Effect of Glycerol and Reactive Compatibilizers on Poly(butylene succinate)/Starch Blends

Abstract

A one-step process in an internal mixer was used to prepare Poly(butylene succinate) (PBS)/high-loading modified tapioca starch (30-40 wt%) blends with low glycerol content (10-20 wt% of starch) as a plasticizer. To promote a good compatibility, two reactive agents, maleic anhydride (MA)/peroxide and methylene diphenyl diisocyanate (MDI), were selected and compared. The mechanical properties, morphology, and Molau test of the blends were investigated. The compatibility of PBS/starch blends was improved by both reactive agents at the suitable plasticizer loading (glycerol 10 wt% of starch). It was demonstrated that increasing mechanical properties resulted in good adhesion of PBS/starch interface and small evenly dispersed starch particles. MA/peroxide of 0.20/0.01 phr/phr and MDI of 0.2 phr were sufficient to improve the mechanical properties of PBS/starch (60:40 and 70:30) blends at 10 wt% glycerol (of starch). The results from the Molau test confirmed the formation of graft-copolymer at the interface when compatibilizers were added.