摘要 |
The mfr. of nitrosamine-free silicone articles comprises (a) mixing (A) a vinyl-contg. organopolysiloxane with (C) a filler, (b) adding an effective amt. of acid soln. to the mixt. to eliminate nitrosamine, (c) adding (B) a silicon hydride siloxane or silicone hydride siloxane fluid and (D) a catalytic amt. of hydrosilation catalyst to the mixt. and heating the resulting mixt. at 50-100[deg]C for 0.5-2.0 hrs; (d) curing the mixt.; and (e) post baking the cured mixt. Pref. the mixt. is heated at 55-90 (60-85)[deg]C for 0.6-1.5 (1) hr. The mixt. is cured in a heated mould. Step (c) further comprises adding an effective amt. of a catalyst inhibitor. The acid comprises HCl, HBr, HI, sulphuric acid, formic acid, acetic acid or phosphoric acid. |