Thermal, morphological and mechanical properties of flexible poly(l-lactide)-b-polyethylene glycol-b-poly(l-lactide)/thermoplastic starch blends

Yaowalak Srisuwan; Yodthong Baimark

doi:10.1016/j.carbpol.2022.119155

Thermal, morphological and mechanical properties of flexible poly(l-lactide)-b-polyethylene glycol-b-poly(l-lactide)/thermoplastic starch blends

Carbohydr Polym. 2022 May 1:283:119155. doi: 10.1016/j.carbpol.2022.119155. Epub 2022 Jan 20.

Authors

Yaowalak Srisuwan¹, Yodthong Baimark²

Affiliations

¹ Biodegradable Polymers Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahasarakham University, Mahasarakham 44150, Thailand.
² Biodegradable Polymers Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahasarakham University, Mahasarakham 44150, Thailand. Electronic address: yodthong.b@msu.ac.th.

PMID: 35153027
DOI: 10.1016/j.carbpol.2022.119155

Abstract

This paper reports a flexible poly(l-lactide)-b-polyethylene glycol-b-poly(l-lactide) (PLLA-PEG-PLLA) melt blended with a thermoplastic starch (TPS). The crystallization, thermal stability, phase morphology and mechanical properties of PLLA-PEG-PLLA/TPS blends were evaluated and compared to PLLA/TPS blends. Addition of TPS suppressed crystallizability for both the PLLA and PLLA-PEG-PLLA matrices. The thermal stability of PLLA-PEG-PLLA was greatly increased by blending with TPS. The PEG middle-blocks enhanced phase compatibility between PLLA-PEG-PLLA and TPS phases. Tensile tests showed that the PLLA-PEG-PLLA/TPS blend films were ductile and very flexible compared to the PLLA/TPS blend films. The obtained PLLA-PEG-PLLA/TPS blends can be utilized as novel flexible bioplastics.

Keywords: Phase compatibility; Poly(lactic acid) (PLA); Polyethylene glycol; Thermal stability; Thermoplastic starch.