Plasticizing Effect of Ionic Liquid on Poly (vinyl alcohol) with Different Degrees of Polymerization

摘要

The plasticized poly(vinyl alcohol) (TPVA) was successfully prepared using poly(vinyl alcohol) (PVA) and 1-butyl-3-methylimidazolium bromide (BMIMBr). Plasticizing effect of the degree of polymerization (DP) on PVA was investigated by differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and melt flow indexer (MI). It was found that new hydrogen bonds between PVA and BMIMBr were formed, which was confirmed by the-OH shift of PVA in FT-IR analysis. XRD analysis showed that the original lattice and more irregular molecular chain structures in the amorphous region of PVA were destroyed effectively, which was conducive to the decrease of degree of crystallinity. Moreover, the plasticizing effect decreased with the increase of DP duo to more molecular entanglements in PVA. TPVA-1799 possessed the largest thermal processing window and best melt flowability, which was significant for melt spinning in the future.