Polyethylene, crosslinking

Tang CY, Xie XL, Wu XC, Li RK, Mai YW (2002). Enhanced wear performance of ultra high molecular weight polyethylene crosslinked by organosilane. J. Mater. Sci. Mater. Med. 13 1065-1069. 

Within the family of polyolefins there are many individual families that include low density polyethylenes, linear low density polyethylenes, very low polyethylenes, ultra low polyethylenes, high molecular weight polyethylenes, ultra high molecular weight polyethylenes, polyethylene terephthalates, ethylene-vinyl acetate polyethylenes, chlorinated polyethylenes, crosslinked polyethylenes, polypropylenes, polybutylenes, polyisobutylene, ionomers, polymethylpentene, thermoplastic polyolefin elastomers (polyolefin elastomers, TP), and many others. 

The photocrosslinking of polyethylene has attracted some considerable interest. The properties of high density polyethylene crosslinked with triallyl cyanurate have been examined217,218 while... 

Fhe sequence of these two reaction steps is repeated many times even at initial concentrations of Co ions which are 1000 times lower than that which corresponds to a molar concentration of hydroperoxide. As the above reaction cycles of hydroperoxide decomposition yield only one radical per one molecule of peroxide decomposed, the efficiency of polyethylene crosslinking should be accordingly lower than that of thermally initiated peroxide decomposition. The yield of free radicals should be moreover reduced by other side reactions. The amount of insoluble gel obtained in such a way does not exceed 40 %. (The efficiency of crosslinking reaction may, however, be, increased by a parallel use of polyfunctional monomers.)... 

Such a procedure of polyethylene crosslinking is suitable for thin products, as e.g. for foils of thickness 0.1 mm where the time of crosslinking of LDPE is about 1 h at 70 "C. To obtain more than 80% of gel, 2.5% w. of cumyl hydrt eroxide, 2% w. of glycol dimethacrylate and 0.1 % w. of Co(II) naphthenate should be used. 

The group of azoesters considered as initiators of polyethylene crosslinking includes commercially available 2,2 azobis (2-acetoxy propane) and 2,2 azobis (2-acet-oxybutane). Primary homolysis of 2,2 azobis (2-acetoxypropane)... 

Thermoset, those that cannot be resoftened, including polyethylene (crosslinked), phenolics, and alkyds like the polyesters (polymers based on maleic, terephthalic, or other carboxylic acids and glycol, propylene glycol or similar alcohols). 

Kang, P.H., Nho, Y.C., April 2001. Characteristics of heat shrinkable high density polyethylene crosslinked by y-irradiation. Journal of the Korean Nuclear Society 33 (2). 

As a result of this extensive experimental program, it has been found that in rotational molding, polyethylene and polypropylene polymers show different degradation behavior. While in polypropylene the thermo-oxidative degradation causes mainly chain scission, in polyethylene crosslinking dominates. The use of increased amounts of antioxidant in the... 

Szymczak and Manson, 1974a,b White and Mann, 1967). As with electron-irradiated polyethylene, crosslinked poly(vinyl chloride) formulations (usually plasticized) are now of commercial interest as wire and cable coatings and insulation [see, for example, Nicholl (1969)]. In the following sections, typical properties will be described and discussed details of other standard polymer-monomer graft polymerizations are given by, e.g., Chapiro (1962) and Charlesby (1960). 

Crossential SA-14. See Vipers bugloss (Echium plantagineum) oil Crosslink PS 505. See Polyethylene Crosslink WA 405. See Dodecylbenzenesulfonic acid Crosslinked carboxymethyl cellulose Crosslinked cellulose gum Crosslinked CMC Crosslinked NaCMC. See Croscarmellose sodium... 

Uses Catalyst in polyethylene crosslinking, styrene polymerization, polyester resins crosslinking agent for plastics, rubber rheology and processing aid for PP initiator in prod, of propylene homopolymer for use in food pkg. 

Poly (ethylene-co-propylene). See EPM rubber Poly (ethylene-co-propylene-co-5-methylene-2-norbornene). See Ethylene-propylene-ethylidene norbornene Poly (ethylene-co-tetrafluoroethylene). See Ethylene/tetrafluoroethylene copolymer Poly (ethylene-co-vinyl acetate). See Ethylene/VA copolymer Polyethylene, crosslinked Synonyms XLPE XPE... 

Xincure ITX-2. See 2-Isopropyl thioxanthone Xincure MBP. See 4-Methoxybenzophenone Xincure MBZ. See 4-Methylbenzophenone Xincure PBZ. See p-Phenylbenzophenone Xincure TMBZ. See 2,4,6-T ri methyl benzophenone Xinsorb BP-4. See Benzophenone-4 Xinsorb UV-1. See Ethoxycarbonylphenyl)-N -methyl-N -phenylformamidine Xinsorb UV-9. See Benzophenone-3 Xinsorb UV-A. See Acetanisole Xinsorb UV-P. See Drometrizole X-Link 2833, X-Link 2893, X-Link 5627. See Vinyl acrylic copolymer XLPE. See Polyethylene, crosslinked XO White. See Calcium monocarbonate XP-36P. See Sodium hexametaphosphate X-Pand R . See Food starch, modified XPE. See Polyethylene, crosslinked XPS. See Polystyrene, expandable XSA 80, XSA 90, XSA 95, XSA. See Xylene sulfonic acid... 

Benzotrifluoride o-Chlorobenzotrifluoride p-Chlorobenzotrifluoride Dichlorotetrafluoroethane 1,2-Dichlorotetrafluoroethane Dimethicone Propionitrile Tetra-n-butoxysilane 1,2,3,4-Tetrachlorobenzene Tetrakis (2-ethylbutoxy) silane Tetrakis (2-ethylhexoxy) silane 1,3,5-Trichlorobenzene dielectric fluid, switch gears PerfIuorodecalin PerfIuoromethyldecalin dielectric fluid, transformers PerfI uorodecal i n PerfI uoromethyl decal i n dielectric gas Chloropentafluoroethane dielectric insulator, high-voltage cables Polyethylene, crosslinked dielectric layers in electronic circuits Tantalum oxide dielectric liquid Di butyl sebacate dielectric oils Silicone dielectrics... 

Sodium nonoxynol-6 phosphate floor heating piping, domestic Polyethylene, crosslinked floor insulation Perlite... 

Polyethylene, crosslinked foam, vehicle sound insulation Polyethylene, crosslinked foambuilder, cosmetics Octoxynol-15... 

Matty polymers may be used for produetion of wire and cable. These include polyethylene, crosslinked polyethylene, chlorosnlfonated polyethylene, ethylene-propylene rubber, polyvinylchloride, bntyl robber, styrene bntadiene rubber, silicone rubber, natural robber, polyisoprene robber, polyurethane, nitrile butadiene rubber, polychloroprene, polysulfone, thermoplastie elastomers, polyimide, and polyamides. Selection of polymer(s) depends on projected conditions of service such as temperature, presence of corrosive liquids, surrounding temperature, quality of insulation, etc. 

Peroxide degrades some plastics, such as polypropylene (PP). Consequently, in peroxide crosslinked TPVs, polymers like PP degrade and polymers like polyethylene crosslink. In phenolic resin cured TPVs, thermoplastics like PP do not degrade but moisture is always an issue, because the stannous chloride or zinc chloride that are used as Lewis acid are hygroscopic. 

Peroxyketals Polyethylene crosslinking Unsaturated polyester curing... 

Which of these two principal types is the better is not clear-cut. The plastics insulation is relatively easy to apply by cross-head extrusion. PVC, polyethylene, crosslinked polyethylene, ethylene propylene rubbers are commonly used. This is a relatively cheap and efficient process. Paper cable manufacture, by comparison, is a complex and labour-intensive... 

Properties Mediimi Density Polyethylene Polyethylene Crosslinked Compounds, Molding Grades... 

Creep rupture test 50,201, 208 Critical deformation 213 Crosslinked polyethylene, see Polyethylene Crosslinking 43... 

Ciuprina, F., Teissedre, G., Fifippini, J.C. Polyethylene crosslinking and water treeing. 

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