5838 results about "Addition reaction" patented technology

The invention relates to a process for the preparation of polyorganosiloxanes and polyorganosilanes of high purity by an addition reaction of siloxanes and / or silanes which contain at least one H—Si group with compounds having olefinic double bonds in the presence of a platinum catalyst and optionally further additional components, wherein the reaction is carried out in the presence of a platinum(0) complex catalyst which was dissolved in a solvent before addition to the reaction medium and to whose solution an effective amount of at least one unsaturated hydrocarbon having 2 to 6 carbon atoms was added.

Provided is a heat conductive silicone grease composition, including: an organopolysiloxane containing 2 or more alkenyl groups bonded to silicon atoms within each molecule, an organopolysiloxane with a specific structure and with a kinematic viscosity at 25 DEG C of 10 to 10,000 mm 2 / s, an alkoxysilane containing specific substituent groups, an organohydrogenpolysiloxane containing 2 or more SiH groups within each molecule, a heat conductive filler, a platinum-based catalyst, and an addition reaction retarder. The heat conductive silicone grease composition exhibits high thermal conductivity, has excellent fluidity prior to curing and therefore exhibits favorable workability, is capable of filling fine indentations and therefore reduces contact resistance, and is also able to prevent oil separation and bleeding of the heat conductive material following curing, meaning the composition exhibits excellent heat radiation performance and reliability. Also, the heat conductive silicone grease composition exhibits improved durability under conditions of high temperature and high humidity, and thereby exhibits further improved reliability during actual use.

The crosslinkable rubber composition of the invention is crosslinkable by hot air, and a hot-air crosslinked rubber sheet thereof has no scratch on the surface in a hardness test using a pencil of HB and has a compression set of not more than 70% after a heat treatment at 150° C. for 22 hours. The rubber composition comprises an ethylene / α-olefin / non-conjugated polyene random copolymer rubber comprising a specific vinyl end group-containing norbornene compound, a SiH group-containing compound having at least two SiH groups in one molecule, and if necessary, an addition reaction catalyst comprising a platinum group element and a reaction inhibitor. The automobile weatherstrip, hose, rubber vibration insulator, belt, sealing material, expanded product, covered electric wire, electric wire joint, electric insulating part and household rubber product according to the invention comprise the above-mentioned rubber composition. The rubber composition has a high crosslinking rate and excellent productivity to produce crosslinked rubber molded products, is capable of undergoing hot-air crosslinking such as HAV or UHF and is capable of providing crosslinked rubber molded products having excellent compression set resistance, strength properties, heat resistance, weathering resistance and abrasion resistance.