DE4109076A1 - METHOD FOR THE PRODUCTION OF URETHANE AND PRIMARY ISOCYANURATE GROUPS OF HARD FOAM MATERIALS AND THEIR USE AS DAEMING MATERIALS - Google Patents

Abstract

Halogen-free hard foam substances containing urethane groups and predominantly isocyanurate groups are prepared by reacting a) polyisocyanates with b) compounds having a molecular weight of 400 to 10'000 and containing at least two hydrogen atoms which react with isocyanates and c) possibly compounds having a molecular weight of 32 to 399 and containing at least two hydrogen atoms which react with isocyanates in the presence of d) trimerization catalysts and e) water and/or hydrocarbons as foaming agents and f) phosphorylated fireproofing materials, possibly in the presence of g) additional foaming agents and additional process materials and additives, at a characteristic number of 80 to 400, preferably 100 to 300. All chemical compounds used, in particular the fireproofing materials and foaming agents, are halogen free. The compounds so prepared are used as insulating materials.

Description

The present invention relates to halogen-free, flame protected rigid foams that weighed urethane and have isocyanurate groups.

As a rule, in the production of polyurethane Rigid foams various halogen-containing compounds uses. These are fluorine-chlorine Hydrocarbons used as a blowing agent for training of cellular structures. Be further halogenated chemical compounds used to the Increase flame retardancy of rigid foams.

In general, however, the processing of such halogen containing substances in rigid foams as problema discussed, especially since their disposal by recycling or by burning the old substances in waste incineration plants.

The task was therefore to develop a process for the production of Finding rigid foams that don't have these problems have, but on the other hand the rigid foams good insulation properties and required for construction applications Have flame retardant properties.

Such products have already been described in EP-A 03 08 733. According to the invention, these are rigid PUR foams with a characteristic number range of 85-150, which are preferably driven by the carbon dioxide generated from the water-isocyanate reaction. In order to be able to process reliably, raw densities of not less than 40 kg / m ^{3 are} common with such rigid foams, since otherwise there is a risk of shrinkage or shrinkage. In addition, the foams show poor aging behavior of the thermal insulation properties, caused by the rapid diffusion of carbon dioxide from the cells, as well as the slow diffusion of air into the cells. Permanently good insulation is only possible with such foams if diffusion-tight cover layers are processed.

Halogen-free Har is also already in EP-A 03 94 769 described foams. For the driving reaction Pentane as halogen-free but flammable coal water used. Therefore, considerable efforts had to be made be undertaken to meet the requirements for building materials To ensure flame retardancy. In this EP-A uses dimethyl methane phosphonate (DMMP), against which there are significant environmental concerns, and  the use of which should be avoided. Furthermore solid flame retardants are used at room temperature uses, but their processing technical problems poses.

It has also been tried to be ecologically sound Hard foam by making the Flammwi due to the incorporation of polyisocyanurate structures elevated. Carbon dioxide is used as a blowing agent generated from the water-isocyanate reaction. As above described, carbon dioxide can only be used in the Ver work diffusion-proof cover layers a long time guarantee a low coefficient of thermal conductivity.

To ensure a permanently low coefficient of thermal conductivity is therefore necessary to use a cell gas that stays in the cell permanently. Hydrocarbons have this property, but worsen it The flame retardancy of the rigid foams is considerable.

Surprisingly, it has now been found that with it itself halogen-free phosphorus compounds in recipes higher metrics using hydro such rigid foams can be produced.

The invention relates to a method for the manufacture urethane and predominantly isocyanurate groups having rigid foams by implementing

• a) with polyisocyanates  
• b) Compounds with at least two compared to Isocya naten active hydrogen atoms of molecular weight weight 400 to 10,000 and
• c) optionally compounds with at least two hydrogen reactive to isocyanates atoms and a molecular weight of 32-399, in Presence of
• d) trimerization catalysts and
• e) water and hydrocarbons as propellants and
• f) phosphorus-containing flame retardants, if appropriate in the presence of
• g) other blowing agents and others per se known auxiliaries and additives

with a key figure of over 200, preferably 210 to 400, characterized in that all used chemical compounds, especially flame retardants agents and blowing agents that are halogen-free.

It is preferred according to the invention that

• - As a hydrocarbon blowing agent, pentane and / or Isopentane is used
• - The phosphorus-containing flame retardants Are liquid at room temperature,  
• - Benzyl-n-butyl phthalate used as an emulsifier becomes,
• - As an emulsifier containing hydroxyl groups OH number 85 polyether made by Ethoxylation of nonylphenol is used.

The invention also relates to the use of the urethane and Hart having predominantly isocyanurate groups foams as insulation materials.

The production of urethane and mainly isocyanurate group-containing foams is known per se and Z. B. in DE-PS 11 12 285, GB-PS 11 04 394, DE-OS 15 95 844 and 17 69 023 as well as in the plastic manual Volume VII, Polyurethane, published by Vieweg and Höchtlen, Carl Hanser Verlag Munich 1966 and in the New edition of this book, edited by G.Oertel, Carl Hanser Verlag Munich, Vienna 1983.

The following are used to manufacture the foams:

• a) As starting components aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanates such as z. B. by W. Siefken in Justus Liebigs Annalen der Chemie, 562, pages 75 to 136, for example those of the formula Q (NCO) _n , n = 2-4, preferably 2-3, and Q having an aliphatic hydrocarbon radical 2-18, preferably 6-C-atoms, a cycloaliphatic hydrocarbon residue with 4-15, preferably 5-10 C-atoms, an aromatic hydrocarbon residue with 6-15, preferably 6-13 C-atoms or an araliphatic hydrocarbon residue with 8-15, preferably 8-13 carbon atoms, z. B. such polyisocyanates as described in DE-OS 28 32 253, pages 10-11. The technically easily accessible polyisocyanates, for. B. the 2,4- and 2,6-tolylene diisocyanate, and any mixtures of these Ge isomers ("TDI"); Polyphenylpoly methylene polyisocyanates, such as those produced by aniline-formaldehyde condensation and subsequent phosgenation ("crude MDI") and cariimide groups, urethane groups, allophanate groups, isocyanurate groups, urea groups or biuret groups-containing polyisocyanates ("modified polyisocyanates"), in particular such modified polyisocyanates which are derived from 2,4- and / or 2,6-tolylene diisocyanate or from 4,4'- and / or 2,4'-diphenylmethane diisocyanate.
• b) Starting components are also connections with at least two areocyanate-reactive capable hydrogen atoms of one molecular weight usually from 400-10 000. Below one understands beside amino groups, thio groups or Compounds containing carboxyl groups preferred wise hydroxyl-containing compounds, in particular having 2 to 8 hydroxyl groups Compounds, especially those of molecular weight 1000 to 6000, preferably 2000 to 6000, e.g. B. at least 2, usually 2 to 8, preferably but polyethers having 2 to 6 hydroxyl groups and polyester, and polycarbonate and polyester amides as they are used for the production of homogeneous and of cellular polyurethanes known per se are and how they z. B. in DE-OS 28 32 253, Pages 11-18.
• c) If necessary, there are further starting components Connections with at least two compared to Iso cyanate reactive hydrogen atoms and a molecular weight of 32 to 399. Also in in this case, this means hydroxyl groups and / or amino groups and / or thiol groups and / or compounds containing carboxyl groups preferably hydroxyl groups and / or amino groups having connections, the sls chain extensions agents or crosslinking agents.

These compounds usually have 2 to 8, preferably 2 to 4, over isocyanates  reactive hydrogen atoms. Examples for this purpose, DE-OS 28 32 253, pages 19-20, described.

• d) According to the invention, those known per se Trimerization catalysts also used.
• e) According to the invention, phosphorus-containing, halogen-free flame retardants such as triethylphos phate, diphenyl cresyl phosphate, red phosphorus puts.
• f) Water and hydrocarbons, preferably C ₃ -C ₇ -alkanes, particularly pentane and isopentane, are used as blowing agents.
• g) If necessary, auxiliaries and additives are used as well
  • further volatile organic substances as additional blowing agents,
  • - Additional catalysts of the type known per se in amounts of up to 10% by weight, based on the amounts of component b)
  • surface-active additives, such as emulsifiers and foam stabilizers,
  • - Response delay, e.g. B. acidic substances such as hydrochloric acid or organic acid halides, further cell regulators of the type known per se such as paraffins or fatty alcohols or dimethylpolysiloxanes as well as pigments or dyes further stabilizers against the effects of aging and weathering, plasticizers and fungistatic and bacteriostatic substances and fillers such as barium sulfate, Diatomaceous earth, soot or sludge chalk.

If necessary, these auxiliary and Additives are described, for example, in DE-OS 27 32 292, pages 21-24.

Further examples of optionally according to the invention surface active additives to be used and Foam stabilizers and cell regulators, reaction ver delay, stabilizers, flame retardant substances, Plasticizers, dyes and fungistatic and bacteriostatically active substances and details about the use and mode of action of these additives are published in the plastic manual, volume VII by Vieweg and Höchtlen, Carl-Hanser-Verlag, Munich 1966, e.g. B. described on pages 103-113.

Carrying out the process for producing the foam materials:
The reaction components are implemented according to the known one-stage process, the prepolymer process or the semi-prepolymer process, often using mechanical devices, e.g. B. those described in US Pat. No. 2,764,565. Details about processing devices, which are also possible according to the invention, are in the plastics manual, volume VII, edited by Vieweg and Höchtlen, Carl-Hanser-Verlag, Munich 1966, z. B. on pages 121 to 205.

Of course, foams can also Block foaming or according to the known Double conveyor belt processes are manufactured.

The products available according to the invention are found e.g. B. as insulation boards for roof insulation application.

Examples

The following mixtures were produced: Polyol component A 100 parts by weight (GT) of a polyol mixture of the OH number 265 with a viscosity of 3100 mPas at 20 ° C, consisting of:

• 1. 20 pbw of a polyether having an OH number of 375 by propoxylation of a mixture of sugar, Propylene glycol and water.
• 2. 30 pbw of a polyester of OH number 210 based Adipic anhydride, phthalic anhydride, glycerin and propylene glycol
• 3. 4 pbw of a polyester with an OH number of 685 by reacting phthalic anhydride with Diethylene glycol
• 4. 5 pbw of a polyether of OH number 640, prepared by reacting ethylenediamine with a Mixture of ethylene oxide and propylene oxide
• 5. 6 pbw of a polyether having an OH number of 185 by ethoxylation of propylene glycol
• 6. 3 GT glycerin
• 7. 30 pbw of diphenyl cresyl phosphate as a flame retardant  
• 8. 1.5 pbw of a commercially available polyether polysiloxane Foam stabilizer (Tegostab B8421, Goldschmidt AG, Essen)
• 9. 0.5 pbw of a commercially available polyether polysiloxane Foam stabilizer (Tegostab B8443, Goldschmidt AG, Essen)

Polyol component B

100 pbw of a polyol mixture of OH number 265 with one Viscosity of 340 mPa · s at 20 ° C according to the Polyol component A, in which the flame retardant Diphenyl cresyl phosphate by the same amount of Flame retardant triethyl phosphate has been replaced.

The polyol components A and B thus produced were according to the recipes listed in the table with different key figures for rigid polyurethane foam fabrics with polyisocyanurate structures processed.

Polyol component C

100 pbw of a polyol mixture of OH number 185 with one Viscosity of 1900 mPa · s at 25 ° C, consisting of:

• 1. 50 pbw of a polyester based on OH number 370 Phthalic anhydride, adipic acid, oleic acid and Trimethylolpropane  
• 2. 15 pbw of benzyl n-butyl phthalate
• 3. 35 pbw of diphenyl cresyl phosphate as a flame retardant
• 4. 1.6 pbw of a commercially available polyether polysiloxane Foam stabilizer (Tegostab B 8443, Goldschmidt AG, Essen)

Poly component D

100 pbw of a polyol mixture of CO number 185 with one Viscosity of 200 at 25 ° C according to the polyol component C, in which the flame retardant diphenyl cresyl phosphate by the same amount of flame retardant was replaced with triethyl phosphate.

The polyol components A and B represent typical ones Mixtures such as those used in the manufacture of insulation boards and Serve composite elements on double conveyor belt systems. Formulations C and D represent typical ones Mixtures such as those used for the production of block foam serve.

From the results of the tables it can be seen that regardless of the type of flame retardant, the rigid foams with a key figure above 200 meet the requirements for classification B2 according to DIN 4102 (small burner test). In contrast, rigid foams with a key figure below 200 can only be classified in class B3.

Table 2

Claims (7)

1. Process for the production of urethane and rigid isocyanurate groups having rigid foam materials by reacting

• a) with polyisocyanates
• b) compounds with at least two isocyanate-active hydrogen atoms with a molecular weight of 400 to 10,000 and
• c) optionally compounds with at least two isocyanate-reactive hydrogen atoms and a molecular weight of 32-399, in the presence of
• d) trimerization catalysts and
• e) water and hydrocarbons as propellants and
• f) phosphorus-containing flame retardants, optionally in the presence of
• g) further blowing agents and other auxiliaries and additives known per se

with a key figure of over 200, preferably 210 to 400, characterized in that all turned put chemical compounds, especially the Flame retardants and blowing agents, halogen-free are.   2. The method according to claim 1, characterized in that that as a hydrocarbon blowing agent pentane and / or isopentane is used. 3. The method according to claim 1 and 2, characterized records that the phosphorus-containing flame retardant are liquid at room temperature. 4. The method according to claims 1-3, characterized records that benzyl-n-butyl phthalate as an emulsifier is used. 5. The method according to claims 1-3, characterized records that a hydroxyl group as an emulsifier polyether having the OH number 85, prepared by ethoxylation of nonylphenol becomes. 6. Use obtained according to claims 1 to 5 urethane and predominantly isocyanurate groups having rigid foams as insulation materials.