| 摘要 |
PURPOSE:A rubber composition mainly consisting of natural rubber or styrene- butadiene rubber that is made by adding a specific low-molecular-weight butadiene polymer, thus showing good flow processability snd giving vulcanized products of high impact resilience, and good mechanical properties. CONSTITUTION:To 100pts.wt. of solid rubber mainly consisting of natural rubber or styrene-butadiene rubber, are added 3-35pts., preferably 5-25pts., of a low- molecular-weight butadiene polymer of 13,000-100,000 viscosity average molecular weight and less than 30% bound vinyl content. The butadiene copolymer is very effective, when it is of 20,000-75,000 viscosity average molecular weight and contains less than 15% of the polymer of less than 3,000 molecular weight measured by the gel-permeation chromatography and a butadiene-isoprene copolymer that is produced by the anion polymerization and ranges from 97/3-30/70 in the butadiene/isoprene weight ratio is preferred. |
