ABSTRACT
The super toughed poly(l-lactic acid) (PLLA) blends with various content of Ethylene/butyl methacrylate/Glycidyl Methacrylate Terpolymer (GEBMA) were prepared by melt compounding. The blend was an immiscible system but had good compatibility due to the chemical reaction between the epoxy groups of GEBMA and the end group of PLLA during the blending process. The addition of GEBMA suppressed the cold crystallization and non-isothermal melt crystallization of PLLA. GEBMA was a very effective toughening agent for PLLA. The addition of only 15â¯wt% GEBMA, the elongation at break and impact strength of the blend were significantly improved compared to neat PLLA, which were 63 and 18 times that of neat PLLA, respectively. Scanning electron microscopy (SEM) images of the impact fracture surfaces of the blends showed a large amount of cavities and plastic deformation in the blend, which induced energy dissipation and therefore led to the improvement in toughness of the PLLA/GEBMA blends. For the PLLA/GEBMA blown films, the addition of GEBMA significantly improved the flexibility of PLLA/GEBMA blown film. The tear strength reached a maximum of 143.5â¯kN/m in the machine direction (MD) and 166.7â¯kN/m in the transverse direction (TD). Moreover, the biodegradation of PLLA was enhanced after blends preparation.
Subject(s)
Endopeptidase K/chemistry , Epoxy Compounds/chemistry , Methacrylates/chemistry , Polyesters/chemistryABSTRACT
In this work, rare earth europium was combined with different organic ligands to obtain two kinds of rare earth conversion agents, Eu(DBM)4CPC and Eu(TTA)3(TPPO)2. Two kinds of conversion films were successfully prepared by combining them with polylactide and poly(butylene adipate-co-terephthalate). Results showed that the film has excellent light conversion ability and high color purity, and rare earth complexes improved melt flowing property and decreased melt viscosity of blend. At the same time, the elongation at break of the film increased greatly, which could up to 595.0/460.9% in the both machine direction (MD) and transverse direction (TD). The results of GPC show that rare earth complexes can make main chain of PLA scission, which causes rapid molecular weight reduction, and the effect of Eu(DBM)4CPC on the molecular weight of PLA was more significant than Eu(TTA)3(TPPO)2. SEM shows that the complicity of PLA and PBAT has been improved, the dispersed phase of the blend is more uniform. DSC shows that both rare earth complexes can improve the crystallization capacity of PLA. And with the addition of cetylpyridinium chloride could improve the compatibility of rare earth complexes and polymer materials, the light transmittance and hydrophilicity of the film also increased obviously.
