Patent ID: 8415439
Filing Date: 2013-04-09
Classification: C08F

Abstract:
1. An ethylene-tetrafluoroethylene copolymer which consists essentially of ethylene units, tetrafluoroethylene units, units of a monomer (A) having at least two copolymerizable double bonds, and optionally units of a monomer (B) having one copolymerizable double bond, wherein monomer (A) is a monomer represented by the following formula: wherein R monomer (B) is CH the proportion of the tetrafluoroethylene units is from 30 to 70 mol % and the proportion of the ethylene units is from 70 to 30 mol %, based on the total of the tetrafluoroethylene units and the ethylene units, the proportion of units of the monomer (A) is 0.01 to 0.2 mol % based on the total of the tetrafluoroethylene units and the ethylene units to be charged for polymerization, the proportion of units of the monomer (B), when present, is from more than 0 mol % to 10 mol %, based on the total of the tetrafluoroethylene units and the ethylene units, and wherein the copolymer has a ratio (X/W) of its melt tension (XmN) to a load (Wkg) applied for the measurement of the melt tension being at least 0.8.