Patent GB-1009956-A (GB)
Title: Novel resins
IPC: C08G73/14
Filed: 1962-07-02
Abstract: A process for the production of a resin comprises reacting an acid anhydride reactant having a benzene, naphthalene, diphenyl, diphenyl ketone or diphenyl ether nucleus bearing as the reactive substituents: (1) an acid or hydride group, and (2) a carboxyl, hydroxyl, acid anhydride or primary or secondary amino group, with an isocyanate having at least two isocyanate groups on a benzene, naphthalene, diphenyl, diphenyl alkane (where the alkane portion has not more than 3 carbon atoms), diphenyl ketone, diphenyl ether, alkane (having not more than 8 carbon atoms) or cycloalkane (having 5 to 7 carbon atoms) nucleus, by dissolving the said acid anhydride with agitation in the polyisocyanate which is in the liquid state to form an homogeneous liquid solution containing the reactants in a molar ratio of polyisocyanate to anhydride of 1 : 1 to 2 : 1, heating and agitating the liquid solution to release gas being formed by the reaction, the heating and agitation being continued for a time from about the point of formation of the homogeneous liquid solution to substantially short of the point at which the liquid in the reaction zone forms an expanding foamy mass, cooling the liquid to obtain a resin product, the resin being characterized by a progressive decrease in solubility in organic solvents as the time of reaction is increased. In a modification of the product, a cellular product is produced by continuing the heating and agitation until a liquid of predetermined high viscosity is present in the reaction zone, terminating the heating and agitation, permitting the viscous liquid to react with the consequent production of gas thereby forming an expanding foamy mass which is solidified. Specified anhydride reactants are trimellitic anhydride, hemimellitic anhydride, pyromellitic dianhydride, the anhydride of N-carboxy anthranolic acid, hydroxy phthalic anhydride, aminophthalic anhydride, methyl trimellitic anhydride, aminonaphthalene-1 : 8-dicarboxylic anhydride, 41 - carboxy diphenyl - 3 : 4 - dicarboxylic anhydride, di-(phenyl dicarboxylic anhydride) ketone and di-(phenyl dicarboxylic anhydride) ether.  Specified polyisocyanates and diphenyl methane-4 : 41-diisocyanate, 2 : 4-tolylene diisocyanate, xylylene diisocyanate, naphthalene diisocyanate, diphenyl diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, octane - 1 : 8 - diisocyanate, cyclohexane diisocyanate and polyphenyl polymethylene polyisocyanate.  Catalysts and accelerations, e.g. cobalt naphthenate, cobalt acetate, N - ethyl - morpholine, N - coco - morpholine, lithium ricinoleate, sodium oleate, primary and secondary amines or fatty acid amides may be present in the reaction mixtures. In the preparation of cellular products, siloxanes, e.g. polymethyl siloxanes or polyphenyl methyl siloxanes may also be present in the reaction mixtures.  In the examples, cellular materials are made by reacting (1) to (4) diphenyl methane-4 : 41-diisocyanate with trimellitic anhydride; (5) diphenyl methane-4 : 41-diisocyanate with pyromellitic dianhydride; (6) trimellitic anhydride and hexamethylene diisocyanate; (7) diphenylmethane diisocyanate and isatoic anhydride; (8) trimellitic anhydride, isophthalic acid and diphenyl methane diisocyanate; (9) trimellitic anhydride and methylene diphenyl diisocyanate in the presence of naphtha and cobalt naphthenate; (10) diphenyl methane diisocyanate and trimellitic anhydride in the presence of polymethylphenyl siloxane and polyalkyl or polyalkyl aryl siloxane having ether and/or hydroxyl groups; (11) diphenyl methane diisocyanate, trimellitic anhydride, N-ethyl morpholine and the siloxanes of Example (10): (12) trimellitic anhydride and diphenyl methane diisocyanate, and (13) trimellitic anhydride and polymethylene polyphenyl isocyanate in the presence of a siloxane.