摘要:
Use of OO-t-amyl-O(2-ethylhexyl)monoperoxycarbonate as a curing catalyst for bulk molding compounds (“BMC”s) and sheet molding compounds (“SMC”s) is provided.
摘要:
The melt of polyvinyl aromatic polymers comprising from 10 to 45 weight % of star branched polymer prepared using a combination of thermal and tetra functional peroxide initiation has an improved melt strength permitting better foam formation for extrusion foam blown with conventional blowing agents and inert gases including CO2 and an improved tensile strength for oriented polystyrene (OPS) articles, e.g. blown film or extruded sheet.
摘要:
Adhesive composition, including a mixture of about 1 percent to about 35 percent by weight of chlorinated polymer, about 1 percent to about 35 percent by weight of a nitrile elastomer, a rubber-modified acrylonitrile copolymer, or mixtures thereof, and about 25 percent to about 90 percent by weight of an alkyl acrylate or methacrylate monomer.
摘要:
A sulfur vulcanizing system rubber composition comprises EPDM, zinc as a vulcanization accelerator activator, at least one thiazole type vulcanization accelerator serving to control the dissolution of zinc from the composition, and at least one ultra-accelerator of the thiuram or dithiocarbamate type, these accelerators being preferably combined under specified quantitative limitations. The hose using this rubber composition is particularly suitable for use in a cooling system for an automobile engine, since the dissolution of zinc into a coolant is prevented, thereby preventing the formation of any zinc compound causing the blocking of the hose, or the leakage of the coolant through the seal between the hose and any pipe connected therewith.
摘要:
In the present invention, particles of an ethylene-vinyl alcohol copolymer (EVOH) are contacted with a solution containing a boron compound, whereby to obtain a substantially homogeneous distribution of the boron compound within the particles. For example, EVOH and the solution are continuously fed into a treatment apparatus and brought into contact with each other in the treatment apparatus, and the EVOH when continuously removed from the apparatus is in contact with the solution containing the boron compound in a concentration of at least 0.7 times but not more than 1.3 times a solution equilibrium concentration.
摘要:
Blends of syndiotactic 1,2-polybutadiene and rubbery elastomers are prepared by a process that comprises polymerizing 1,3-butadiene monomer into syndiotactic 1,2-polybutadiene within a rubber cement of at least one rubbery elastomer by using a chromium-based or molybdenum-based catalyst composition.
摘要:
Molecular weight modification of polypropylene by 4-(t-amylperoxy)-4-methyl-2-pentanol and polypropylene so modified suitable for handling and packaging food, beverages and pharmaceuticals and for use in medical devices is disclosed.
摘要:
The invention provides a resin composition comprising a crosslinking silyl-terminated stellar-structure vinyl polymer or a stellar-structure vinyl block copolymer or chain-extended vinyl block copolymer. The invention provides a method of producing a stellar-structure vinyl block copolymer or chain-extended vinyl block copolymer which comprises forming a block copolymer using living radical polymerization and adding a compound having two or more polymerizable carbon-carbon double bonds at the end point of polymerization of the block copolymer.
摘要:
Novel polymer compositions for controlling or correcting dispersion mismatch between the composition and a side-fiber polished optical fiber are disclosed. The polymer compositions contain an infrared absorbing dye having an absorption maximum from about 900 to about 1200 nm and and a polar olefin copolymer containing monomers which are formed from polar olefins having an ester, benzene, or halogen substitutent attached. A method for controlling the dispersion exhibited by the novel polymer compositions is also disclosed. The method includes forming the polymer composition over an exposed surface of an optical fiber. Dispersion is controlled by controlling the amount of dye present in the polymer composition. Also disclosed is an optical device from which improvements in the uniformity of spectral response and performance are observed across a wavelength band. The optical device includes the polymer composition formed over an optical fiber. Variable optical attenuators, switches, and couplers can be designed which incorporate the polymer compositions. The invention is particularly useful in the 1500-1600 nm wavelength band.
摘要:
A peroxide cure system rubber composition comprises EPDM having a high iodine value and an appropriate ethylene proportion, and preferably at least quinoline as an antioxidant, and is particularly suitable for use in making a hose in a cooling system for an automobile engine. The hose is highly resistant to hot air aging and cracking, though the composition does not contain zinc.