淀粉/聚乙烯醇树脂基可降解薄膜的制备与表征

Preparation and characterization of PVA bio-based biodegradable film

以聚乙烯醇和玉米淀粉为主要原料,采用树皮缩合单宁和木质素作为改性剂,制备力学性能良好的淀粉/聚乙烯醇树脂基复合薄膜。采用扫描电子显微镜观察薄膜的微观形貌,通过拉伸强度和断裂伸长率评估薄膜的力学性能,采用傅里叶红外光谱和电喷雾电离质谱研究薄膜的化学结构,结果表明,采用单宁和木质素改性的淀粉/聚乙烯醇树脂基薄膜的表面光滑,无孔隙和裂痕,木质素、单宁在淀粉/聚乙烯醇体系中既发生了物理共混,又发生了化学反应。单宁和木质素的增加既提高了薄膜的热稳定性和抗紫外可见光的能力又提高了薄膜的力学性能。

The starch/polyvinyl alcohol(PVA) resin-based composite film with good mechanical properties was prepared with PVA and corn starch as the main raw materials and bark condensed tannin and lignin as modifiers.The micro morphology of the film was observed by scanning electron microscope,the mechanical properties of the film were tested by tensile strength and elongation at break.Fourier transform infrared spectroscopy and electrospray ionization mass spectroscopy were used to characterize the main chemical structure of the film.The results showed that the surface of the starch/PVA film modified by tannin and lignin was smooth,no pores and cracks.Lignin and tannin were physically blended and chemically reacted with starch and PVA.The increase of tannin and lignin not only improved the thermal stability and UV visible light resistance of the novel film,but also improved its mechanical properties.