Crystallization Behaviours of Poly(vinylidene fluoride) (PVDF) Nanocomposites with MoS2 Nanosheets with Different Surface Functional Groups

Abstract

The crystallization behaviours of amorphous poly(vinylidene fluoride) (PVDF) nanocompositesmodified with two different kinds of molybdenum disulfide (MoS2) at different filler loadings were investigated in detail in this work. The crystallinity, melting temperature and crystallization temperature of the PVDF/MoS2 nanocomposites were transformed from α-phase to β-phase with the addition of MoS2, MoS2-COOH and MoS2-NH2. During isothermal cold crystallization, the overall crystallization rate of PVDF was slowed with increased MoS2 loading relative to that of neat PVDF. Moreover, the crystallization temperature of the PVDF nanocomposites increased with the addition of MoS2 despite the cooling rate during nonisothermal cold crystallization. DMA tests showed that the storage modulus of PVDF was decreased with the addition of MoS2, while those of PVDF/MoS2-COOH and PVDF/MoS2-NH2 were enhanced to different degrees. The decomposition of the PVDF/MoS2 nanocomposites were also discussed. Relative to neat PVDF, the thermal stability of PVDF was obviously improved with the addition of MoS2, MoS2-COOH and MoS2-NH2, which could be ascribed to the increased degree of crystallinity.