| 摘要 |
PURPOSE:To obtain a rubber composition capable of having increased hardness without reduction of elongation when ruptured after vulcanization and having suppresed calorific value, by compounding a raw material rubber with a cobalt carboxylate, a p-hydroxystyrene polymer and a formaldehyde donor. CONSTITUTION:100pts.wt. Raw-material rubber is compounded with 0.02-0.8 pt.wt. (calculated on cobalt) cobalt carboxylate, 1-10pts.wt. p-hydroxystyrene polymer and 0.1-1.5pts.wt. (per pt.wt. said polymer) formaldehyde donor. The raw material rubber to be used is pref. a rigid one, and in view of suppression of calorific value, a natural or polyisoprene rubber is preferred. Methoxymethylamine, hexamethylenetetramine, etc. are used as the formaldehyde donor. |
