氯化镁/聚乙二醇复配增塑剂热塑加工聚乙烯醇

采用氯化镁和聚乙二醇对聚乙烯醇(PVA)进行增塑改性, 并利用熔融加工方法制备了PVA薄膜.采用傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、差示扫描量热分析(DSC)和热重分析(TGA)方法研究了由氯化镁和聚乙二醇组成的复配增塑剂与PVA的相互作用及复配增塑剂对PVA结晶性能、热性能和力学性能的影响.结果表明, 由氯化镁和聚乙二醇组成的复配增塑剂能有效地破坏PVA自身的氢键, 降低PVA的结晶度和熔融温度, 提高PVA的热稳定性并扩展PVA的热塑加工温度窗口.由复配增塑剂通过热塑加工方法制得的PVA薄膜具有较好的力学性能, 拉伸强度为31 MPa, 断裂伸长率为466%.

Melt Processing of PVA with Magnesium Chloride and Polyethylene Glycol as the Complex Plasticizer

Poly(vinyl alcohol)(PVA) samples were prepared through the melt processing by employing magnesium chloride and polyethylene glycol(PEG) as the complex plasticizer. The interaction between the complex plasticizer and PVA was investigated by Fourier transform infrared spectroscopy(FTIR). The influences of the complex plasticizer on the crystalline and thermal properties were studied by X-ray diffraction(XRD), differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA), respectively. The results show that the plasticizer can effectively destroy the hydrogen bonding between PVA molecules. The crystallinity of PVA decreased rapidly with the addition of the complex plasticizer. Thermal measurements show that the melting point(T_m) of PVA decreases, the thermal stability improves and thus the thermal processing of PVA are achieved. The obtained PVA film shows good mechanical property, with the tensile strength of 31 MPa and the elongation at break of 466%.