酸酐改性硫酸盐木质素增强HDPE复合材料的物理力学性能

针对硫酸盐木质素极性高、与HDPE复合难的问题，本研究使用顺丁烯二酸酐（MA）、丁二酸酐（SA）、邻苯二甲酸酐（PA）改性硫酸盐木质素（KL），并采用注塑法制备KL/高密度聚乙烯（HDPE）复合材料。通过相容性分析模拟了改性KL-HDPE复合材料的相容性，分析复合材料的吸水性和吸水厚度膨胀率，通过三点弯曲表征了复合材料的弹性模量（MOE）和断裂模量（MOR）。结果表明，改性后复合材料的界面相容性提高，与PA改性的KL相比，MA、SA改性的KL与HDPE具有较好的界面相容性。MA、SA改性后的木素-HDPE复合材料吸水速率降低，吸湿尺寸稳定性提高。PA改性的木素-HDPE复合材料吸水速率在前500 h较高，但在500 h以上，随着时间的延长其吸水速率低于未改性木素-HDPE复合材料。其中，MA-PE改性复合材料具有较好的耐水性和吸湿尺寸稳定性。MA、SA、PA改性的木素-HDPE复合材料MOE明显提高，分别提高了71%、42%、17%。MA，SA和PA改性除去了木质素中的大部分羟基，降低木质素的亲水性。改性后的复合材料MOR增加，其中MA改性KL复合材料的MOR增加最显著。

Physical and Mechanical Properties of HDPE-Based Composites Reinforced with Anhydrides Modified Industrial Waste Lignin

Industrial alkali lignin(Kraft lignin)is widely derived from pulping black liquor,which has broad commercial using prospects.However,the high polarity of Kraft lignin(KL)makes it difficult to compound with HDPE.In this study,maleic anhydride(MA),succinic anhydride(SA),and phthalic anhydride(PA)were employed to modify KL.The modified KL/HDPE composite was manufactured using injection molding method.The compatibility of KL-HDPE composites was simulated by compatibility analysis.The water absorption and water swelling rate of the composites were analyzed.The modulus of elasticity(MOR)and modulus of rupture(MOE)of the composites were characterized by three-point bending.The results showed that the interfacial compatibility of the modified composites was improved.Compared with PA modified KL,MA or SA modified KL showed good interfacial compatibility with HDPE.The lignin-HDPE composite modified by MA or SA had reduced water absorption and improved moisture absorption dimensional stability.The PA-modified lignin-HDPE composite showed a little higher water absorption in the first 500 hours,but its water absorption was lower than that of the unmodified lignin-HDPE composite after 500 hours soak.The composites manufactured with MA modified KL exhibited better water resistance and hygroscopic dimensional stability.The MOE of MA,SA,PA modified lignin-HDPE composite were significantly improved(71%,42%,and 17%,respectively).The modification could remove most of the hydroxyl groups in lignin,and the hydrophilicity of lignin was reduced as a result.The MOR of the modified composite increased.The strength increased significantly when composited prepared with MA modified KL.