摘要:
The invention relates to branched organopolysiloxanes and to their preparation and use. A branched organopolysiloxane is prepared by the reaction of an alkoxysilane with a substantially linear organopolysiloxane containing at least one hydroxyl or hydrolysable group bonded to silicon, in the presence of a phosphazene catalyst. The branched organopolysiloxanes obtained can be suitable for use in a moisture curable sealant composition capable of curing to a high modulus seal, with less tendency to gel than when using other siloxane polycondensation catalysts. Phosphazene catalysts also have the advantage that the content of undesired low molecular weight cyclic silicones in the polymerisation product is low.
摘要:
Silicone pressure sensitive adhesive (PSA) compositions and methods for their preparation are provided. In one embodiment, PSAs are formed from a silicone polymer mixture by condensation polymerization of low viscosity polyorganosiloxanes in inert solvents and/or silicone fluids, and optionally adding a silicone resin (MQ) during polymerization. The silicone polymer mixture formed may also be mixed with a silicone resin (MQ) and bodying catalyst, and bodying is allowed to continue until the desired reaction product is formed.
摘要:
A release coating composition according to the present invention comprises an alkenyl functional polysiloxane (1), a silicon hydride functional polysiloxane (11) and a catalyst (111) comprising a platinum group metal. The alkenyl functional polysiloxane (1) is an alkenylterminated polysiloxane prepared by siloxane polycondensation and/or equilibration using a phosphazene base catalyst followed by neutralisation with an acidic neutralising agent. The level of catalyst (III) in the composition can be as low as 2-40 parts per million platinum group metal by weight.
摘要:
This invention relates to silicone coating composition comprising a solventless silicone coating composition and a liquid silicone mist suppressant composition obtained by a method comprising reacting a large excess of at least one organohydrogensilicon compound containing at least three silicon-bonded hydrogen groups with at least one compound containing at least two alkenyl groups in the presence of a platinum group metal-containing catalyst.
摘要:
The invention relates to branched organopolysiloxanes and to their preparation and use. A branched organopolysiloxane is prepared by the reaction of an alkoxysilane with a substantially linear organopolysiloxane containing at least one hydroxyl or hydrolysable group bonded to silicon, in the presence of a phosphazene catalyst. The branched organopolysiloxanes obtained can be suitable for use in a moisture curable sealant composition capable of curing to a high modulus seal, with less tendency to gel than when using other siloxane polycondensation catalysts. Phosphazene catalysts also have the advantage that the content of undesired low molecular weight cyclic silicones in the polymerization product is low.
摘要:
Silicone-based pressure-sensitive adhesive composition comprising 100 parts (A) a branched organopolysiloxane having on molecular terminals at least two alkenyl groups and represented by (R3SiO1/2)4-p(R1R2SiO1/2)p(R2SiO)m(RR1SiO)n(SiO4/2), to 400 parts (B) an organopolysiloxane composed of R3R22SiO1/2 units and SiO4/2 units, (C) an organohydrogenpolysiloxane, and a catalytic quantity of (D) a platinum-type catalyst. Pressure-sensitive adhesive tape or sheet having an adhesive layer in the form of a cured layer of the aforementioned composition.
摘要:
Silicone-based pressure-sensitive adhesive composition comprising 100 parts (A) a branched organopolysiloxane having on molecular terminals at least two alkenyl groups and represented by (R3SiO1/2)4-p(R1R2SiO1/2)p(R2,SiO)m(RR1SiO)n(SiO4/2), to 400 parts (B) an organopolysiloxane composed of R3R2SiO1/2 units and SiO4/2 units, (C) an organohydrogenpolysiloxane, and a catalytic quantity of (D) a platinum-type catalyst. Pressure-sensitive adhesive tape or sheet having an adhesive layer in the form of a cured layer of the aforementioned composition.
摘要:
Air bags which are used for safety purposes to protect occupants of vehicles such as automobiles are described together with a process for coating air bags and air bag fabrics with silicone rubber compositions. In particular the invention relates to silicone rubber coatings which cure by hydrosilylation and an air bag coated with an elastomeric coating which is the cured product of a silicone composition comprising an organopolysiloxane (A) having aliphatically unsaturated hydrocarbon or hydrocarbonoxy substituents, an organosilicon crosslinker having at least 3 silicon-bonded hydrogen atoms, a catalyst able to promote the reaction of the aliphatically unsaturated hydrocarbon or hydrocarbonoxy substituents with Si—H groups and a reinforcing filler, wherein the organopolysiloxane (A) comprises a branched organopolysiloxane (A1) consisting of: (i) one or more Q units of the formula (SiO4/2) and (ii) from 15 to 8000 D units of the formula Rb2SiO2/2 which units (i) and (ii) may be inter-linked in any appropriate combination, and (i{umlaut over (υ)}) M units of the formula RaRb2SiO1/2 wherein each Ra substituent is selected from the group consisting of an alkyl group having from 1 to 6 carbon atoms, an alkenyl group having from 1 to 6 carbon atoms and an alkynyl group having from 1 to 6 carbon atoms, at least three Ra substituents in the branched siloxane being alkenyl or alkynyl units, and each Rb substituent is selected from the group consisting of an alkyl group having from 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an aryl group, an alkoxy group, an acrylate group and a methacrylate group.
摘要翻译:用于安全目的来保护诸如汽车的车辆的乘客的气囊与用硅橡胶组合物涂覆气囊和气囊织物的方法一起描述。 特别地,本发明涉及通过氢化硅烷化固化的硅橡胶涂层和涂覆有弹性体涂层的气囊,其是包含具有脂族不饱和烃或烃氧基取代基的有机聚硅氧烷(A)的有机硅组合物的固化产物,有机硅交联剂具有 至少3个硅键合的氢原子,能够促进脂族不饱和烃或烃氧基取代基与Si-H基团和增强填料反应的催化剂,其中有机聚硅氧烷(A)包含支化有机聚硅氧烷(A1) i)一个或多个式(SiO 4/2)的Q单元和(ii)式R b 2 SiO 2/2的15至8000D单元,其中单元(i)和(ii)可以任何适当的组合相互连接, 和(i(umlaut over(υ)})式R a R b 2 SiO 1/2的M单元,其中每个R a取代基选自具有1至6个碳的烷基 具有1至6个碳原子的烯基和具有1至6个碳原子的炔基,至少3个支链硅氧烷中的Ra取代基为烯基或炔基单元,并且每个Rb取代基选自 具有1至6个碳原子的烷基,具有2至6个碳原子的烯基,芳基,烷氧基,丙烯酸酯基和甲基丙烯酸酯基。
摘要:
A solventless cured release coating-forming organopolysiloxane composition having a viscosity at 25° C. of 50 to 2,000 mPa·s comprising (A) 100 weight parts of an alkenyl-functional diorganopolysiloxane that has a viscosity of 25 to 1,000 mPa·s; (B) 0.5 to 15 weight parts of a diorganopolysiloxane that has a viscosity of at least 10,000 mPa·s and that has an aliphatically unsaturated group content of no more than 0.1 mole %; (C) 0.5 to 5 weight parts of a branched organopolysiloxane that has more than one SiO4/2 unit and that is a polymer product provided by an equilibration polymerization between a branched organosiloxane oligomer represented by the average siloxane unit formula (1) (SiO4/2)(RaRb2SiO1/2)x(1) and a diorganosiloxane oligomer; (D) a specific amount of an organohydrogenpolysiloxane that has a viscosity of 1 to 1,000 mPa·s; and (E) a hydrosilylation reaction catalyst in a catalytic quantity.
摘要:
This invention relates to silicone coating composition comprising a solventless silicone coating composition and a liquid silicone mist suppressant composition obtained by a method comprising reacting a large excess of at least one organohydrogensilicon compound containing at least three silicon-bonded hydrogen groups with at least one compound containing at least two alkenyl groups in the presence of a platinum group metal-containing catalyst.