Novel cellular isocyanate reaction products and processes therefor

Abstract

Abstract Foamed isocyanate reaction products, which are polyureas or polyurea-polyurethanes, are prepared by reacting: (1) at least one organic polyisocyanate, with (2) at least one long chain (mol. wt. 500 to 6000) organic polymer having groups reactive with isocyanate groups which are separated by a polymeric chain and at least some of which are primary or secondary amino, in the presence of (3) a blowing agent. Component (2) preferably is a mixture of a polymeric polyamino compound wherein the amino groups are terminal, with a polyalkylene ether polyol. Polyamino compounds are preferably free of other isocyanate-reactive groups, but may have such groups present. When component (2) comprises only a polyamino compound, the reaction is inconveniently rapid. This may be avoided: (1) by mixture of the reactants using a salt form of the polyamino compound and subsequently activating this compound by addition to the reaction mixture of a base; or (2) by using carbon dioxide as a blowing agent, which inactivates part of the polyamino compound in the carbamate form; alternatively very rapid mixing procedures may be employed. Polyisocyanates used may be those conventionally employed in such reactions or pre-polymers with isocyanate groups derived by reacting glycols, glycerol or polyether polyols with an excess of diisocyanate; also present may be catalysts, such as aliphatic, aromatic and heterocyclic tertiary amines, Lewis acids, inorganic bases, and certain organo metallic complexes. Blowing agents may be carbon dioxide, per se or produced by addition of water which reacts with the isocyanate groups, fluorocarbons, and volatile alkanes, alkenes, halogenated alkanes, ethers, or alkyl ketones. Other ingredients of the reaction mixture may be surfactants, particularly polysiloxane - oxyalkylene block copolymers, fillers, emulsifiers, pigments, plasticizers, stabilizers and flame retardants. Suitable polyamino compounds are: (1) Amino-terminated polyalkylene ethers of formula <FORM:1049644/C3/1> wherein R is C2 to C10 alkylene, R1 is H, alkyl, aryl, or aralkyl, R111 is a di-, tri- or tetra-valent hydrocarbon radical derived from a polyhydroxy-organic compound, n is 2 to 10, x is an integer appropriate to the aforesaid molecular weight range, and z is 2 to 4 being equal to the valence of R111; (2) Amino-esters of hydroxy-terminated polyalkylene ethers, corresponding to the above formula, wherein the amino group is replaced by an amide grouping; (3) Di-(amino-esters) of hydroxy-terminated long chain aliphatic hydrocarbons, derived from polydienes, of formula <FORM:1049644/C3/2> wherein R11 is alkylene, and R1 is a polydiene or hydrogenated polydiene moiety; (4) Polydiene diamines of formula <FORM:1049644/C3/3> wherein R1 and R1 are as above defined. Polyether polyols having a mol. wt. from 600 to 6000 and 2 to 4 reactive hydroxyls which are useful as forming a part of component (2) above may be obtained by polymerization or co-polymerization of alkylene oxides, substituted oxetanes, glycols or heterocyclic ethers; e.g. tetrahydrofuran polymerized to a polytetra-methylene ether glycol by catalytic amounts of fluorosulphonic acid, and glycols polymerized in the presence of fuller's earth, sulphonic acids or mineral acids. Linear polyalkylene ether polyols have 3 to 8 or more carbons in their alkylene groups; the corresponding branched chain polyols may be obtained by reacting glycols or alkylene oxides with, e.g. sucrose, sorbitol, styrene-vinyl alcohol copolymers, hexanetriol, pentaerythritol, glycerol, phloroglucinol, trimethylol phenol, trimethylol pentane or trimethylol benzene. Examples are given for formation of foamed products by the reaction of suitable polyisocyanates with the following: (1) A polyether propylene diamine having a M.W. of 1205 and terminal amino groups; (2) A mixture of polypropylene oxide-glycerol adduct with a diamine as in (1); (3) to (6) As for (2) using different proportions etc.; (7) A mixture of polypropylene oxide-glycerol adduct with a polypropylene oxide adduct of 1,2,6-hexanetriol, M.W. 4800, with three terminal amino groups; (11) A polypropylene-glycerol adduct with a diester of p-aminobenzoic acid and polybutadiene glycol. Also exemplified are the following preparative procedures: (a) A polypropylene glycol, M.W. 425, is reacted with acrylonitrile with potassium hydroxide in ethylene glycol, and the nitrile produced is hydrogenated to give a product which, after methanolic alkaline hydrolysis, is a terminal diamino compound of M.W. 539; (b) A compound is prepared by the analogous procedure from a polytetramethylene ether glycol, M.W. 970, to give a diamine of M.W. 1086; (c) Two polypropylene ether triols of M.W. 3000 and 4000, respectively prepared by the base-catalysed condensation of propylene oxide and glycerol, and the condensation of this product with ethylene oxide, are similarly converted to mixed primary and secondary amines; (d) A polytetramethylene ether glycol is reacted with p-nitrobenzoyl chloride in pyridine, and the product hydrogenated to yield a diamine of M.W. 1210; (e) A hydroxy-terminated polybutadiene, M.W. 1340 is reacted with p-nitrobenzoyl chloride and the product hydrogenated to give a diamine of M.W. 1578; (f) Low molecular weight dimetallo-diacids are prepared from polybutadiene disodium adduct by addition of carbon dioxide, and are converted to polydienes with primary or secondary amino end groups of M.W. 500 to 6000 by addition of unsubstituted or substituted cyclic imines.

Inventors

No inventors recorded.

Bibliographic Details