超细硫酸钡和轻质碳酸钙协同增韧聚乳酸混杂材料的制备及性能

采用熔融共混和模压成型工艺制备超细硫酸钡(BaSO_4)和轻质碳酸钙(CaCO_2)协同增韧聚乳酸(PLA)混杂材料。在保持CaCO_2质量分数恒定的情况下,着重考察了BaSO_4的含量对混杂体系的微观结构、力学性能、熔体流动速率和热稳定性的影响。结果表明:适量BaSO_4的引入在基体中分散均匀且界面结合良好,显著提高了材料的韧性。当BaSO_4的质量分数为15%时,PLA混杂材料的冲击韧度和断裂伸长率较PLA/CaCO_2体系分别提高了60.38%和151.90%。随着BaSO_4含量的增加,拉伸强度逐渐下降,而弹性模量却持续上升。总体上,BaSO_4的引入降低了PLA混杂材料的熔体流动速率,但对PLA的热分解行为影响甚微。

Fabrication and Properties of Poly (lactic acid) Hybrid Composites Synergistic Toughened by Ultra-fine Barium Sulfate and Light Calcium Carbonate

The poly (lactic acid) (PLA) hybrid composites consisted of ultra‐fine barium sulfate (BaSO4 ) and light calcium carbonate (CaCO3 ) inorganic particles were fabricated via molten blending and compression molding .T he effect of BaSO4 mass fraction on the morphologies ,mechanical proper‐ties ,and melt flow rate (MFR) as well as thermal stability of hybrid composites were investigated , under the condition of fixed content of CaCO3 .Results show that adequate BaSO4 is dispersed homog‐enously in the matrix and the inorganic particle‐PLA interfacial adhesion is well .PLA is synergistical‐ly toughened significantly by BaSO4 .With 15% content of BaSO4 ,the impact toughness and breaking elongation of the PLA hybrid composites are increased by 60 .38% and 151 .90% ,respectively ,com‐pared to PLA/CaCO3 sample .As BaSO4 increases ,the tensile strength decreases monotonically ,while the elastic modulus of samples increases .On the w hole ,the melt flow rate of the composites is de‐creased with the presence of BaSO4 .However ,little effect of BaSO4 on the thermal behavior of PLA is observed .