manufacture of nano-scale micro-particles have created new possibilities for flame retardant research.

The expansion system based on particles with large dispersion coefficients, so-called "nano-molecules", is a new concept. Recent research in the fabrication of very small particles (nano-scale) also opens new avenues for material production. Nowadays, nanotechnology plays a key role in several disciplines, such as material processing, precision mechanics, optics, electronics, or ceramics. Nanomaterial technology is being put to practical use at ever increasing speeds.

This is a new direction for fire protection, but most of the solutions involve flame retardant nanocomposites containing nanostructures.

We have not seen any reports (commercial or literature) on intumescent flame retardants using nanoscale materials. This is because the "made available flame retardant" compounds with nanomolecules are very difficult to obtain. Metal nanomolecules (gold, palladium, cobalt), nanomolecule polymers and other compounds (such as aluminum polyphosphate) and metal oxides (such as Fe)₂O₃) The aspects have had many successes and thus have been applied. Currently, most research appears to focus on the possibility of producing nanoscale compounds. Manufacture of nano-scale MgO, SiO₂And carbon black are well known in the art. However, the manufacture (research and application techniques) of agents and overall systems that effectively reduce the flammability of materials is still in its infancy.

IMB researchers have combined nanotechnology and chemistry to synthesize precisely controlled-size magnetic nanomolecules (ferro-platinum magnetic particles), which have one day allowed more than 100 times more information to be stored on hard disks or other data storage media than existing products.

Degussa-Huels is driving the development of new technologies for the manufacture of nanoparticles such as Aerosil (silica) and carbon black.

Publications relating to the synthesis, characterization and theoretical modeling of carbon nanotubes have reported that the electronic properties of these tubes are "extremely sensitive" to oxygen, so that contact with air can convert semiconducting nanotubes into metallic conductors.

Nanophase Technologies corp. has received a preliminary order for its NanoClad metal oxides, which are used for high application reliability thermal spray coatings on U.S. naval vessels.

Most fiber optic connector (connector) companies have received orders for polished films coated with diamond particles.

Thanks to the latest discovery by Michigan Molecular Institute (MMI) and Dendritech, Inc, new technologies for the manufacture and use of products from computer chips to medical diagnostic devices may soon become possible. This scientific breakthrough involves the use of a novel polymer dendrimer (dendrimer) to capture the metal bundle, thereby enabling the formation of a nanocomposite. Dendrimer-based materials exhibit novel molecular structures that mimic dendritic branching. The size, shape and surface reactivity can be controlled very precisely, and it is now possible to place metals inside dendrimers at the atomic and nano level. These can trap and contain substances that are generally considered insoluble, such as gold, silver, copper, nickel, cobalt, platinum and iron. In addition, inorganic salts, which are generally insoluble in water, such as silver halides, can now be dissolved.

Cloisite nanoclay, a high aspect ratio kaolin Clay-based additive for the plastics industry, has been developed by Southern Clay Products, a Laporte, Inc. In dry form, Cloisite is present in clusters or aggregates of kaolin platelets with little surface exposure. Nanoclay platelets are characterized by very high surface area and high aspect ratio. To maximize the potential surface area of the polymer dispersion, the kaolin platelets must be uniformly distributed throughout the polymer matrix with a spacing of at least 7 nanometers. Nanocomposite plastics have better dimensional stability at low reinforcement loading levels, higher heat distortion temperatures, and better recyclability than typical plastic composites. Flame retardancy is also improved compared to conventional reinforced parts, and electrostatic adhesion in films formed from nanocomposites is also reduced, as reported in: [ NANOPATICLE NEWS, Volume 3, Number 3, April 2000, Business Communications Co., Inc. Norwalk, Ct 06856; "Flame Retardancy", annular BCC Conference on Flame Retardancy, Recent Advances in Flame Retardaney of Polymeric Materials, Holiday InnSelect, Stamford, Connecticut ].

Patent specification PL 175344(1995-01-11) describes an intumescent flame retardant in the form of a transparent coating which forms an insulating foam layer at elevated temperatures. Characterized in that it comprises urea and/or melamine, dicyandiamide, formaldehyde, phosphoric acid or derivatives thereof and/or boric acid and/or ammonium sulphate, starch or dextrin, melamine-formaldehyde resins, glycols or glycerol. The manufacturing process is based on the condensation of melamine-formaldehyde resins, wherein a part of the components is added at a constant stirring speed at 70-90 ℃ and the rest of the components are added at room temperature. The material is used for decorative and transparent coatings for wood and wood-like materials.

Patent specification PL 161134(1988-12-08) describes a flame retardant and a method for its manufacture.

Patent specification PL 166657(1991-04-16) describes a flame-retardant putty consisting of a support and a hydrated sodium silicate-containing substance which increases in volume at elevated temperature, characterized in that the support is a granulated or ground foam polystyrene with a diameter of 0.5 to 20 mm, which contains 85 to 94% by volume. The particles are surrounded by 6-15% by volume of an intumescent mixture consisting of 65-85% sodium silicate hydrate, 2-35% silica, 0.5-5% dehydrating agent, 0.1-1.8% inorganic coloring pigment and 0.2-2% inorganic coating pigment.

Patent specification US3440201 describes an expanding agent for producing transparent coatings and a process for its production. The compound is obtained by reacting polyol phosphate with hydrocarbyloxy (alcoxy) melamine formaldehyde resin in an organic solvent.

Patent specification CN1540047 (published 2004-10-27) describes a nano-meterA flame retardant and a method for producing a flame-resistant fiber. The flame-retardant fire-resistant nanofiber is prepared by the following method: from SiO₂And Al₂O₃A nano additive is prepared, mixed with cellulose, and spinning dope (spinning dope) is prepared and spun. Its advantages are high strength and elongation, low moisture regain, and high refractory effect (1300 deg.C). Patent specification CN1544552 (published 2004-11-10) describes a fire-retardant channel paint based on nano-surface treatment technology and a preparation method thereof. The present invention relates to a fire-resistant channel paint comprising a fire-resistant paint and a nanopaint having surface-functional properties modified, wherein the fire-resistant paint comprises a silicate, a phosphate binder, a polymer emulsion, an aggregate, reinforcing fibers, and a combustion inhibitor, and the nanopaint has modified surface-functional properties comprising a non-combustible composite polymer-based material, a composite nanomaterial, a nanomaterial surface modifier, a flame retardant plasticizer, solvent gasoline, and a fluid deforming agent.

Patent specification CN1542036 (published 2004-11-03) describes a method for producing a nano magnesium hydroxide flame retardant. The invention relates to a method for preparing a nano magnesium hydroxide flame retardant, which is part of the physicochemical process for preparing the compound. The inventive method is characterized by the activity of the polymer protective agent, wherein soluble magnesium salts and soluble alkaline substances are converted into magnesium hydroxide powder by forced emulsification and precipitation in a high-shear homogenizing emulsifier, and subsequently filtered, washed and dried. The special high shear homogenizing emulsifier is equipped with a motor, a housing, a stator, a rotor, a flow directing device and other components, and the rotation speed is adjusted according to the size of the product particles. The magnesium hydroxide product has particle size of 5-200 nm, high purity and excellent fireproof performance.

Patent specification CN1536000 (published 2004-10-13) describes a nano inorganic composite flame retardant for macromolecular materials. The invention relates to a nano inorganic composite flame retardant for macromolecular materials. The flame retardant is composed of nano aluminum hydroxide, nano-structured modified aluminum hydroxide or nano magnesium hydroxide, micron-sized magnesium hydroxide and a flame retardant aid, wherein the average particle size of the nano aluminum hydroxide is less than or equal to 100 nanometers, the average particle size of the nano-structured modified aluminum hydroxide is less than or equal to 150 nanometers, the average particle size of the nano magnesium hydroxide is less than or equal to 100 nanometers, the average particle size of the micron-sized magnesium hydroxide is 1-10 micrometers, the mass ratio of the nano-sized inorganic flame retardant to the micron-sized magnesium hydroxide is 80: 20-10: 90, and the mass ratio of the nano-sized inorganic flame retardant to the micron-sized magnesium hydroxide to the flame retardant aid is 100: 10-100: 30. It can be used for flame-retardant composite materials based on PE, PP, ABS, nylon, PC, PVC, EVA, polyester and the like.

Patent specification CN1506395 (published 2004-06-23) describes the preparation of flame-retardant rigid foam polyurethanes modified with laminated silicates. The preparation method of the flame-retardant rigid foam polyurethane modified by laminated silicate comprises the following steps: uniformly mixing a polyhydroxy compound, a catalyst, a foam stabilizer, a flame retardant and other components to prepare a polyurethane composition; forcibly mixing the polyurethane composition with the surface-treated laminated nano-silicate at 30-50 ℃ for at least 30 minutes to prepare an intercalated mixture; the insertion mixture is mixed with a blowing agent at 15-25 ℃ and further polyisocyanate is added to initiate an insertion reaction to produce a rigid foamed PU material with excellent fire resistance and mechanical properties. The rigid foamed PU material of the invention has excellent flame retardant performance, high compression strength and high dimensional stability under the condition that the foaming PU does not have the plasticizing effect of an organic phosphate flame retardant and hydro-chlorofluorocarbon (hydro-chlorocarbon).

Patent specification CN1483779 (published 2004-03-24) describes a flame retardant coating and a method for its preparation. The invention discloses a flame-retardant coating material and a preparation method thereof. The composition comprises 20-40 parts of methyl or phenyl or vinyl 120-2 type silicon rubber or a mixture thereof, 3-6 parts of a crosslinking curing agent, peroxide benzoyl or di-quadrivalent (bis-di-quadrivalent) 13-25 parts of reinforced nano white carbon black and 40-60 parts of an inorganic filler. The flame-retardant coating material can be applied to PAN-based oxidized fiber flame-retardant fabrics, so that the flame-retardant property of the PAN-based oxidized fiber flame-retardant coating material is improved, and the physical property of the PAN-based oxidized fiber flame-retardant coating material can be maintained.

Patent specification WO03097735 (published 2003-11-27) describes nanoparticles in a coated product. A process for preparing an inorganic filler material coated with a nanoparticulate tin compound comprising forming a slurry of the filler material in an aqueous colloidal suspension of a tin compound, thereby precipitating the tin compound directly from the colloidal suspension onto the surface of the filler, separating the inorganic filler from the colloidal suspension, and optionally heating the coated filler to convert the hydrated tin compound to an anhydrous form. The flame retardant material consists of a particulate inorganic material coated with a nano-particulate tin product in an amount of 1 to 100 wt% based on the weight of the inorganic filler.

Patent specification CN1422925 (published 2003-06-11) describes a nano-CR-SBC composite adhesive. The invention relates to an organic adhesive which is composed of a nano composite rubber anti-aging agent, a flame retardant, resin, a plasticizer, a solvent and the like. The composite rubber adopts two kinds of nano powder, the first is nano SiO_2-XThe second being CaCO₃And the first of the two kinds of nano powder and rubber are made into composite nano rubber. The nano rubber and other materials (waymaterial) are two components, one is composed of composite thermoplastic styrene-butadiene rubber, terpene rubber, petroleum resin, modified rosin, anti-aging agent, flame retardant and solvent, and the other is composed of nano composite chloroprene rubber, 2402 resin, anti-aging agent and solvent. The method is adopted to prepare the nano-CR-SBS combined adhesive.

Patent specification WO0066657 (published 2000-11-09) describes a flame-retardant composition. A polymer composition is provided that is a combination of a polymer and a synergistic flame retardant additive that includes a nanoclay and a second filler. The second filler may be a material known for flame retardant properties, an inert filler, or a combination of both. The preferred nanoclay is Cloisite and the preferred second filler is aluminum trihydroxide. The presence of this combination of flame retardant additives in the polymer increases the strength of the char formed during combustion. The formation of hard charcoal presents a barrier to ignition of the underlying material, such as a cable that has been provided with a coating of the polymeric composition.

Patent specification JP2004331975 (published 2004-11-25) describes a flame retardant nanocomposite composition comprising a thermoplastic polymer. The flame retardant nanofiller combination of thermoplastic polymers comprises: a specific phosphoric acid ester and/or a specific diphosphoric acid ester and/or a polymer thereof as component A; and melamine condensation products and/or reaction products of melamine with phosphoric acid or polyphosphoric acid and/or reaction products of melamine condensation products with phosphoric acid or polyphosphoric acid and/or mixtures thereof as component B; and/or organic intercalated phyllosilicates, nanosphere oxides or carbon nanotubes as component C.

Patent specification KR2002010561 (published 2002-02-04) describes the use of nanoceramics for the preparation of flame retardant foams.

Patent specification WO2004108826 (published 2004-12-16) describes a curing type flame retardant epoxy resin composition. The curable flame retardant epoxy resin composition includes (a) at least one flame retardant epoxy resin; (b) at least one amphiphilic block copolymer; and (c) a curing agent. These components are present in the curable composition in suitable amounts and ratios so that, upon curing, the block copolymer self-assembles into a nanostructured morphology, such as a worm-like micellar morphology. The obtained cured product prepared from the composition of the invention has obviously enhanced fracture resistance, so that the flame-retardant epoxy resin can be applied to the application with the problem of fracture resistance.

Patent specification WO2004074361 (published 2004-09-02) describes a flame retardant composition. The invention is a flame retardant composition composed of polyolefin polymer, nano silicate, metal hydroxide and calcium carbonate. The invention also includes a coating prepared from the flame retardant composition and a wire or cable construction prepared by applying the coating to a wire or cable. The invention also includes articles prepared from the flame retardant compositions described above, such as extruded sheets, thermoformed sheets, injection molded articles, coated fabrics, roofing membranes, and wall coverings.

Patent specification WO2004056913 (published 2004-07-08) describes flame retardant polymer compositions. Disclosed is a flame retardant composition consisting of: (a) at least one particulate material which expands upon heating; and (b) at least one particulate nanofiller, and at least one polymer and/or at least one curable monomer or oligomer. The composition may also contain certain silicon-based materials. Also disclosed are flame retardant compositions comprised of polyorganosiloxanes containing one or more functional groups selected from amino, hydroxyl, methacrylic, acrylic and epoxy groups.

Patent specification WO2004013528 (published 2004-02-12) describes a conduit fitting cover consisting of preformed sheets, flexible cellular flame retardant foam or sponge which are joined together by an intumescent adhesive forming a cover to one side and dimensioned to form a reasonable snug fit around the outer wall of an open-sided conduit fitting. Each sheet was first coated with a primer comprising a sealant consisting of an aqueous solution of an acrylic copolymer containing ammonium polyphosphate, and then coated with a fluid coating of a flame retardant material. The primer solution closes the open pores of the surface and provides a binder to which the flame retardant coating can adhere.

Patent specification US2004031416 (published 2004-02-19) describes a solution for forming a flame retardant coating on a substrate of zhuruu wood comprising an aqueous alkali metal silicate solution containing about 5 wt% to about 70 wt% of an alkaline earth metal silicate, and having dispersed therein a filler in an amount of about 5-60%. The filler is preferably an intumescent material, such as graphite which is capable of exfoliation. The solution can be applied to the wood of the mine (mine) by brushing or spraying to form a coating with a thickness of 1-4 mm.

Patent specification EP1300506 (published 2003-04-09) describes a solution relating to a textile substrate with improved heat and fire resistance, which has an ignifuge coating consisting of a polymeric binder and an intumescent composition, which additionally comprises a small amount of one or more synergists acting under the influence of heat in the coating, in order to produce a fine homogeneous layer on top of the deep-bubble layer made of intumescent compound. The synergists are aluminum hydroxide, magnesium hydroxide, bauhemite, titanium dioxide, sodium silicate, zeolites, low melting glass, clay nanomolecules, borosilicate products, polyamides, polypropylene and polyester nanocomposites. The amount of synergist is 0.2-3% m/m with respect to the polymer binder.

Patent specification WO9943390 (published 1999-09-02) describes a flame retardant coating mass comprising a fluid intumescent base material having a blowing agent, a foaming agent, a charring agent, a binder, a solvent and a pigment. The coating material also includes a flame spread reducing agent, refractory fibers dispersed in a fluid intumescent base material, an oxidation limiting agent, a heat transfer limiting agent, stabilizers and volatile organic reducing substances, mechanical strengthening components for physical impact and adhesion resistance, water repellents, and elastomers to improve resistance to cracking and shrinkage and to improve sprayability.

Patent specification WO9800461 (published 1998-01-08) describes a refractory material for use in powder form as an additive to a variety of plastics, epoxies, urethanes, resins and coal tar, including an intumescent base material with a blowing agent, a blowing agent and a charring agent; a flame spread reducing agent that provides protection for up to 600 kilowatts per square meter radiant heat flux density for 5 minutes; and refractory fibers in the additive material.

Patent specification JP8253710 (published 1996-10-01) describes an intumescent coating substance having improved water resistance, fire resistance and weather resistance by adding to the material melamine coated ammonium polyphosphate particles and/or insoluble ammonium polyphosphate particles having a crosslinked surface. In this embodiment, the ammonium polyphosphate particles are heated to 300 ℃ or less for 0.5 to 5 hours to separate 5-10% of the stoichiometric ammonia m/m. Melamine is added to the heated particles at 250 ℃ and 300 ℃ to initiate addition reactions and/or to attach melamine to acid hydroxyl groups formed on the surface of the particles by separation of ammonia to give melamine coated ammonium polyphosphate particles (A). Adding a compound having a functional group reactive with the amino active hydrogen atoms of the melamine molecules on the surface of the particles A in an equivalent ratio of 0.5 to 6 of the amino groups to the particles A, and heating to 80 to 200 ℃ for a period of time necessary to form crosslinks with the surface melamine to obtain insoluble ammonium polyphosphate (B). An intumescent fire resistant coating material is prepared by mixing 100 parts by mass of a synthetic binder resin with 50-400 parts by mass of particles a and/or B.

Patent specifications EP0505940 (published 1992-09-30) and CA2063457 (published 1992-09-21) describe intumescent refractory coatings, refractory materials, and methods of making refractory materials. In this embodiment, the coating consists essentially of: (A) at least one inorganic compound selected from the group consisting of carbides, borides, nitrides, carbonitrides or carboborides of titanium, zirconium, vanadium, niobium, tantalum, molybdenum, tungsten or chromium, and calcium carbide, boron nitride or carbonitride; (B) a synthetic resin; and (C) and at least one phosphorus and/or sulfur compound capable of forming a Lewis acid upon heating.

Patent specification CN1046174 (published 1990-10-17) describes a fire retardant coating material containing a fluid intumescent material and fire resistant fibres of various sizes dispersed or suspended therein for particular uses. The fluid intumescent material includes a blowing agent, a blowing agent gas source, a carbonizing or carbonizing agent, a film forming binder, a solvent, and in some cases a pigment or filler. The refractory fibers are composed of alumina, silica, and one or more other metal oxides.

Patent specification CA2321568 (published 1999-09-02) describes a flame-retardant coating material containing a fluid intumescent base material with a foaming agent, a charring agent, a binder, a solvent and a pigment. The coating material further comprises a flame spread reducing agent; refractory fibers dispersed in the fluid intumescent base material; an oxidation limiting agent; a heat transfer limiting agent; a stabilizer and a volatile organic reducing component; a mechanical reinforcing component for physical impact resistance and adhesion; a water repellent; and an elastomer to improve resistance to crushing and shrinkage and ease of jetting.

Patent specification GB2329389 (published 1999-03-24) describes a fire-resistant coating. This solution relates to an intumescent fire-resistant coating composition consisting of one or more hydrated alkaline earth metal silicates and one or more rheology modifiers. The rheology modifier comprises elemental carbon, silicon carbide, polysaccharides or modified polysaccharides.

Patent specification US2004031416 (published 2004-02-19) describes a solution for forming a refractory coating on a substrate such as wood, which comprises an aqueous alkali metal silicate solution containing about 5-70 mass% alkali metal silicate and dispersed with about 5-60% filler. Preferably, the filler is an intumescent material such as exfoliated graphite. The solution can be applied to the wood in the mine by brushing or spraying to form a coating having a thickness of 1-4 mm.

Patent specification US5532292 (published 1996-07-02) describes an intumescent composition consisting of a mixture containing CaO, MgO and not more than 4 wt.% Al₂O₃And a salt water soluble inorganic silicate fiber material (e.g., calcium magnesium silicate). The fibers may be vitreous, have an average length of 10 to 500 microns, and may form 5 to 30 mass% of the composition. The composition may be added to a coating composition (e.g., a wet coating (paint) or a powder coating), or a mastic (mastic) or putty, or a composition containing a polymer. Can provide enhanced fire resistance and the coating composition can be applied as a single thick coating rather than building up multiple thin layers.

Patent specification CA2023932 (published 1992-02-25) discloses an intumescent coating composition comprised of an aqueous mixture of a water-soluble alkali metal silicate, a hydrated metal silicate clay and an inorganic particulate material which, when exposed to flame temperatures, absorbs heat and emits a non-flammable gas. The coating can be applied to metal, wood and foamed polymeric materials and provides a thermal barrier to overheating effects.

Patent specification GB2247420 (published 1992-03-04) describes an intumescent coating composition consisting of an aqueous mixture of a water-soluble alkali metal silicate, optionally a hydrated metal silicate clay, and an inorganic particulate material which endothermically releases a non-flammable gas when exposed to flame temperatures. The coating can be applied to metal, wood and foamed polymeric materials.

Patent specification US5035951 (published 1991-07-30) describes an intumescent coating composition comprised of an aqueous mixture of a water-soluble alkali metal silicate, a hydrated metal silicate clay and an inorganic particulate material which, when exposed to flame temperatures, endothermically releases a non-flammable gas. The coating may be applied to metal, wood and foamed polymeric materials and serves to provide a thermal barrier to overheating effects.

Patent specification US4888057 (published 1989-12-19) describes an inorganic fire resistant coating composition which expands to form a substantially continuous insulating structure when subjected to high temperatures and which maintains the structure at temperatures up to 1000 c for a long period of time. The coating composition consists of 40-70 parts by mass of sodium silicate (aqueous solution), 40-70 parts by mass of potassium silicate (aqueous solution) and 3-15 parts by mass of silicon carbide powder. Also disclosed is a composite fire retardant coating system comprised of multiple protective coatings, typically alumina, applied sequentially to a substrate to be protected. Specifically, there is a first substantially gas impermeable heat resistant adhesive layer and an inorganic intumescent layer as described above. An additional gas impermeable heat resistant layer may be included as a top coat. Additional inorganic intumescent layers may be required for some applications.

Disclosure of Invention

Despite the above listed studies on intumescent flame retardants and methods of making them, there is still a need for: a more efficient solution is obtained, promoting a more efficient fire and thermal insulation of the intumescent composition, minimising costs while maintaining its high quality.

It is an object of the present invention to provide a process which can be used to prepare intumescent flame retardants while avoiding toxic compounds, including halide derivatives. Furthermore, the object of the present invention is also to improve the flame retardancy and the thermal insulation properties of intumescent compounds, while maintaining their non-toxicity.

The present invention achieves this established objective and solves the problems encountered in the field of the preparation of intumescent flame retardants, namely, the formation of a carbonized layer at a higher rate after exposure to flame or radiant heat, and the formation of a denser carbon skeleton, improved expansibility, fire resistance and heat insulation efficiency, and the absence of toxicity and high quality of intumescent agents.

The subject of the invention is a flame retardant based on an amine-formaldehyde resin and a phosphorus-containing compound, which contains urea and/or melamine; dicyanodiamide; formaldehyde; phosphoric acid or its derivatives containing a large amount of nitrogen, in particular monoamines or diamines and/or ureas and/or melamines and/or boric acid and/or ammonium sulphate; starch or dextrin, preferably erythritol and its oligomers; and methoxylated or butoxylated melamine-formaldehyde resins, characterized by containing modifiers in the form of nanomolecules, lower alcohols and surface-active hydrating agents.

Preferably, the modifier is nano-sized silica, and the content thereof is 0.2 to 5 mass% with respect to the mass of the condensate.

Preferably, it contains the nano-scale silica introduced during the condensation as a solid or colloidal suspension.

Preferably, the silica consists of particles of 2-100 nanometers.

Preferably, the lower alcohol is methanol, ethanol or isopropanol.

Preferably, the agent contains a surface-active hydrating agent.

Preferably, the surface-active hydrating agent is 2, 4, 7, 9-tetramethyl-5-decyne-4, 7-diol.

Preferably, the expansion rate increases by 100-.

The next subject of the invention is a process for the preparation of intumescent flame retardants based on the condensation of amine-formaldehyde resins, in which the following are added with constant stirring: urea and/or melamine; dicyanodiamide; formaldehyde; phosphoric acid or its derivatives containing a large amount of nitrogen, in particular monoamines or diamines and/or ureas and/or melamines and/or boric acid and/or amine sulphate; starch or dextrin, preferably erythritol (erithrite) and its oligomers; and methoxylated or butoxylated melamine-formaldehyde resins, characterized in that nanoscale modifiers in the form of solid or colloidal suspensions are introduced during the condensation at a rate of 0.2 to 5% by mass relative to the mass of the condensate.

Preferably, the modifier introduced during the condensation is nano-scale silica.

Preferably, the lower alcohol is introduced at the end of the condensation.

Preferably, the lower alcohols introduced are methanol, ethanol and isopropanol.

Preferably, the hysteresis of the condensation process is limited to 70-100 ℃.

Preferably, the heating time of the condensation process lasts from 0.5 to 2 hours.

Preferably, a surface-active hydrating agent is introduced into the chilled condensate.

Preferably, the surface-active hydrating agent introduced is 2, 4, 7, 9-tetramethyl-5-decyne-4, 7-diol.

Detailed Description

The following are examples of the above-described embodiments of the present invention.

Example 1

A reactor equipped with a cooling system, stirrer and thermometer was charged with the following under constant stirring: 20 kg of urea, 15 kg of dicyanodiamide, 28 kg of diammonium phosphate, 4 kg of modified starch and 55dm³Formalin and 15dm³Water, and 5 kg of nanosilica as a colloidal suspension. The mixture was heated to 70 ℃ and held for 15 minutes, then the temperature was raised to 95 ℃ followed by condensation for 30 minutes. Next, 1dm was added³Isopropanol (I-propanol)Stirring was continued for 5 minutes. Then, 4 kg of methoxylated melamine-formaldehyde resin, 7 kg of ethylene glycol and 0.8 kg of surface-active hydrating agent were added to the mixture.

Example 2

A reactor equipped with a cooling system, stirrer and thermometer was charged with the following under constant stirring: 18 kg of urea, 20 kg of dicyanodiamide, 15 kg of diammonium phosphate, 10 kg of ammonium phosphate, 6 kg of dextrin and 60dm³Formalin and 15dm³Water, and 1.5 kg solid nanosilica. The mixture was heated to 70 ℃ and held for 15 minutes, then the temperature was raised to 95 ℃ followed by condensation for 30 minutes. Next, 1dm was added³Ethanol, stirring was continued for 5 minutes. The condensate was then cooled to about 30 ℃. Subsequently, 5 kg of glycerin and 0.5 kg of a surface-active hydrating agent were added to the condensate.

The efficiency of the expansion is over 10000%. For example, a 240 micron coating becomes 2.5 cm thick under the influence of radiation.

Claims (11)

1. An intumescent flame retardant based on an amine-formaldehyde resin and a phosphorus-containing compound, said flame retardant comprising urea and/or melamine; dicyanate diamides; formaldehyde; phosphoric acid or its derivatives containing a large amount of nitrogen; starch or dextrin; methoxylated or butoxylated melamine-formaldehyde resins, characterized in that they contain nanoscale silicon dioxide, a lower alcohol and a surface-active hydrating agent, and in that the surface-active hydrating agent is 2, 4, 7, 9-tetramethyl-5-decyne-4, 7-diol.

2. An intumescent fire retardant as claimed in claim 1, characterised in that said derivative of phosphoric acid containing a substantial amount of nitrogen comprises monoammonium phosphate and/or diammonium phosphate and/or urea phosphate and/or melamine phosphate.

3. An intumescent flame retardant as claimed in claim 1, characterised in that the amount of said nanoscale silica is 0.2-5% of the total condensate mass.

4. An intumescent flame retardant as claimed in any of claims 1 to 3, characterised in that it contains nano-scale silica introduced during condensation either in solid form or as a colloidal suspension.

5. An intumescent flame retardant as claimed in any of claims 1 to 3, characterised in that said silica consists of particles in the range 2 to 100 nanometres.

6. An intumescent flame retardant as claimed in claim 1, characterised in that the lower alcohol is methanol, ethanol and/or isopropanol.

7. An intumescent flame retardant as claimed in claim 1, characterised in that the intumescent efficacy varies between 100 and 20000% under the influence of radiant heat or direct contact with the flame.

8. A process for the manufacture of an intumescent flame retardant based on a condensed amine-formaldehyde resin, the process comprising: under constant stirring, the following were added: a phosphorus-containing compound comprising urea and/or melamine; dicyanate diamides; formaldehyde; phosphoric acid or its derivatives containing a large amount of nitrogen; starch or dextrin; methoxylated or butoxylated melamine-formaldehyde resins, characterized in that nanoscale silica is introduced in solid form or as a colloidal suspension during the condensation in an amount of 0.2 to 5% by weight of the total condensate mass, a lower alcohol is introduced at the end of the condensation and a surface-active hydrating agent is introduced into the cooled condensate, wherein the surface-active hydrating agent is 2, 4, 7, 9-tetramethyl-5-decyne-4, 7-diol.

9. The method of claim 8, wherein the derivative of phosphoric acid containing a substantial amount of nitrogen comprises monoammonium phosphate and/or diammonium phosphate and/or urea phosphate and/or melamine phosphate.

10. The process according to claim 8 or 9, characterized in that the introduced lower alcohol is methanol, ethanol and/or propanol.

11. The method according to claim 8 or 9, characterized in that the heating time during condensation is limited to 0.5-2 hours.