机械力改性芦苇纤维及其对聚乳酸复合材料的阻燃性能研究

Mechanical Modification of Polylactic Acid with Reed Fibers for Flame⁃retardant Application

采用机械力化学法对芦苇纤维(RF)进行磷酰化改性,并将改性后的磷酰化芦苇纤维(MPRF)与聚乳酸(PLA)共混制备复合材料,研究了MPRF对复合材料热稳定性、阻燃性、燃烧性能以及力学性能的影响。结果表明,磷元素成功接枝到芦苇纤维表面,800℃时的残余质量增加;随着MPRF添加量的提高,PLA复合材料的阻燃性能随着MPRF的加入而逐渐增加,当MPRF添加量为40%(质量分数,下同)时,其弯曲强度和拉伸强度可达266.9 MPa和44.7 MPa,极限氧指数为24.6%;最大热释放峰值下降到366.9 kW/m^(2),与PLA相比下降了39.3%,有效降低复合材料的火灾危险性。

The phosphorylation modification for reed fiber(RF)was conducted through mechanical force chemistry,and the modified reed fiber(PRF)was blended with poly(lactic acid)(PLA)to prepare a series of PLA/PRF composites.The effects of PRF on the thermal stability,flame retardancy,combustion properties,and mechanical properties of the composites were investigated.Infrared spectroscopy and thermogravimetric analysis results indicated that phosphorus was successfully grafted onto RF,resulting in an increase in residual char.The flame⁃retardant properties of the compo⁃sites were improved gradually with an increase in PRF content.When 40 wt%of PRF was added,the composite showed flexural strength of 266.9 MPa and tensile strength of 44.7 MPa,and an ultimate oxygen index of 24.6%.Its maximum heat release peak decreased to 366.9 kW/m^(2) by 39.3%compared to pure PLA.