Preparation and Characteristics of Poly(butylene adipate-coterephthalate)/Polylactide Blend Films via Synergistic Efficiency of Plasticization and Compatibilization

Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a compatibilizer.The synergistic effects of the two additives on the mechanical,thermal,and morphological properties of the PLA/PBAT blend films were investigated.The influence of TEC content on the plasticized PLA films and the effect of TDI’s presence on the PLA/PBAT blend films were also studied by comparing them with neat PLA.The results showed a pronounced increase in elongation at break of the plasticized PLA films with increasing TEC levels,but a slight reduction in thermal stability.Also,the addition of TEC and TDI to the blend system not only synergistically enhanced the tensile properties and tensile-impact strength of the PLA/PBAT blends,but also affected their crystallinity and cold crystallization rate,a result of the improvement of interfacial interaction between PLA and PBAT,including the enhancement of their chain mobility.The synergy of the plasticization and compatibilization processes led to the improvement of tensile properties,tensile-impact strength,and compatibility of the blends,accelerating cold crystallization without affecting crystallization.

Synergistic Effect of Nucleation and Compatibilization on the Polylactide and Poly(butylene adipate-co-terephthalate) Blend Films

Polylactide （PLA） films blended with 10 wt% poly（butylene adipate-co-terephthalate） （PBAT） were prepared by using a twin screw extruder in the presence of the nucleating agent of titanium dioxide （TiO2） and the compatibilizers of toluene diisocyanate （TDI） and PLA-grafted-maleic anhydride （PLA-g-MA）. The synergistic effect of the nucleation and compatibilization on the properties and crystallization behavior of the PLA/PBAT （PLB） films was explored. The results showed that the addition of TiO2 significantly enhanced the tensile strength and the impact tensile resistance of the PLB films while slightly decreased its thermal stability. In addition, the compatibilizers of TDI and PLA-g-MA in the system not only affected the crystallinity and cold crystallization process of the PLB films, but also increased the mechanical properties of them due to the improvement of the interracial interaction between PLA and PBAT revealed by the morphological measurement. The synergistic effects of the nucleating agent and the compatibilizer afforded the blend films with increased tensile strength and impact tensile toughness, improved cold crystallization property and Xc.

Synergistic Efficiency of Tricresyl Phosphate and Montmorillonite on the Mechanical Characteristics and Flame Retardant Properties of Polylactide and Poly(butylene succinate) Blends

The main aim of this research was to investigate the synergistic influence of additives and poly（butylene succinate）（PBS） in improving both the mechanical and flame retardant properties of polylactide（PLA） blends. Tricresyl phosphate（TCP） and montmorillonite（MMT） were the additives used to improve the mechanical characteristics and fire resistance of PLA. Differential scanning calorimetry（DSC） thermograms revealed that the addition of TCP and MMT significantly affected their thermal behaviors. The results of the mechanical and morphological characterizations were in agreement with the changes in thermal behavior. The impact strength and limiting oxygen index（LOI） value of PLA significantly increased with the presence of PBS. The failure mode of the blends as evidenced by scanning electron microscopy（SEM） changed from brittle to ductile. The addition of TCP and MMT produced excellent anti-dripping and self-extinguishing behaviors of the blends, achieving V-0 rating. For the PLA/PBS blends, the synergistic combination of PBS and additives led to an acceleration of cold crystallization, a significant increment of flexibility and impact toughness, and an improvement of flame retardancy.