Binders for waste rubber chips. (Mitsui-Nisso Urethane K. K., Japan). Jpn. Kokai Tokkyo Koho JP 58142836 A2 25 Aug 1983 Showa, 4 pp. (Japanese). (Japa…

Binders for waste rubber chips. (Mitsui-Nisso Urethane K. K., Japan). Jpn. Kokai Tokkyo Koho JP 58142836 A2 25 Aug 1983 Showa, 4 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: B29H019-00; B29H003-00; C09J003-16. ICA: C08K005-09; C08L075-04. APPLICATION: JP 82-23576 18 Feb 1982. DOCUMENT TYPE: Patent CA Section: 39 (Synthetic Elastomers and Natural Rubber) Pot life of urethane prepolymer binders for waste tire rubber chips is improved by adding 0.1-10% (based on prepolymer) carboxylic acid halides. Thus, 660 g polypropylene glycol (av. mol. wt. 3000) and 340 g diphenylmethane 4,4'-diisocyanate were heated 2 h at 80° to give prepolymer (I) [9048-57-1]. A compn. of 4 parts of 1-3 mm-diam. waste tire rubber chips and 1 part binder ( mixt. of I and benzoyl chloride [98-88-4]) having pot life (35°, relative humidity 70%) 3.0 h was formed into a 7-8-mm sheet and left 48 h in a chamber at 50° and relative humidity 70% to cure. The sheet had tensile strength 16 kg/cm2, elongation 100%, and tear strength 16 kg/cm.Except for chemicals metioned above, 112-67-4 and 618-32-6 are also used. .