cis‐trans Isomerization in polyisoprenes. Part IV. Conversion of gutta‐percha to a polymer which is rubber‐like at room temperature

Abstract

Treatment of the partly crystalline polyisoprene gutta‐percha with thiolbenzoic acid, dibenzoyl disulfide, or sulfur dioxide transforms it into a polymer which is rubber‐like at room temperature. The vulcanizates obtained from treated gutta‐percha and ordinary gutta‐percha have been examined and found to differ markedly in their stressstrain properties. It is suggested that the above reagents cause trans‐cis isomerization in gutta‐percha and that these changes in configuration are responsible for the changes in physical properties.