Preparation and Characterization of Poly(lactic acid)/Poly(butylene adipate-co-terepthalate) Blends and Their Composite

Abstract

Poly(lactic acid) (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) blends and their composite were prepared by melt compounding. Maleic anhydride grafted PLA (PLA-g-MA) was used as a compatibilizer. With the addition of PBAT into PLA, elongation at break and impact strength increased but tensile strength and modulus decreased. Incorporating PLA-g-MA into PLA/PBAT blend improved the mechanical properties of the blend. Tensile properties of blown film prepared from the compatibilized PLA/PBAT blend were better than those of the uncompatibilized PLA/PBAT blend. Incorporating CaCO₃ resulted in increased tensile strength and modulus of the film prepared from the compatibilized blend.

Keywords:

• Biodegradable polymers
• Compatibility
• Mechanical properties
• Thermal properties

ACKNOWLEDGMENTS

The authors wish to acknowledge National Innovation Agency, Suranaree University of Technology, and Center of Excellence on Petrochemical and Materials Technology for financial support, Sand and Soil Co., Ltd. for supplying CaCO₃, and Bags and Gloves Co., Ltd. for preparing blown films.

Notes

^a The degree of crystallinity (x _c ) of PLA is estimated from (▵H_m/) × (100/w), where ▵H_m is the heat of fusion, is the theoretical of 93 J/g for fully crystalline PLA, w is weight fraction of PLA in the sample.