二乙酸甘油酯封端的齐聚L-丙交酯增塑改性聚L-丙交酯薄膜

以二乙酸甘油酯(GD)引发L-丙交酯(LLA)开环聚合合成了二乙酸甘油酯封端的齐聚L-丙交酯(OGLA),并以此为增塑剂,以溶液共混法制备了OGLA与高分子量聚L-丙交酯(PLLA)的共混膜.采用DSC研究了共混膜的T_g和结晶性变化,考察了共混膜的力学性能和渗出性.结果表明:随着OGLA含量的增加,共混物T_g下降,结晶度降低,柔性提高;与聚乳酸相比,随着OGLA含量的增加,拉伸强度、弹性模量有一定程度降低,但断裂伸长率有较大程度的提高,力学性能得到较好的平衡;OGLA增塑体系与GD增塑体系相比较,优势在于避免了小分子增塑剂的渗出.

Properties of Poly(L-lactide)Plasticized with Glycerol Diacetate-Terminated Low Molecular Weight Poly(L-lactide)

Glycerol diacetate(GD)terminated poly(L-lactide)(OGLA)were successfully synthesized by Glycerol diacetate initiated ring-opening polymerization of L-lactide,which was used as a biocompatible plasticizer for high molecular polylactide(PLLA).The differences of T_g and crystallinity were analyzed with DSC and the mechanical property and effusion was illustrated as well.The experiment results showed that stiffness,T_g and the degree of crystallinity decreased with the increasing of OGLA content,while the toughness enhanced.Tensile strength and Young's modulus decline with the increasing of OGLA content,but the elongation at break improved.Plasticizer effusion was also avoided.