The Preparation And Property Research Of EPDM/PB TPV

In this paper, thermoplastic vulcanizate (TPV) based on ethylene-propylene-diene monomer (EPDM)/polybutylene (PB) blends were prepared by dynamic vulcanization. The mechanical properties, morphology, Payne effect, compression set and thermal behavior of TPV were researched systematically. The compatibility of EPDM and PB was researched. Effect of processing on the properties of TPV was studied to determine the best prcessing. Different reinforcing agent was added to TPV and then the Payne effect was studied.The factors of TPV compression set were studied systematically. Regularity of thermal oxygen aging and mechanical properties of TPV after remilling was studied.The results showed that:The compatibility between EPDM and PB was wonderful. TPV prepared by dynamic vulcanization was soft and tough.With the content of PB increasing, tensile strength,elongation at break,hardness, tensile permanent deformation, compression set increased.The remain rate of aging properties was above 80%.The remain rate of mechanical properties after remilling was above 70%.The TGA curves of TPV showed two obvious stages.The process of dynamic vulcanization did not change the crystal type of PB, we could seethe existence of crystallization by polarizing microscope. We could also see that the microstructure of fracture was flat by SEM. We could see obvious "Sea-Island" structure in TPV that was inspected with OSO4 vapors.With the increase of sulfur content, compression set became gradually smaller, but the compression set became bigger under high temperature. TPV prepared by peroxide vulcanization had lower flowability and worse mechanical properties.The compression set became larger but it was not influenced by high temperature. In a word, TPV prepared by 60 phr EPDM,2 phr sulfur, rheometer speed in 60r/min had the best mechanical properties.CB、PP、silica and modified silica was used to improve the mechanical properties of TPV. CB could improve the mechanical properties of TPV and reduced compression set. The silica modified by KH550 has better reinforcing action but it increased compression set. TPV reinforced by silica showed obvious Payne effect and bigger G’ and G".The fillers reduced the crystallinity of PB, at the same time the original lattice was destroyed. With in set limits, PP can improve the mechanical properties of EPDM/PB TPV.