Chemorheology of crosslinked polyisoprene/poly(butadiene co-styrene) blends

✍ Scribed by Saburo Tamura; Kenkichi Murakami

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 897 KB
• Volume: 33
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1987.070330520

✦ Synopsis

Physical and chemical properties of IR/SBR blend systems crosslinked by dicumyl peroxide were investigated in detail. In order to study physical structure of cross-linked rubber blends, measurement of birefringence of extended samples and observation by scanning electron microscope (SEM) of ones ruptured in liquid nitrogen were also carried out. In the vicinity of IR/SBR = 30/70 (weight ratio) the phase structure of blends was reversed. The size of domain was in about 0.2 to 0.7 pm dependent on the blend ratio. In preparing the cross-linked rubber blends, cross-linking reaction seemed to occur independently in each rubber phase. The birefringence linearly increased with the blend ratio in the range of IR/SBR = 100/0 to 40/60 and then largely increased in IR/SBR < 30/70. Stress relaxation of rubber blends was observed a t 373 K in both air and nitrogen. Chemical stress relaxation of these systems could be represented by a combination of rate constant of stress relaxation and volume fraction of each cross-linked rubber, that is, the degradation of the networks of cross-linked rubber blends occurred independently in each rubber phase.