Abstract: A process is described for the preparation of polymethylene polyphenyl polyamines containing from 40 to 60 percent by weight of diamine and also containing markedly less high molecular weight polyamines than products hitherto available. Phosgenation of the polyamines gives the corresponding mixture of polymethylene polyphenyl polyisocyanates of markedly lower viscosity and lighter color than products hitherto available, and yielding polymer foams which are substantially white in color.The process comprises condensing aniline and formaldehyde (molar ratio 4-10:1) in the absence of catalyst, separating water from the resulting aminal mixture, contacting the aminals at 20.degree. C to 60.degree. C with a solid catalyst (diatomaceous earths, clays, zeolites) until formation of benzylamines is substantially complete, distilling aniline from the resulting benzylamines under reduced pressure and below 150.degree.

Abstract: Aniline and formaldehyde are condensed (2-10 moles aniline per mole of formaldehyde) at ambient temperature in the absence of acid catalysts to give a mixture of aminals (anilinoacetals) and aniline from which the water is removed. The anhydrous aminals are contacted with a solid catalyst (clays, zeolites, diatomaceous earth) using either batch or continuous operation initially at 20.degree. C to 55.degree. C until benzylamine formation is substantially complete, then at 50.degree. C to 65.degree. C until benzylamine conversion to methylene polyphenyl polyamines is 75 - 90% complete and finally at 80.degree. C to 100.degree. C. A polyamine mixture is obtained in which diaminodiphenylmethane is the major (order of 90 percent by weight or higher) component, the bulk of the higher oligomeric polyamines being triamine. The diaminodiphenylmethane component contains of the order of 85 percent of 4,4'-isomer, the rest being 2,4'-isomer except for very small amounts (order of 2 percent or less) of 2,2'-isomer.

Abstract: Polyisocyanurate foams are disclosed which are characterized by low Flame Spread Ratings and low smoke generation values, as determined by the Underwriter's Laboratory Tunnel Test in accordance with the ASTM E-84 test procedure. The smoke and flame resistant properties are achieved, not through the use of flame retardants or additives, but rather by the use of a minor amount of a hydroxyl terminated aromatic polyester having a hydroxyl equivalent weight from about 150 to about 500 and which is the product of the reaction of an excess of a polyethyleneglycol having an equivalent weight from about 75 to about 225, with an aromatic polycarboxylic compound.

Abstract: A process is described for the preparation of polymethylene polyphenyl polyamines containing from 40 to 60 percent by weight of diamine and also containing markedly less high molecular weight polyamines than products hitherto available. Phosgenation of the polyamines gives the corresponding mixture of polymethylene polyphenyl polyisocyanates of markedly lower viscosity and lighter color than products hitherto available, and yielding polymer foams which are substantially white in color.The process comprises condensing aniline and formaldehyde (molar ratio 4-10:1) in the absence of catalyst, separating water from the resulting aminal mixture, contacting the aminals at 20.degree. C to 60.degree. C with a solid catalyst (diatomaceous earths, clays, zeolites) until formation of benzylamines is substantially complete, distilling aniline from the resulting benzylamines under reduced pressure and below 150.degree.

Abstract: Novel bituminous compositions are disclosed which are characterized by elevated Ring and Ball softening points ranging up to about 200.degree. C. They are prepared by the treatment of molten bitumen, in the absence of solvent, with a combination of: (a) an amine selected from the class consisting of an aliphatic amine having from 10 to 20 carbon atoms, and aromatic polyamines; and (b) an isocyanate selected from the class consisting of aliphatic isocyanates having from 10 to 20 carbon atoms, and aromatic polyisocyanates; provided that in any instance in which the amine component is aliphatic, then the isocyanate component is aromatic. The combined weight of (a) and (b) present in the bitumen, is from about 1 to about 10 weight percent based on the weight of bitumen. The bituminous compositions are useful in paving, and roofing applications, especially in countries which experience hot climates.

Abstract: A process is described for the selective removal of 2,2'- and 2,4'-diaminodiphenylmethanes from mixtures containing 2,2'-, 2,4'- and 4,4'-diaminodiphenylmethanes and polyamines by heating these mixtures in the presence of aqueous hydrochloric acid (55 to 95 percent by equivalents based on the total amine in the starting material) and formaldehyde. The process is particularly useful to facilitate the isolation of substantially pure 4,4'-isomer from aniline-formaldehyde condensation products. The pure 4,4'-isomer is a valuable intermediate for polyamides as well as for the corresponding diisocyanate. The by-products of the reaction are oligomeric polymethylene polyphenyl polyamines which are also useful as curing agents and intermediates for polymethylene polyphenyl polyisocyanates and the like.

Abstract: A process is described for the selective removal of 2,2'- and 2,4'-diaminodiphenylmethane from mixtures thereof with the corresponding 4,4'-isomer by heating the mixture of isomers in the presence of a 1,3,5-tri-arylhexahydro-1,3,5-triazine and a catalyst (aqueous mineral acid). The process is particularly useful in facilitating the isolation of substantially pure 4,4'-isomer from the aniline-formaldehyde condensation. The pure 4,4'-isomer is a valuable intermediate for polyamides as well as for the corresponding diisocyanate. The by-products of the reaction are oligomeric polymethylene polyphenyl polyamines which are also useful as curing agents and intermediates for polymethylene polyphenyl polyisocyanates and the like.

Abstract: 2,2'- AND 2,4'-DIAMINODIPHENYLMETHANE ARE SELECTIVELY REMOVED FROM ADMIXTURES THEREOF WITH THE 4,4'-ISOMER BY HEATING THE ISOMER MIXTURE AT 30.degree. TO 100.degree. C in the presence of styrene, .alpha.-alkylstyrenes, or the mono- or diamino nuclear substituted derivatives thereof and a catalyst (mineral acid, clays, diatomaceous earth, zeolites). The styrene or .alpha.-alkylstyrene can be employed as such or generated in situ from a precursor therefor. The process is particularly useful in facilitating the isolation of substantially pure 4,4'-diaminodiphenylmethane from the polyamine mixture obtained by condensation of aniline and formaldehyde.

Abstract: A novel catalyst combination for the trimerization of polyisocyanates to polyisocyanurates is disclosed. The catalyst combination comprises (i) a tertiary amine trimerization catalyst containing a dimethylamino moiety, (ii) an alkali metal salt of an N-(2-hydroxyphenyl)methyl glycine, and (iii) a monomeric epoxide. The use of these catalysts in the preparation of polyisocyanurate foams results in facile machine preparation of bun stock foam without incurring the processing problems that arise from the prior art method. The polyisocyanurate foams produced using the novel catalyst combination of the invention are characterized by a reduced level of smoke generated on combustion.

Abstract: A process is described for recovering phenylcyclohexane as principal product from dicyclohexylbenzenes by heating the latter in the presence of at least an equal amount by weight of benzene and an acid clay or zeolite catalyst at a temperature of 190.degree. - 400.degree.C. The period of heating is preferably controlled so that no significant cracking of the phenylcyclohexane is caused. The process is a useful adjunct to the known methods of production of phenylcyclohexane by hydrodimerization by benzene. The latter process gives significant amounts of dicyclohexylbenzenes as by-product. The present process enables this generally undesirable by-product to be converted to phenylcyclohexane thus increasing the overall yield of phenylcyclohexane from benzene in the hydrodimerization process.