Effects of CR Contents on Rubber Vulcanization and Mechanical Properties of NR/CR Blends

NR/CR 고무블랜드에서의 CR조성비가 가황 및 물성에 미치는 영향

  • 안원술 (계명대학교 화학공학과) ;
  • 박동률 (KCW(주) 고무기술연구소)
  • Received : 2011.04.13
  • Accepted : 2011.06.08
  • Published : 2011.06.30


Effects of CR contents in NR/CR blends on the vulcanization kinetics and miscibility were studied by dynamic DSC and TGA, as well as the mechanical properties. While the vulcanization activation energy showed a constant value of $77.5{\pm}2.5$ kcal/mol regardless of CR contents, reaction rate, however, was observed to be somewhat lowered at increased CR contents. Partial miscibility was found between NR and CR phases at lower CR content of 3 wt%, but immiscibility was observed at higher CR content of 21 wt%. Mechanical properties were also affected by this miscibility, showing linear increase of compression set but decrease of tensile strength with CR contents in the blends.


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