Micro construction of poly(epsilon-caprolactone)/poly(L-lactic acid) blend film by solution casting under microwave irradiation.
The micro construction of poly(epsilon-caprolactone) (PCL) and poly(L-lactic acid) (PLLA) blend films fabricated by solution casting under microwave irradiation was investigated by selective enzymatic degradation and scanning electron microscopy (SEM). The results were totally different from the blends obtained by conventional methods. The blend was more homogeneous and the PCL continuous phase more compact as no spherulites and tiny zone separation were observed from the film surface and no PCL network was observed inside the film, and the degradation of a PCL plank by Pseudomonas lipase was significantly retarded. The distributed PLLA micro spheres were enlarged and amorphous. The thermal behavior of the blend by microwave heating revealed that PCL and PLLA underwent a melting process, which induced the variations of the PCL phase and PLLA spheres. The weight loss caused by degradation of the PCL/PLLA blend obtained by conventional methods (B50c) is greater than that of the blend obtained by microwave methods (B50m), which reflects the change in morphology from a loose PCL network (B50c) to a dense PCL plank (B50m).
Department of Polymer Science, College of Chemistry and Molecular Science, Wuhan University, Key Laboratory of Biomedical Polymers, Ministry of Education, Wuhan 430072, China.
Wei
W
Jin
Lijian
L
Liu
D001673:Biodegradation, Environmental; D003460:Crystallization; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D008872:Microwaves; D011091:Polyesters / Q000737:chemistry* / Q000528:radiation effects; D011549:Pseudomonas / Q000201:enzymology; D013696:Temperature
D011091:Polyesters; C016240:polycaprolactone; C033616:poly(lactide); D008049:Lipase