摘要:
The present invention is crosslinked polymer particles, prepared from a free-radical activated reaction of an unsaturated coagent and low molecular weight hydrocarbons or certain polymers. This invention allows particles to be made from mixtures of coagents and saturated compounds. The invention is also a process for preparing crosslinked polymer particles.
摘要:
Polymer compositions comprise a (i) silane-functionalized polymer, e.g., a polyethylene grafted with vinyl triethoxy silane, (H) polyfunctional alcohol e.g., α,α,α′,α′˜tetramethyl-I,3-benzenediethanol and, optionally, (iii) acid, e.g., an alkylated aryl disulfonic acid. The use of polyfunctional alcohols in the absence of a strong acid yields a light-crosslinking of the silane-functionalized polymer and this, in turn, provides a polymer melt with improved extensional properties such as elongational viscosity and melt strength. The use of a polyfunctional alcohol in combination with a blocked strong acid provides a slow rate of crosslinking during melt processing and a high degree of ultimate crosslinking after the polymer composition has been shaped or molded.
摘要:
Polymer compositions comprise a (i) silane-functionalized polymer, e.g., a polyethylene grafted with vinyl triethoxy silane, (H) polyfunctional alcohol e.g., α,α,α′,α′˜tetramethyl-I,3-benzenediethanol and, optionally, (iii) acid, e.g., an alkylated aryl disulfonic acid. The use of polyfunctional alcohols in the absence of a strong acid yields a light-crosslinking of the silane-functionalized polymer and this, in turn, provides a polymer melt with improved extensional properties such as elongational viscosity and melt strength. The use of a polyfunctional alcohol in combination with a blocked strong acid provides a slow rate of crosslinking during melt processing and a high degree of ultimate crosslinking after the polymer composition has been shaped or molded.
摘要:
Ethylene-vinylsilane copolymers are moisture-cured under ambient conditions using a synergistic combination of at least one Lewis acid and at least one Brønsted acid or at least one Lewis base and at least one Brønsted base. Preferably the catalyst system comprises a Lewis acid, e.g., dibutyltin dilaurate, in combination with a Brønsted acid, e.g., sulfonic acid. The Lewis acid or base and the Brønsted acid or base is present in the catalyst system at a molar ratio of Lewis acid/base to Brønsted acid/base of 1:10 to 10:1.
摘要:
The present invention yields a triallyl phosphate (TAP)-mediated, rheology-modified polymer being prepared in a reaction from a reaction mixture made from or containing (a) a free-radical, chain-scissionable organic polymer and (b) TAP, wherein the TAP-mediated, rheology-modified polymer has extensional viscosity at Hencky strains above one greater than that of the free-radical, chain-scissionable organic polymer and/or a Relaxation Spectra Index (RSI) greater than that of the free-radical, chain-scissionable organic polymer.
摘要:
A process for manufacturing a multilayer article, the article comprising two crosslinked semiconductive layers separated by and bonded to an insulation layer, the semiconductive layers formed from a peroxide-crosslinkable olefin elastomer and the insulation layer comprising composition comprising a silane-grafted olefinic elastomer, the process comprises the steps of: (A) injecting the silane-grafted olefinic elastomer between the two crosslinked semiconductive layers so as to have direct contact with each semiconductive layer, and (B) crosslinking the silane-grafted olefinic elastomer in the absence of a peroxide catalyst.
摘要:
A process for manufacturing a multilayer article, the article comprising two crosslinked semiconductive layers separated by and bonded to an insulation layer, the semiconductive layers formed from a peroxide-crosslinkable olefin elastomer and the insulation layer comprising composition comprising a silane-grafted olefinic elastomer, the process comprises the steps of: (A) injecting the silane-grafted olefinic elastomer between the two crosslinked semiconductive layers so as to have direct contact with each semiconductive layer, and (B) crosslinking the silane-grafted olefinic elastomer in the absence of a peroxide catalyst.
摘要:
Compositions comprising: A. Ethylene-based polymer, e.g., LDPE; B. Polyalkylene glycol, e.g., PEG; C. Tertiary hindered amine stabilizer; D. Sulphur-containing hindered phenol antioxidant; E. Peroxide; and F. Optional coagent are useful in the preparation of TRXLPE insulation for medium voltage cable that exhibits a commercially desirable balance of long term heat aging retardancy and water-tree resistance.
摘要:
Crosslinked, melt-shaped articles are manufactured by a process that does not require the use of post-shaping external heat or moisture, the process comprising the steps of: A. Forming a crosslinkable mixture of a 1. Organopolysiloxane containing one or more functional end groups; and 2. Silane-grafted or silane-copolymerized polyolefin; and B. Melt-shaping and partially crosslinking the mixture; and C. Cooling and continuing crosslinking the melt-shaped article. Crosslinking is promoted by the addition of a catalyst to the mixture before or during melt-shaping or to the melt-shaped article.
摘要:
Crosslinked, melt-shaped articles are manufactured by a process that does not require the use of post-shaping external heat or moisture, the process comprising the steps of: A. Forming a crosslinkable mixture of a 1. Organopolysiloxane containing one or more functional end groups; and 2. Silane-grafted or silane-copolymerized polyolefin; and B. Melt-shaping and partially crosslinking the mixture; and C. Cooling and continuing crosslinking the melt-shaped article. Crosslinking is promoted by the addition of a catalyst to the mixture before or during melt-shaping or to the melt-shaped article.