(572a) Blends of High Density Polyethylene With Chlorinated Polyethylene: Morphology, Thermal, Rheological and Mechanical Properties

Blends of high density polyethylene with chlorinated polyethylene were generated using melt mixing. Chlorinated polyethylene of two different chlorination contents was used and its amount in the blends was varied from 1% till 30%. The rheological, thermal, mechanical and morphological properties of the blends were characterized along with miscibility analysis. The thermal properties indicated better mixing of the CPE polymer in HDPE at lower CPE concentration and reduced mixing or immiscibility at higher concentration of CPE. However, the amount and type of immiscibility was suggested to be different in both CPE25 and CPE35 systems. The rheological analysis of the data using Cole-Cole, Han-Chuang and van Gurp plots also confirmed the miscibility of CPE25 blends (except for 30% CPE25 blend at lower frequency) whereas CPE35 blends with 10-30% CPE content were immiscible. Maximum increase in the rheological properties was observed at 2% CPE content. The mechanical properties of the CPE25 blends were superior than the corresponding CPE35 blends especially at higher CPE concentration where effects of immiscibility as well as matrix plasticization played a role. The morphology characterization using TEM indicated change in the crystalline features of the polymer in the case of CPE35 blends. The optical microscopy also confirmed the better mixing of CPE25 polymers in HDPE than CPE35. The CPE25 blends exhibited small dispersed areas of CPE phase which may indicate reduced mixing but were still well mixed as confirmed by the rheological and DSC analysis. However, the blends of CPE35 with 10% CPE content onwards had significant phase immiscibility.