| 摘要 |
Phenolic siloxane compositions are prepared in a first embodiment by combining phenol with an aldehyde and an alkoxy or silanol-functional silicone intermediate; in a second embodiment by combining a phenolic novolac resin with a formaldehyde donor and an alkoxy or silanol-functional silicone intermediate; and in a third embodiment by combining a phenolic resole resin with an alkoxy or silanol-functional silicone intermediate. Optionally, a catalyst to facilitate formation of a phenolic resin from phenol and formaldehyde can be added, a catalyst to facilitate condensation of the phenolic resin can be added, and at least one catalyst to facilitate hydrolysis and/or condensation of the silicone intermediate can be added. The phenolic resin catalyst can include acids, bases, and formaldehyde donors. The silicone intermediate catalyst can include organometallic compounds, amine compounds, and mixtures thereof. The ingredients react to form a phenolic siloxane composition comprising an IPN of siloxane and phenolic polymers, and having siloxane groups in the phenolic polymer. The phenolic siloxane composition has flame, heat and chemical resistance equal to or exceeding conventional phenolic resins, and has improved properties of impact resistance, tensile strength, flexural modulus, and density when compared to conventional non-siloxane phenolic siloxane compositions.
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