Study on the lubrication behavior of low molecular weight poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate) ternary copolymer in rigid PVC

Herein, low molecular weight poly(vinyl chloride- co -n-butyl acrylate- co -vinyl acetate) (PCBV) ternary copolymers with varied copolymer composition was employed as a novel polymeric lubricant in rigid PVC. The lubrication effect of PCBVs on the melting process and mechanical properties of the final PVC products were fully investigated. The results indicated that PCBV can serve either as an internal or as an external lubricant depending on its composition. PCBV-45.5 terpolymer (PBA% ~ 45.5%) exhibits outstanding balance both internal and external lubricating roles. SEM-EDS results show that addition PCBV-45.5 form a film on the surface of PVC grains as similar as that adding both internal and external lubricants. Fusion characteristics and DMTA demonstrate that PCBV-45.5 prolongs the fusion time (26% extension, 1.5 phr) and reduces the glass transition temperature (4.0 °C, 1.5 phr). Finally, the mechanical properties of rigid PVC have been greatly improved by using 1.5 phr PCBV-45.5. In detail, the tensile strength increased from 54 to 59 MPa and the elongation at break increased from 10% to 30%, respectively. Meanwhile, the impact strength of PVC/PCBV-45.5 is 3.6 times that of the blend without addition. The excellent performance of PCBV exhibited great potential as a polymeric lubricant candidate in rigid PVC composites. Graphical