羧基改性聚乙烯醇的制备及水溶性研究

摘要

Polyvinyl alcohol (PVA) with high alcoholysis degree but low crystallinity and high water-solubility was achieved by copolymerization of vinyl acetate (VAc) with acrylic acid (AA) and following alcoholysis. The chemical structures of the obtained polymers were characterized by FTIR and 1H NMR. The influence of AA unit on the crystallinity and water solubility of the modified PVA was investigated by XRD, UV-Vis, and the results indicated that high suppression of the crystallization and significant enhancement of the water solubility were achieved through AA modification. Moreover, the rheological investigation suggested that the relative strength of hydrogen bonding interactions existing between PVA chains was enhanced after AA modification, affording the PVA aqueous solution the possibility of withstanding apparent viscosity under a high shear rate.%通过丙烯酸（AA）与乙酸乙烯酯（VAc）共聚进而醇解的方法合成出具有高醇解度、低结晶度的丙1烯酸改性聚乙烯醇。通过FT-IR和H-NMR对聚合物的化学结构进行了表征；通过XRD、UV-Vis、剪切流变测试等手段研究了丙烯酸结构单元含量对改性PVA的结晶性能、水溶性能和溶液表观黏度的影响。结果显示，通过引入适量丙烯酸结构单元，可降低PVA结晶度，提高PVA水溶性，增强PVA水溶液表观黏度的剪切稳定性。