Preparation and Investigation of the Physical Properties of Biodegradable Blends of Poly(lactic acid), Poly(butylene adipate-co-terethphlate) and Tapioca

• Main Authors: Bo-yan Wu, 吳泊晏
• Other Authors: Keng-Ming Chen
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/r5qdw5

碩士 === 國立臺灣科技大學 === 高分子系 === 94 === In this study, we have blended Poly lactic acid (PLA) with Poly(butylene adipate-co-terethphlate)(PBAT) to enhanced the flexibility and toughness of PLA/PBAT resins for film-blowing. All blends were prepared using a plasti-corder and characterized with tensile properties, thermal properties and morphology analysis. Scanning electron micrographs (SEM) show that the phase separation occurred in the fracture surface leading to poor tensile properties. Therefore, diphenyl methane 4, 4-diisocyanate (MDI) was used as the interfacial compatibilizer to improve the mechanical properties of PLA/PBAT/Tapioca blends. It is evident that the addition of MDI can improve the tensile strength. In addition, since PLA was lack toughness for use, adipate ester (AE) or triacetine (TAc) was added as a plasticizer to improve the ductility of PLA. Significant reduction in melting point (Tm) of the PLA resin was found after adding suitable amounts of AE or TAc. The flexibility and values of elongation at break (εf) of PLA resins were significantly improved after blending suitable amounts of AE or TAc. For instance, �挲 values of more than 280% and 300% were obtained when 10 wt. % of AE and 15 wt. % of TAc were added in PLA resin, respectively. Therefore, mixing AE or TAc with PLA/PBAT/Tapioca/MDI blends did exhibit effect of plasticization. The results also reveal that excessive plasticizer would cause the plastic deformation and decreased the tensile strength.