基质增塑型吸水膨胀聚氯乙烯/氯化聚乙烯热塑性硫化胶的形态与性能

Morphology and properties of water-swelling polyvinyl chloride/chlorinated polyethylene thermoplastic vulcanizates with polyvinyl chloride plasticized

以交联聚丙烯酸钠(CPNaAA)作为吸水材料,采用动态硫化法制备了聚氯乙烯(PVC)/氯化聚乙烯(CM)共混型热塑性硫化胶(TPV),考察了基质PVC的增塑对TPV力学性能、微观形态、吸水性能及动态黏弹性能的影响。结果表明,在PVC中添加邻苯二甲酸二辛酯增塑后,PVC/CPNaAA/CM TPV的拉伸强度、撕裂强度和硬度下降,但扯断伸长率明显增大;基质的增塑使得PVC/CPNaAA/CM TPV的吸水性能获得明显改善,且当基质PVC中邻苯二甲酸二辛酯的用量为60份(质量)时,TPV在蒸馏水中浸泡200 h的吸水率可达2 100%;在应变扫描模式下,PVC/CPNaAA/CM TPV出现了明显的Payne效应,且随着基质增塑程度的提高,体系的Payne效应有所减弱。

Polyvinyl chloride （ PVC ）/chlorinated polyethylene （ CM ） thermoplastic vulcanizates （ TPV ） was prepared by dynamic vulcanization with crosslinked sodium polyacrylate（CPNaAA） as water absorbent material, and the influence of dioctyl phthalate amount in PVC matrix on the mechanical properties, morphology, water-swelling properties and the dynamic viscoelasticity was investigated. The results showed that increasing the dioctyl phthalate amount in PVC matrix led to the decrease of the tensile strength, tear strength and hardness; however, the elongation at break increased remark- ably; incorporation of dioctyl phthalate into PVCmatrix resulted in the remarkable increase of water- swelling ratio of the PVC/CPNaAA/CM TPV espe- cially when the dioctyl phthalate amount was more than 40 phr. When the amount of dioctyl phthalate in PVC matrix was 60 phr, the water-swelling ratio of the TPV in the distilled water reached to 2 100% after 200 h immersion. PVC/CPNaAA/CM TPV showed the typical Payne effect, which was weak- ened with increasing the dioctyl phthalate amount in PVC matrix.