PLLA/PDLA共混材料的压力诱导流动成型研究

Study on Pressure Induced Flow Molding of PLLA/PDLA Blends

在对左旋聚乳酸(PLLA)与右旋聚乳酸(PDLA)熔融共混材料的结构与性能研究的基础上,采用压力诱导流动成型(PIF)对PLLA/PDLA共混材料进行增韧改性,力学测试显示PIF之后PLLA/PDLA的拉伸强度由未加工时的23.05 MPa提高到34.03 MPa,断裂伸长率由3.4%提高至7.78%,冲击强度由未加工时的13.78 kJ/m^2提高至29.17 kJ/m^2。差示扫描量热和热重测试表明,PIF加工方式不会破坏PLLA/PDLA材料原有耐热性、对热分解温度影响较小。

The same quality of poly(lactic acid)(PLLA)and Poly(D–lactic acid)(PDLA)were melt blended and injected into standard splines,and then toughened by pressure induced flow molding(PIF).The mechanical test show that the tensile strength increase from 23.05 MPa to 34.03 MPa,and the elongation at break increase from 3.4% to 7.78%.Moreover,the impact strength increase from 13.78 kJ/m^2 to 29.17 kJ/m^2,nearly 2.1 times.Differential scanning calorimeter and thermogravimetric analysis tests show that PIF approach did not damage the original heat resistance of PLLA/PDLA materials,while has little effect on thermal decomposition temperature.Therefore,PIF could be a certain guiding significance for the modification and application of PLA.