Influence of acrylate processing aid-based ionomer containing lanthanide (La(III)) ion on thermal stability, fusion, transparency and mechanical properties of rigid poly(vinyl chloride)

An acrylate processing aid (ACR)-based ionomer containing lanthanide (La(III)) ion was synthesized and the influences of the ionomer on thermal stability, fusion time, transparency and tensile properties of rigid poly(vinyl chloride) (PVC) were investigated. Results revealed that the ionomer with a suitable La(III) content behaved as a good stabilizer as well as processing aid to the rigid PVC product. The ionomer could accelerate fusion of PVC much more quickly than ACR because of the strong interaction between La(III) carboxylate and PVC. Moreover, it exhibited a stabilizing efficiency comparable to lanthanum and calcium stearates (LaSt 3 and CaSt 2 ). The composite stabilizer of ionomer/zinc stearate (ZnSt 2 ) exhibited an ability to improve initial discoloration better than LaSt 3 /ZnSt 2 and CaSt 2 /ZnSt 2 because the ionomer could form a complex with ZnSt 2 much more slowly than LaSt 3 and CaSt 2 . The compounds stabilized using ionomer/ZnSt 2 exhibited a transparency comparable to those stabilized using organotin or liquid barium/zinc stabilizers, which was much better than those stabilized using LaSt 3 /ZnSt 2 and CaSt 2 /ZnSt 2 . Copyright © 2011 Society of Chemical Industry