乙酰化前后木质素对甲酚与聚乳酸复合成膜性质影响的比较

Comparison on properties of acetylated lignocresol-polylactic acid film before and after acetylation

本文讨论乙酰化前后木质素对甲酚的结构变化以及其与聚乳酸(PLA)复合成膜的性质特点。重点研究了不同羟基含量的乙酰化木质素对甲酚的用量对其与PLA复合膜的拉伸强度及断裂伸长率的影响。木质素对甲酚经过乙酰化处理后,通过红外光谱和紫外光谱对比了吡啶-冰醋酸法和乙酸酐法两种方法的乙酰化效果。通过使用不同羟基含量的乙酰化木质素对甲酚与聚乳酸共混铺膜后,用拉力测试仪测量膜的力学性质。结果表明,两种方法在乙酰化后由于木质素酚的羟基和酰基含量不同,对膜的拉伸性能影响不同。当木质素酚的羟基含量从12%降低至5%时,复合膜的断裂伸长率在添加比例从0增加到20%时均有所增高,但膜的拉伸强度在乙酰化木质素酚的羟基含量为8%时,表现出比未添加情况下更高的性质。这说明,乙酰化木质素酚中的羟基与酰基在与PLA复合时共同影响复合膜的力学性质。

This paper discusses structure features of Jingo-cresol before and after acetylation. Two methods were used in acetylation. The changes of hydroxyl group amounts were mainly focused on. When the acetylated lingocresols were composited with polylactic acid （PLA）, the tensile strength and elongation at break were changing with the addition amounts of lingo-cresol. When the acetylation degree was higher, the lignocresol with lower hydroxyl group amounts （5%） make the elongation at break increased, the addition amount of lignocresol is allowed up to 20%. When the hydroxyl group amounts were 8%, increasing with the addition amount of lignocresol （0-20%）, the tensile strength of composite film became higher than PLA without any additives.