Effect of novel amido ester internal donor on the performance of Ziegler-Natta catalyst for propylene polymerization

Abstract

Various classes of molecules like diethers, succinates, diesters, amido esters are currently being used as internal donors on MgCl2 supported titanium catalysts for isotactic polypropylene as an alternative to phthalate donors owing to their potential health risk laid down by REACH legislation. In the present paper, design and synthesis of a few novel amido ester internal donors with single chiral center (7–11) by mimicking the model amido ester 3 having two chiral centers; and their catalyst preparation method were described. Further preliminary polymerization tests with newly synthesized donor molecules were investigated and results revealed that by structurally mimicking 3 with one chiral center and also with varied substitutional patterns in ester/amido moiety decline the polypropylene activity as well as isotacticity. These donor molecules are ineffective for appropriate coordination on MgCl2 sites on inducing steric hindrance for improved isotacticity; nevertheless also induces poisoning effect for the active Ti centers leading to catalyst fouling in many cases.