Abstract:
The use of magnesium oxide for increasing the rate of crosslinking and/or the crosslinking density of at least one crosslinkable polymer is described in addition to a composition that can be employed in this use, comprising: from 30 to 80% by weight of a crosslinking co-agent, from 0.5 to 10% by weight of an organic peroxide, from 15 to 60% by weight of magnesium oxide, and from 0 to 40% by weight of one or more crosslinkable polymers. An article obtained from this composition is also described.
Abstract:
A primer mixture intended for crosslinking polyethylene, including at least an initiator of free radicals chosen from organic peroxides, azo compounds or mixtures thereof, wherein the mixture has said free-radical initiator and at least one crosslinking promoter chosen from the cycloalkanes having 5 to 7 carbon atoms, substituted by 1 to 3 vinyl, allyl or isopropenyl groups, the aromatic compounds substituted by 1 to 3 vinyl, allyl or isopropenyl groups, the methacrylate, acrylate and maleimide monomers being multi-substituted, and in that the weight ratio of free-radical initiator to the crosslinking promoter is greater than or equal to 1, and preferably between 1.5 and 4. Also, a method and to a use related to this primer mixture.
Abstract:
A primer mixture intended for crosslinking polyethylene, including at least an initiator of free radicals chosen from organic peroxides, azo compounds or mixtures thereof, wherein the mixture has said free-radical initiator and at least one crosslinking promoter chosen from the cycloalkanes having 5 to 7 carbon atoms, substituted by 1 to 3 vinyl, allyl or isopropenyl groups, the aromatic compounds substituted by 1 to 3 vinyl, allyl or isopropenyl groups, the methacrylate, acrylate and maleimide monomers being multi-substituted, and in that the weight ratio of free-radical initiator to the crosslinking promoter is greater than or equal to 1, and preferably between 1.5 and 4. Also, a method and to a use related to this primer mixture.
Abstract:
The use of peroxide(s) for cross-linking at least one polymer, the polymer having a homopolymer or copolymer of ethylene and especially the ethylene-vinyl acetate copolymer (EVA) or a mixture of the EVA with another homopolymer or copolymer of ethylene, and at least one peroxide, wherein the peroxide includes OO-tert-butyl O-isopropyl monoperoxycarbonate or OO-tert-amyl O-isopropyl monoperoxycarbonate and OO-tert-butyl-O-2-ethyl hexyl monoperoxycarbonate or OO-tert-amyl-O-2ethyl hexyl monoperoxycarbonate. Also, a cross-linkable composition including the peroxide and to a method for producing a cross-linked polymer as a result of the peroxide.
Abstract:
The use of magnesium oxide for increasing the rate of crosslinking and/or the crosslinking density of at least one crosslinkable polymer is described in addition to a composition that can be employed in this use, comprising: from 30 to 80% by weight of a crosslinking co-agent, from 0.5 to 10% by weight of an organic peroxide, from 15 to 60% by weight of magnesium oxide, and from 0 to 40% by weight of one or more crosslinkable polymers. An article obtained from this composition is also described.
Abstract:
A masterbatch including an ethylene copolymer and at least one ethylene comonomer having at least one polar group, an organic peroxide, and an anti-oxidant, the organic peroxide accounting for 0.2 to 100 parts by weight, for 100 parts by weight of the copolymer, and the anti-oxidant accounting for 0.02 to 50 parts by weight, for 100 parts by weight of the copolymer. Also, methods for preparing the masterbatch and to the uses of said masterbatch for manufacturing insulating layers for electric cables and for limiting or preventing the water tree phenomenon for electric cables.