Reference

Nontoxic propylene-tetrafluoroethylene rubber vulcanizates

Nontoxic propylene-tetrafluoroethylene rubber vulcanizates. Kojima, Gen (Asahi Glass Co., Ltd., Japan). Japan. Kokai JP 52136251 14 Nov 1977 Showa, 5 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: C08L027-18. APPLICATION: JP 76-52823 11 May 1976. DOCUMENT TYPE: Patent CA Section: 38 (Elastomers, Including Natural Rubber) Propylene-tetrafluoroethylene copolymer (I) [27029-05-6] is vulcanized in the presence of peroxides 0.1-20, polyfunctional compds. 0.1-20, and TiO2 or BaSO4 0.1-100 wt.% (based on I) to give nontoxic elastomers. Thus, a compn. of (molar) I (mol. wt. 18 ′ 104) 100, di-Bu peroxide [3849-34-1] 2, triallyl isocyanurate [1025-15-6] 3, and BaSO4 20 parts was pressed 30 min at 160° and heated 2 h in an oven at 200° to give white test pieces having tensile strength 198 kg/cm2, elongation 420%, 100% modulus 25 kg/cm2, Shore A hardness 68, and KMnO4 consumption (Welfare Ministry No. 434) 0.7 ppm.

Peroxide-curable fluoroelastomers

Peroxide-curable fluoroelastomers. Finlay, J. B.; Hallenbeck, A.; MacLachlan, J. D. (Elastomer Chem. Dep., E. I. du Pont de Nemours and Co., Inc., Wilmington, Del., USA). J. Elastomers Plast., 10(1), 3-16 (English) 1978. CODEN: JEPLAX. ISSN: 0095-2443. DOCUMENT TYPE: Journal CA Section: 38 (Elastomers, Including Natural Rubber) Fluoroelastomer compns. contg. an aliph. peroxide, e.g., 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane [78-63-7], a coagent, i.e. triallyl isocyanurate [1025-15-6], and an acid acceptor are nonscorching but cure rapidly over a range of conventional cure temps. In contrast to conventional curing systems, the peroxide systems give rapid, nonsponging, atm.-pressure cures, with improved properties resulting from oven postcuring, but without the tedious procedures previously needed to avoid fissuring of thick articles. In some cases the post cure was entirely eliminated. Potential applications for the system are discussed.