Abstract：Hydrogen bonding had a significant effect on the properties of polymer blends. Thermoplastic polyvinyl alcohol (TPVA)/ethylene-vinyl alcohol copolymer (EVOH) blends with different mass ratios were prepared by melt-blending extrusion with a twin-screw extruder. The effects of hydrogen bonding on the thermal and rheological properties of the blends were studied by differential scanning calorimetry (DSC), dynamic thermomechanical analysis (DMA), melt flow measurements and capillary rheology. The results showed the presence of strong hydrogen bonding between TPVA and EVOH. TPVA and EVOH in the blends were compatible but not miscible, both TPVA and EVOH crystallized independently. The changes of crystallization temperature (Tc) and melting temperature (Tm) as a function of EVOH content in the blends had linear relationships. The melt flow rates of the blends were significantly higher than those of the two starting materials and a "melt flow rate peak" phenomenon was observed. The apparent shear viscosities as a function of blend composition were dependent on the shear rates, which is possibly due to the strong intermolecular hydrogen bonding in the blends.
LI Cong,WANG James Hongxue,BAI Yu et al. Study on the Preparation and Properties of Melt-Extruded TPVA/EVOH Blends[J]. Chemical Reaction Engineering and Technology, 2022, 38(6): 525-533.
