초록 ▼

Curable organosilicone resin coating compositions are disclosed wherein part or all of the solvent ordinarily present in conjunction with a conventional hydroxyl functional organosiloxane resin copolymer is replaced with a reactive liquid silicone resin having an increased flash point and reduced vo

Curable organosilicone resin coating compositions are disclosed wherein part or all of the solvent ordinarily present in conjunction with a conventional hydroxyl functional organosiloxane resin copolymer is replaced with a reactive liquid silicone resin having an increased flash point and reduced volatility relative to a prior art reactive diluent. The liquid silicone resin employed is a reaction product prepared by hydrolyzing, and the neutralizing, an equilibrated mixture of (i) a phenylsilane and (ii) a polydimethylsiloxane, the equilibration reaction being facilitated by a perfluoroalkane sulfonic acid (iii).

대표청구항 ▼

A composition comprising: (A) 100 parts by weight of a hydroxyl functional organosiloxane resin copolymer comprised of at least two units selected from the group consisting of MeSiO3/2 units, Me2SiO2/2 units. PhMeSiO2/2 units. PhSiO3/2 units, Ph2SiO2/2 units and PrSiO3/2 units, in which Me denotes a

A composition comprising: (A) 100 parts by weight of a hydroxyl functional organosiloxane resin copolymer comprised of at least two units selected from the group consisting of MeSiO3/2 units, Me2SiO2/2 units. PhMeSiO2/2 units. PhSiO3/2 units, Ph2SiO2/2 units and PrSiO3/2 units, in which Me denotes a methyl radical, Ph denotes a phenyl radical and Pr denotes a propyl radical, said resin copolymer having 0.5 to 6 weight percent residual hydroxyl radicals attached to the silicon atoms thereof, a total molar organic group to silicon ratio of 1 to 1.7 and a total molar phenyl group to silicon ratio of 0.35 to 0.85; and (B) from about 1 to 100 parts by weight of a liquid silicone resin composition prepared by a process comprising (I) reacting a mixture consisting essentially of (i) a phenylsilane having the general formula PhSi(OR)3 wherein R is selected from the group consisting of methyl, ethyl, propyl and acetyl radicals and Ph denotes a phenyl radical, (ii) a polydimethylsiloxane and (iii) an equilibrating amount of an acid catalyst having the formula ZSO3H wherein Z is a perfluoroalkyl group having 1 to 10 carbon atoms, molar ratio of said polydimethylsiloxane (ii) to said phenylsilane (i) being between about 1:9 and about 9:1, (II) hydrolyzing the reaction product formed in step (I) with sufficient water to provide from about 0.5 to about 1 mole of residual－OR functionality per 100 parts by weight of said liquid silicone resin and (III) neutralizing said acid catalyst (iii).