The effect of plasticizers on thermoplastic starch compositions obtained by melt processing

The effect of the type and amount of plasticizer on the mechanical, thermal and water-absorption properties of melt-processed thermoplastic starch was investigated. In general, monohydroxyl alcohols and high molecular weight glycols failed to plasticize starch, whereas shorter glycols and sorbitol were effective. The quantity and type of plasticizer did not affect appreciably the crystallinity of the processed samples, but influenced the mechanical properties of these TPS in two opposite ways, viz. a softening effect due to the plasticizing of the amorphous phase and stiffening one due to an antiplasticization effect.