Affiliation:
1. Biodegradable Polymers Research Unit, Department of Chemistry and Centre of Excellence for Innovation in Chemistry, Faculty of Science, Mahasarakham University, Mahasarakham 44150, Thailand
Abstract
The crystallization behaviour, mechanical properties and heat resistance were determined for mixtures
of poly(L-lactide)-b-polyethylene glycol-b-poly(L-lactide) (PLLA-PEG-PLLA) blended with
poly(D-lactide)/poly(L-lactide) with m.w. of 6,000 g/mol (PDLA6k/PLLA6k). These blends were
prepared by melt blending. PLLA-PEG-PLLA/PDLA6k/PLLA6k ratios of 90/10/0, 90/7.5/2.5, 90/5/5,
90/2.5/7.5 and 90/0/10 %wt. were investigated. PLLA-PEG-PLLA/PDLA6k and
PLLA-PEG-PLLA/PLLA6k blends were also prepared for comparison. The presence of
PDLA6k/PLLA6k mixture improved crystallization and heat resistance of PLLA-PEG-PLLA and
this improvement was related to increased PDLA6k content. However, the 90/10/0 blend film was
brittle but 90/7.5/2.5, 90/5/5, 90/2.5/7.5 and 90/0/10 blend films were not. The PLLA6k blending
enhanced film flexibility. The results suggested that the PLLA-PEG-PLLA blends with controllable
mechanical properties and heat resistance can be prepared by varying the PDLA6k/PLLA6k ratio for
use as flexible and heat-resistant biodegradable bioplastics.
Publisher
Asian Journal of Chemistry