Polymethylene polyphenylamine modified diamine chain extenders and polyurea elastomers therefrom.

摘要

Reaction injection molded polyurea elastomers are disclosed that are derived from the reaction of (1) an aromatic polyisocyanate (2) primary or secondary amine terminated polyethers and (3) an aromatic amine extender combination comprising (a) an aromatic diamine having at least one of the positions ortho to each amine group substituted by a lower alkyl group and (b) a polymethylene polyphenylamine. The use of the polymethylene polyphenylamine component allows for the retention of the good physical properties of the prior art polyureas while at the same time effecting a cost reduction in the preparation of this useful class of polymers.