| abstract |
PCT No. PCT/SE92/00491 Sec. 371 Date Apr. 21, 1994 Sec. 102(e) Date Apr. 21, 1994 PCT Filed Jul. 1, 1992 PCT Pub. No. WO93/08222 PCT Pub. Date Apr. 29, 1993The invention concerns an unsaturated ethylene copolymer, a method for producing the ethylene copolymer, and the use of the ethylene copolymer in compositions for producing cross-linked structures, such as material for electric cables. In the method, ethylene and at least one monomer which is copolymerizable with ethylene and includes a polyunsaturated comonomer having a chain of at least 8 carbon atoms and at least 2 non-conjugated double bonds, of which at least one is terminal, are polymerized at a pressure of about 100-300 MPa and a temperature of about 80 DEG -300 DEG C. under the action of a radical initiator. The polyunsaturated comonomer preferably is an alpha , omega -alkadiene having 8-16 carbon atoms, most preferred 1,9-decadiene. Apart from the polyunsaturated comonomer, polymerization may also involve another vinyl-unsaturated monomer, preferably containing at least one functional group selected from hydroxyl groups, alkoxy groups, carbonyl groups, carboxyl groups and ester groups. The ethylene copolymers produced have an increased degree of unsaturation, which can be used for cross-linking the ethylene copolymer or grafting reactive groups. |