curing for compositions based on polymeric xxxx xxxx xxxx organosilicon compounds and acid fuel substances

摘要

1,227,074. Curable organosilicon resins containing acidic " fillers. DOW CORNING CORP. 25 April, 1969 [27 May, 1968], No. 21176/69. Heading C3T. A curable resin comprises (A) an organosilicon polymer containing at least 0À25 wt. per cent of Si-bonded OH groups and having its Si atoms linked by oxygen atoms or divalent hydrocarbon or halohydrocarbon groups which may contain ether linkages, the remaining Si valences being satisfied by monovalent hydrocarbon or halohydrocarbon, optionally ethercontaining, groups or cyanoalkyl groups, providing at least 0À75 such groups per Si atom, (B), as filler, MoS 2 , ZnS, BN, WS 2 , ZnO, or powdered Ni, Al, Zn, Cu, bronze, or stainless steel, or a mixture thereof, and (C) triethylene diamine or 2-ethyl-4-methyl-imidazole, (C) amounting to 0À1-10 wt. per cent of (A), and (A) to 3-90 wt. per cent of (A) plus (B). Suitable organosilicon polymers are described; preferred are polysiloxanes having methyl, ethyl, isopropyl, vinyl and/or phenyl groups and at least 1 wt. per cent of OH. Other (exemplified) conventional fillers may be used, up to 75% of the total weight of filler, and other conventional curing catalysts, e.g. PbO, PbCO 3 , carboxylic acids and ammonium carboxylates; other resins, e.g. phenolic, epoxy or alkyd resins, or PTFE may also be present. In Examples 1-7 a polysiloxane containing monomethyl- and monophenyl-siloxane units with some phenylmethyl- and diphenyl-siloxane units and 7% OH is milled with MoS 2 and/or ZnS and Ca or Zn stearate and either of the catalysts (C) with or without a diallyl phthalate resin plus dicumyl peroxide, or carnauba wax plus diepoxy dicyclopentadiene plus cyclic succinic-glutaric dianhydride or benzophenone tetracarboxylic dianhydride, or a phenolic resin, or talc. In Example 9, a wide variety of compositions are described using all the specified fillers (B) and catalysts (C), with siloxanes containing methyl, ethyl, isopropyl, octadecyl, phenyl, tolyl, cyanopropyl, methoxypropyl and trifluoropropyl groups and some units -Si(CH 3 )C 6 H 4 OC 6 H 4 Si(CH 3 )O- and -Si(CH 3 ) 2 CH 2 CH 2 CHFCH 2 CH 2 -Si(CH 3 ) 2 -; auxiliary fillers: aerogel SiO 2 , TiO 2 , quartz, diatomaceous earth, Fe 2 O 3 , glass fibres or Fe 2 O 3 ; and organosilicon compounds: 1: 3: 5- tris - (hydroxydimethylsilyl) - benzene, phenylsilanetriol, HOSi (CH 3 ) 2 OSi(CH 3 ) 2 CH 2 CH 2 CH 2 OCH 2 CHFCH 2 Si(CH 3 ) 2 OSi(CH 3 ) 2 OH or 1-trifluoropropoxypropyl - 3: 5 - dimethyl - 1: 3: 5- trihydroxycyclotrisiloxane.