摘要:
The organopolysiloxane composition is useful as a potting or encapsulating material having a gel-like consistency for protecting electronic components even at an extremely low temperature as is encountered in the space industry. The composition is basically of the type in which crosslinks are formed by the addition reaction between silicon-bonded vinyl groups in an organopolysiloxane and silicon-bonded hydrogen atoms in an organohydrogenpolysiloxane but the outstanding cold resistance of the gel-like material obtained from the composition is imparted by incorporating specific silethylene-containing units of the unit formula OSiMe--CH.sub.2 CH.sub.2 --SiMe.sub.2 O.sub.0.5 into the organopolysiloxane in a specified molar content.
摘要翻译:有机聚硅氧烷组合物可用作具有凝胶状稠度的灌封或封装材料,即使在空间工业中遇到的极低温下也能保护电子元件。 组合物基本上是通过有机聚硅氧烷中与硅键合的乙烯基与有机氢聚硅氧烷中与硅键合的氢原子之间的加成反应形成交联的类型,但由组合物获得的凝胶状材料的出色的耐寒性为 通过将单元式OSiMe-CH 2 CH 2 -SiMe 2 O 0.5的特定的含有亚乙烯基的单元以特定的摩尔含量加入有机聚硅氧烷中。
摘要:
The present fluorosilicone composition is an addition reaction curable composition that uses, as an alkenyl group-containing organopolysiloxane, a fluorine-containing organopolysiloxane represented by the following general formula (1): ##STR1## wherein R represents a vinyl group, R.sup.1 represents an alkyl group or a phenyl group, R.sup.2 represents a group represented by the following formula (2): ##STR2## in which p is an integer of 2 to 8 and q is an integer of 1 to 10, and n and m are each a positive integer. This composition can form a gellike cured product particularly excellent in acid resistance.
摘要:
Curable or vulcanizable fluorinated silicone compositions which comprise a uniform mixture of predetermined amounts of an organopolysiloxane of the following average unit formula ##STR1## in which R.sup.1 represents a monovalent hydrocarbon group having from 1 to 8 carbon atoms, and a and b are, respectively, a defined value; an organohydrogenpolysiloxane having at least three SiH groups in one molecule and consisting of the several siloxane units; and a catalytic amount of a platinum compound. If necessary, another type of polysiloxane may be added to the above composition in order to further improve physical properties. The composition is rapidly vulcanized to give a cured product having stable physical properties within a short time.
摘要:
The invention provides an efficient method for improving the adhesive bonding strength of various types of rubbery sealant compositions, e.g. room temperature curable silicone rubber composition, to the substrate surface on which it has been cured. The method comprises coating the substrate surface with or admixing the sealant composition before application to the substrate surface with an adhesion promotor which is a reaction product of a reaction mixture comprising:(a) 1 mole of an organic amine compound having at least one active hydrogen atom in a molecule or an aminoalkyl alkoxysilane compound;(b) from 0.5 to 4 moles of an organic compound having at least one epoxy group in a molecule or an epoxyalkyl alkoxysilane; and(c) from 0.5 to 12 moles of an alkoxysilane represented by the general formula R.sup.1.sub.a Si(OR.sup.2).sub.4-a, in which R.sup.1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 4 carbon atoms, R.sup.2 is a monovalent hydrocarbon group having 1 to 4 carbon atoms or an alkoxy-substituted alkyl group and a is a number of zero, 1, 2 or 3, or a partial hydrolysis product thereof, at least one of the components (a) and (b) being an aminoalkyl alkoxysilane or an epoxyalkyl alkoxysilane, respectively.
摘要:
An oligomer or a mixture of organopolysiloxane oligomers is polymerized in the presence of a strong acid, e.g. trifluoromethane sulfonic acid, as the catalyst to give an organopolysiloxane containing a considerable amount of silanolic hydroxy groups at the molecular chain ends. Thereafter, the mixture is admixed with water and a hexaorganodisilazane or triorganosilyl amine compound in combination so as to neutralize the acid catalyst by the ammonia produced by the hydrolysis of the disilazane or silyl amine compound with simultaneous silylation of the terminal hydroxy groups. Thus, the organopolysiloxane contains a greatly decreased amount of the residual silanolic hydroxy groups at the molecular chain ends to be imparted with remarkably improved heat stability.
摘要:
A method for concentration of fine particles dispersed in a dispersion into an ionic liquid comprising, adding an ionic liquid, especially an organic ionic liquid at ordinary temperature, e.g., a salt of 1-butyl-3-methylimidazolium with PF6− to a dilute dispersion of fine particles so as to concentrate the fine particles into the ionic liquid.
摘要:
A system for processing supercritical and subcritical fluid capable of bringing the inside of at least one processing container (1) formed in a flow passage into a supercritical or subcritical high pressure field, wherein thermal operation is applied to process fluid to apply thermal expansion to the fluid to produce a pressure difference between the processing container (1) and the outside, whereby a specified temperature and the high pressure field suitable for the processing of the supercritical or subcritical fluid can be provided in the processing container (1).
摘要:
Novel fluorinated unsaturated glycidyl ethers are prepared by reacting 1,1,1-trifluoro-2-trifluoromethyl-3-buten-2-ol or 1,1,1-trifluoro-2-trifluoromethyl-4-propen-2-ol with chloromethyloxirane in the presence of onium salts. The fluorinated unsaturated glycidyl ethers are, in turn, subject to addition reaction with hydrosilanes in the presence of transition metal catalysts, obtaining novel silicon-modified glycidyl ethers or fluorinated organic silicon compounds.
摘要:
Novel siloxane compounds containing a SiH group, an alkoxy or epoxy group-containing organic group attached to a silicon atom, and a perfluoropolyether group-containing organic group, each at least one per molecule, are useful tackifiers for imparting good adhesion to various resins and even fluorinated silicone resins.
摘要:
An organopolysiloxane composition comprising an organopolysiloxane and compounded therein a silica fine powder treated with a silazane compound containing a group represented by the following formula: ##STR1## wherein Rf represents a fluorine-containing organic group; R.sup.2 represents a monovalent hydrocarbon group containing no fluorine atom; R.sup.3 represents a divalent hydrocarbon group; and c is an integer of 0, 1 or 2. The composition has superior release properties and transparency.