| 摘要 |
PURPOSE:To obtain the title composition excellent in mechanical strengths, cracking resistance, heat shock resistance and heat deterioration resistance, by mixing a phenolic OH group-containing resin with a silanol group-terminated organopolysiloxane and a crosslinking agent for silanol condensation. CONSTITUTION:A phenolic resin composition comprising 100pts.wt. phenolic OH group-containing resin (e.g., novolac phenolic resin), 3-50pts.wt. silanol group-terminated organopolysiloxane of formula I (wherein n>=10 and R is a monovalent hydrocarbon group), e.g., one having a methyl group as R and an OH group equivalent of 5,000 and 0.05-5pts.wt. crosslinking agent for silanol condensation, e.g., methylhydrogenpolysiloxane of formula II (wherein n>=3). When this composition is used for a molding material or a friction material, it is excellent in mechanical strengths, cracking resistance and heat shock resistance, low in deterioration in a coefficient of friction and low in abrasion, etc. Therefore, it can find various application fields as a phenol resin, such as a laminating material, a binder for shell molds and grinding stones, a casting material or a foam material. |
