摘要:
Flame retardant aromatic polycarbonate blends are provided which are capable of being tested V-O under UL-94 test conditions. A triarylsilicon material such as triphenylsilanol is incorporated into the aromatic polycarbonate to provide transparent, flame retardant compression moldable thermo-plastics capable of satisfying the UL-94 V-O requirement at 1/16".
摘要:
A method for hydrogenating olefins and alkynes is provided wherein the unsaturated hydrocarbon is reacted under mild conditions in the presence of a cyclometallated transition metal catalyst which shows greater resistance to degradation caused by oxidation.
摘要:
A current limiting device utilizing an electrically conductive composite material and an inhomogeneous distribution of resistance structure is disclosed. The inhomogeneous distribution is typically chosen so that at least one selected thin layer of the current limiting device has much higher resistance than the rest of the current limiting device. In the actual device, pressure is typically exerted on the composite material in a direction normal to the selected thin layer. During a short-circuit, it is believed that adiabatic resistive heating of this selected thin layer is followed by rapid thermal expansion which leads to either a partial or complete physical separation of the current limiting device at the selected thin layer which produces a higher over-all device resistance to electric current flow. Thus the current limiting device limits the flow of current through the short-circuited current path. When the short-circuit is cleared, the current limiting device regains its low resistance state allowing electrical current to flow normally. The current limiting of the present invention is reusable for many such short circuit conditions.
摘要:
Silicone foams are prepared by microwave curing of a mixture of at least one polyorganosiloxane having vinyl groups attached to silicon; at least one hydride polysiloxane; a blowing agent comprising water and, preferably, at least one monohydroxyaliphatic compound, a cyclodextrin inclusion compound of a platinum group metal coordination complex (preferably with a cyclic diene) and a filler. The use of the inclusion compound as a catalyst increases the shelf life of the composition, whereupon curing and foaming occur together upon exposure to microwave radiation.
摘要:
There is provided an infrared radiation curable organopolysiloxane composition having a poly(alkenylorganosiloxane), a siloxane hydride, an infrared radiation absorbent material, such as carbon black, and an effective amount of a platinum group metal catalyst. The infrared radiation curable organopolysiloxane composition can be used as a binder for a desiccant, such as a zeolite, useful in making multi-panel thermal pane windows.
摘要:
A method is provided for using ultrasonic energy to effect the rapid cure of one-part and two-part curable silicone compositions comprising a vinyl silicone, a silicon hydride siloxane and an effective amount of a platinum group metal catalyst.
摘要:
Methyl silicone resins are pyrolized in a non-oxidizing atmosphere to form a translucent glass comprised of silicon, oxygen and carbon where silicon atoms are chemically bonded to carbon and oxygen atoms, but there are essentially no chemical bonds between carbon and oxygen atoms. The translucent silicon-oxy-carbide glasses of this invention resist devitrification and decomposition in oxidizing or reducing atmospheres at temperatures of about 1250.degree. C. or greater. Methods for forming silicon-oxy-carbide glass articles are disclosed, along with specific methods for forming silicon-oxy-carbide glass fibres, composites, and cellular structures.
摘要:
Shelf stable heat curable mixtures of vinyl substituted organopolysiloxane fluid and siloxane hydride are provided. The one part polyorganosiloxane mixtures are catalyzed with an inclusion compound of a cyclodextrin and a complex of a cyclopentadiene, 1,5-cyclooctadiene or norbornadiene and a platinum group metal material, such as a C.sub.(1-4) alkyl substituted platinum or a rhodium halide.
摘要:
One part heat curable organopolysiloxane compositions are provided which utilize a vinyl containing organopolysiloxane composition, a siloxane hydride, an effective amount of a platinum group metal catalyst and a sufficient amount of an azodicarbonyl compound as an inhibitor which is free of ester linkages.
摘要:
Shelf stable heat curable mixtures of vinyl substituted organopolysiloxane fluid and siloxane hydride are provided. The one part polyorganosiloxane mixtures are catalyzed with an inclusion compound of a cyclodextrin and a complex of a cyclopentadiene, 1,5-cyclooctadiene or norbornadiene and a platinum group metal material, such as a C.sub.(1-4) alkyl substituted platinum or a rhodium halide.