Physical Aging Studies of Styrene-Butadiene and Carbonate-Siloxane Block Copolymers
Abstract
The physical aging process in styrene-butadiene and carbonate- siloxane block copolymers has been studied by monitoring the time dependent changes in mechanical and thermal properties. Specifically, stress-strain, stress relaxation and differential scanning calorimetry experiments were utilized. For the styrene-butadiene systems, it was found that the rate of physical aging increases with decreasing glassy content between 50 and 100% glass. However, the rate must decrease to zero when the percent glass reaches zero. The occurrence of physical aging was also noted in the polycarbonate siloxane block copolymer investigated. The data are discussed in light of the practical ramification of utilizing these block copolymers in material applications.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 19, 1979
- Accession Number
- ADA079608
Entities
People
- Garth L. Wilkes
- Martin R. Tant
Organizations
- Virginia Tech