Fabrication and Physical Characterization of Biodegradable Poly(butylene succinate)/Carbon Nanofiber Nanocomposite Foams

Nanocomposites of biodegradable poly(butylene succinate) (PBS) and carbon nanofibers (CNFs) were prepared by three different methods, that is, solution blending, melt compounding, and solution and subsequent melt blending (SOAM) method, among which the SOAM method, where nano-scale fillers and polymer matrix are solution-blended and subsequently melt-mixed in a torque rheometer, is a two-step process for obtaining polymer nanocomposite. Dispersion of CNFs in the PBS matrix was characterized by FE-SEM, while thermal and mechanical properties were analyzed by thermogravimetric ananlysis (TGA) and universal test machine (UTM), respectively. The PBS/CNF nanocomposites were then converted to foams by employing a chemical blowing agent (CBA) in the melt. The presence of CNFs increased the melt viscosity of PBS so that the PBS/CNF nanocomposite foams were produced without modifying the chemical structure of the PBS. Nanocomposite foams prepared by the SOAM method showed higher physical properties compared with those prepared by the solution blending and the melt mixing. Cell size and blowing ratio increased with the increase in the CBA content, blowing temperature and time. Cell morphology of the nanocomposite foams was examined by optical microscopy, and the cell size distribution was also investigated.