聚丙烯基木塑、棉塑和棉木塑复合材料的制备及改性研究

发布时间：2018-03-05 10:16

本文选题：PP基复合材料　切入点：木粉　出处：《暨南大学》2015年硕士论文　论文类型：学位论文

【摘要】：以木粉或废弃棉纤维与塑料共混制备的木塑或棉塑复合材料,具有绿色环保、综合性能较好、成本低廉的优点,显示出广阔的应用前景。但由于强亲水的木质纤维或棉纤维与疏水的热塑性塑料之间的极性差异导致界面粘接强度低和相容性差,从而限制木塑或棉塑复合材料力学性能的提高。因此,本文以层状石墨相氮化碳(g-C3N4)为增强剂制备了改性聚丙烯(PP)基木塑复合材料;以及先采用聚合物将废弃棉纤维硬化,然后加入塑料中制备成棉塑复合材料,或加入木粉和塑料中制备成棉木塑复合材料;并研究了它们的结构性能。具体的研究内容如下:1、将煅烧三聚氰胺制备的g-C3N4与PP、木粉(WF)依次通过挤出造粒、注塑成型得到g-C3N4增强PP基木塑复合材料样品,观察了样品冲击断面的形貌,测试了样品的性能。研究结果发现:层状的g-C3N4在机械剪切力作用下部分脱落成片状并被PP紧密包裹;随着g-C3N4添加量的增加,样品的弯曲模量、拉伸模量、热稳定性和耐水性逐步增加,颜色逐渐变浅;当g-C3N4的添加量为3.0wt%时,其在样品中的分散性良好,综合性能优异。2、利用单体浸泡废弃棉纤维并通过加热聚合形成的硬化棉纤维与PP依次通过挤出造粒、注塑成型得到PP基棉塑复合材料样品,观察了样品的冲击断面形貌,测试了样品的性能。研究结果表明:随着硬化棉纤维添加量的增加,样品中棉纤维与PP之间的界面越明显,纤维被拔出后留下的空腔越多;硬化棉纤维的添加提高了样品的弯曲模量、拉伸模量和热分解温度,但其冲击强度、弯曲强度和拉伸强度都出现先增加后降低的现象;添加10.0t%硬化棉纤维样品的综合性能最佳。3、利用单体浸泡废弃棉纤维后加热聚合的硬化物与PP、WF依次通过挤出造粒、注塑成型得到PP基棉木塑复合材料样品,观察了样品的冲击断面形貌,测试了样品的性能。研究发现:随着硬化棉纤维添加量的增加,棉纤维与PP和WF之间的界面越明显,纤维被拔出后留下的空腔越多,样品的吸水率逐步增加;当硬化棉纤维的添加量在2.5~10.0wt%范围内时,与木塑复合材料相比,硬化棉纤维的添加使样品的弯曲模量和拉伸模量明显增大,而对其弯曲强度和拉伸强度没有明显影响;当废弃棉纤维的添加量为5.0wt%时,样品的冲击强度最佳、综合性能良好。
[Abstract]:Wood plastic or cotton plastic composite prepared by blending wood powder or waste cotton fiber with plastics has the advantages of green environmental protection, good comprehensive performance and low cost. But due to the polarity difference between strong hydrophilic wood fiber or cotton fiber and hydrophobic thermoplastic plastics, the interface adhesion strength is low and the compatibility is poor. In order to limit the improvement of mechanical properties of wood-plastic or cotton-plastic composites, the laminated graphite phase carbon nitride carbon nitride (g-C3N4) was used as reinforcements to prepare modified PP / PP-based wood-plastic composites, and the waste cotton fibers were first hardened by polymer. Then the cotton plastic composite is prepared by adding the plastic into the plastic, or the cotton wood plastic composite is prepared by adding the wood powder and the plastic into the plastic material. The structure and properties of g-C3N4 prepared by calcining melamine, PPand wood flour WF4 were prepared by extrusion granulation and injection molding to obtain g-C3N4 reinforced wood-plastic composites. The morphology of the impact section of the sample was observed and the properties of the sample were tested. The results showed that the laminated g-C3N4 was partially shearing off and tightly wrapped by PP under mechanical shear stress, and the flexural modulus of the sample increased with the increase of the content of g-C3N4. The tensile modulus, thermal stability and water resistance of g-C _ 3N _ 4 increased gradually, and the color became lighter, and the dispersion of g-C _ 3N _ 4 in the sample was good when the content of g-C _ 3N _ 4 was 3.0 wt%. The composite properties were excellent. 2. The toughened cotton fiber and PP prepared by monomer soaking and heating polymerization were used to extrude granulation and injection molding to obtain PP matrix cotton plastic composite material samples. The impact section morphology of the samples was observed. The results showed that with the increase of the content of hardened cotton fiber, the interface between cotton fiber and PP in the sample was more obvious, and the more cavity was left after the fiber was pulled out. The addition of hardened cotton fiber increased the bending modulus, tensile modulus and thermal decomposition temperature of the samples, but the impact strength, bending strength and tensile strength of the samples increased first and then decreased. When 10.0t% harden cotton fiber was added, the best comprehensive properties were obtained. The PP / cotton wood / plastic composite material was obtained by extrusion granulation and injection molding by heating the cured material and PPN WF after the waste cotton fiber was soaked in the monomer. The impact section morphology of the sample was observed and the properties of the sample were tested. It was found that the more obvious the interface between cotton fiber and PP and WF was with the increase of the content of hardened cotton fiber, the more cavity was left after the fiber was pulled out. When the content of hardened cotton fiber is in the range of 2.5 ~ 10.0 wt%, compared with wood-plastic composite, the flexural modulus and tensile modulus of the sample are obviously increased with the addition of hardened cotton fiber. When the content of abandoned cotton fiber is 5.0 wt%, the impact strength of the sample is the best and the comprehensive properties are good.
【学位授予单位】：暨南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332

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