Process for the production of cross-linked polyurethane plastics of high molecular weight

摘要

In a process for the production of cross-linked polyurethane plastics of high molecular weight from reaction products of linear condensation and/or polymerization products containing hydroxyl groups and having a molecular weight exceeding 1000, diisocyanates and, if desired, compounds having two reactive hydrogen atoms and a molecular weight lower than 1000, a reaction product produced by the use of such a diisocyanate and/or, if desired, such a compound having two reactive hydrogen atoms and a molecular weight lower than 1000, as contains a group group at least once in the molecule, is cross-linked with an organic peroxide at a temperature exceeding 100 DEG C. The group must fulfil the following conditions: (a) the group must form part of a cycloaliphatic or heterocyclic ring; (b) the group must be bonded to two carbon atoms in a -, b -position which are common to an aromatic ring; (c) the substituent R must be a hydrogen atom or an aliphatic hydrocarbon radical which may be substituted. Polyesters and polyethers are suitable compounds of molecular weight above 1000. The polyesters may be obtained from the glycols containing -CHR- groups. Toluylene, 4, 41-diphenylmethane, hexamethylene, p-phenylene and 1, 5-naphthylene diisocyanates are specified. Aliphatic and cycloaliphatic glycols are listed for the compounds of molecular weight below 1000. Specified compounds containing the group -CHR-, to replace all or part of the diisocyanates and/or the compound of molecular weight below 1000 are N, N-di-(b -hydroxyethyl)-5, 6, 7, 8-tetrahydronaphthylamine-(1) or -(2); 2-(2, 3-dihydroxypropyloxy)-5, 6, 7, 8-tetrahydro-naphthalene; 2-N, N-di-(b -hydroxyethyl) sulphonamido-5, 6, 7, 8-tetrahydronaphthalene; 3, 6-diisocyanato-thioxanthene-S-dioxide; 2, 7-diisocyanatofluorene; 1, 4-di(b -hydroxyethoxy)-5, 6, 7, 8-tetrahydronaphthalene; 9, 10-di(b -hydroxyethoxy) octahydroanthracene and the compound of formula: For the cross-linking dicumyl, benzoyl, methyl ethyl ketone, diacetyl and succinyl peroxides and cumene and cyclohexanone peroxides are suitable. Fillers, such as carbon black, and lubricants, such as stearic acid, may be incorporated. In an example a mixture of polybutylene glycol and N, N-di-(b -hydroxyethyl)-5, 6, 7, 8-tetrahydronaphthylamine-(2) is reacted with toluylene diisocyanate. The resulting thermoplastic product is mixed with carbon black, stearic acid and dicumyl peroxide and the mixture is cured at 150 DEG C.