为了解决石化资源日益紧缺和开发石化资源带来的环境污染, 以可再生的农林废弃物胡桑枝条为原料制备了可注塑的生物基塑料.将球磨预处理的胡桑枝条粉放置在预冷的Na OH/尿素溶液中以-10℃溶解润胀1 h后, 在捏合机中常温捏合, 冷冻干燥得到捏合改性产物.捏合改性产物与一定量的甘油共混挤出制备生物基塑料.研究了不同溶液配比、甘油用量和甘油共混方式对改性产物力学性能的影响.结果表明:球磨木粉经过复合溶剂Na OH/尿素溶液体系捏合改性后, 具有热塑性, 加入甘油捏合或加入甘油共混挤出, 能得到具有较好力学性能的生物基塑料, 所制备的生物基塑料弯曲强度最大达到26. 10 MPa, 拉伸强度和断裂伸长率分别达到13. 21 MPa和10. 91％.以胡桑枝条木粉为原料, 在Na OH/尿素体系中进行捏合改性后, 木粉中羟基被屏蔽, 结晶度降低, 加入甘油增塑可制备出注塑级生物基塑料, 实现了木粉的全组分高效利用.%In order to deal with the shortage and environmental pollution of petroleum resources, injectionmoulded bio-based plastics were prepared with renewable mulberry branches from farming and forestry disposables. The mulberry branch flour was ball-milled with planetary ball mill and was dissolved in the precooled Na OH/urea solution for 1h at-10 ℃. The mixture was kneaded and then dried in a freeze dryer.Finally, the kneaded products were extruded with a certain amount of glycerol to produce the bio-based plastics.Effects of different solution ratios, glycerol content, and different blending methods with glycerol on the properties of modified products were studied. Results showed that the ball-milled wood flour was thermoplastic after kneading and the end product exhibited better mechanical properties. Under the optimum technological conditions, the flexural strength of the bio-based plastics achieved 26. 10 MPa, the tensile strength and the elongation at break reached 13. 21 MPa and 10. 91％, respectively. After the ball-milled wood flour was kneaded in the aqueous Na OH/urea solution, the hydrogen bonds of the wood flour were shielded and the degree of crystallinity was decreased. The injection-moulded bio-based plastic was prepared successfully by adding plasticizer glycerol into kneaded wood flour, achieving high efficient usage of the whole component of wood flour.
展开▼
