Novel approach toward poly(butylene succinate)/single-walled carbon nanotubes nanocomposites with interfacial-induced crystallization behaviors and mechanical strength

Biodegradable poly(butylene succinate) (PBS)/single-walled carbon nanotube (SWCNT) nanocomposites were successfully prepared through silication and physical blend between PBS and acyl aminopropyltriethoxysilane functionalized single-walled carbon nanotube (SWCNT-APTES), which was obtained from acylate between 3-aminopropyltriethoxysilane and acyl chloride functionalized single-walled carbon nanotube. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) observations revealed that the PBS chains were covalently attached to the SWCNT-APTES by hydrolysis. PBS/SWCNT-APTES nanocomposites after hydrolysis exhibited strong interfacial interaction between SWCNT-APTES and PBS matrix, leading to a less agglomeration. However, the PBS/SWCNT-APTES nanocomposite prepared by only physical blend without hydrolysis exhibited severe reagglomeration of SWCNT in the PBS. The addition of SWCNT-APTES enhanced the crystallization of the PBS in the nanocomposites for both approaches of hydrolysis and physical blend due to the heterogeneous nucleation effect while the crystal structure of PBS remained. Especially, a more significant increase of crystallization rate for physical blend was present as comparison to PBS/SWCNT-APTES after hydrolysis due to the higher diffusion constant, which is attributed to the change of surface properties of nanotubes. Furthermore, the incorporation of SWCNT-APTES improved the storage modulus of the nanocomposites compared with that of neat PBS. The PBS/SWCNT-APTES nanocomposites after hydrolysis showed of higher tensile strength than PBS/SWCNT-APTES nanocomposite without hydrolysis.