Paper Title
Rubber Seal Compound Design: N-pentane Resistant Rubber of NR/NBR with Different Acrylonitrile Content and Homogenizer or Compatibilizer

Abstract
Rubber seal in Liquified Petroleum Gas (LPG) at the tube valve must be meet Indonesian National Standard (SNI 7655:2010), which has high n-pentane resistance properties. This study aims to design a rubber seal compound wherein meets SNI 7655:2010 requirements. The compound design was used natural rubber (NR) and acrylonitrile butadiene rubber (NBR) with different acrylonitrile content and homogenizer or compatibilizer in specified dosage. Mixing process held in two rolls open mill with a masterbatch system. Curing characteristics, mechanical properties, ageing properties, and swelling performance of NR/NBR in n-pentane were assessed. Afterward, this result was compared to the minimum requirement in SNI 7655:2010. The study obtained that the addition of NR can improve the mechanical properties of rubber seal, especially tensile strength and elongation at break. Compatibilizer exhibits better mechanical properties improvement in low acrylonitrile content of NBR while homogenizer is shown better mechanical properties improvement in low acrylonitrile content of NBR. These compound design study revealed that NR/NBR with high acrylonitrile content and homogenizer (40/60H) is the best formulation for LPG rubber seal, wherein adequate Indonesian National Standard (SNI 7655:2010) requirement. Keywords- Acrylonitrile Butadiene Rubber, Natural Rubber, N-pentane, Rubber Seal