| 摘要 |
PROBLEM TO BE SOLVED: To stably obtain a phenolic resin composition capable of giving cured products with excellent thermal characteristics and impact resistance by controlling the respective contents of water and a phenolic compound in a mixture comprising a phenolic resin, a specific organopolysiloxane and an emulsifier to a specified proportion followed by carrying out a crosslinking reaction. SOLUTION: This resin composition is obtained by controlling the water content ((a) wt.%, (a)<=5) and the phenolic hydroxyl-contg. compound content (b wt.%, b<=20) of a mixture comprising (A) a heated and melted phenolic hydroxyl-contg. resin (e.g. novolak resin), (B) an organopolysiloxane having respective silanol groups on both ends and (C) an emulsifier (pref. a modified silicone oil) so as to satisfy the formula 17a+b>=5 followed by addition of (D) a crosslinking agent for silanol condensation reaction (pref. a polyfunctional silane compound) and (E) a catalyst for the silanol condensation reaction (pref. an organotin compound) to carry out a crosslinking reaction, and then removing water after ending the reaction.
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