甘蔗渣/废旧聚乙烯发泡复合材料的制备及研究

【作者】 涂芳；

【导师】 孙可伟；

【作者基本信息】 昆明理工大学 ， 材料加工工程， 2007， 硕士

【摘要】 我国植物资源丰富，但利用水平还很低，随着农村生活水平的不断提高，过去被大量用做燃料的农作物秸杆逐渐被液化气、煤气等清洁燃料所代替，除少数被用于生产饲料外，大部分被焚烧处理，这不仅对环境造成了损害，更是对自然资源的严重浪费。另一方面，随着我国经济的快速发展，塑料用量逐日剧增，造成了大量塑料的废弃，给环境带来了不小负担，因此国家越来越重视塑料回收利用的问题。在这样的背景下，使用植物纤维填充改性废旧塑料生产木塑复合材料，不仅可以有效地利用植物纤维和废旧塑料，防止污染，保护环境，同时还可以开发新型仿木材料解决目前木材资源短缺的问题。木塑复合材料兼有木材和塑料的特点，可以在一些场合替代塑料或木材，但相对于纯塑料来说，其脆性大、冲击强度低；相对于天然木材来说，密度又较大。本文针对这两个弱点，引入发泡工艺，在木塑复合材料的基础上制得发泡木塑复合材料。由于发泡木塑复合材料中的泡孔结构可以钝化裂纹尖端，阻止裂纹的扩展，从而可有效地克服一般木塑复合材料脆性大、抗冲击性能差的缺点，同时泡孔的存在可以降低材料的密度、节省原料。本文以甘蔗渣、AC发泡剂和废旧地膜(主要成分为聚乙烯PE)为主要原料，通过混炼熔融后热压成型的方法制备了甘蔗渣／废旧聚乙烯发泡复合材料。文章首先研究了发泡木塑复合材料的制备工艺及性能，探讨了发泡剂用量、甘蔗渣含量、预热温度对发泡木塑复合材料的力学性能、密度及吸水率的影响，并通过正交试验法确定了制备发泡木塑复合材料的最佳工艺组合为：发泡剂用量为1.0份，甘蔗渣含量为20份，预热温度为200℃。用扫描电镜观察了材料的微观结构，计算得发泡木塑复合材料的发泡倍数为1.38，孔隙率为27.9％。另外，针对甘蔗渣与废旧聚乙烯界面相容性差的问题，研究了改善发泡木塑复合材料界面相容性的途径。采用了物理、化学以及两者相结合的方法来提高甘蔗渣与聚乙烯两相间的相容性，比较了碱(NaOH)处理、硅烷偶联剂(KH550)处理、马来酸酐接枝聚乙烯(MAPE)处理及双重处理等处理方法对复合材料力学性能的影响。结果表明：对于拉伸强度和弯曲强度来说，单独处理时以硅烷偶联剂的效果最好，MAPE次之，NaOH处理效果不大；NaOH与硅烷偶联剂双重处理、NaOH与MAPETA重处理对拉伸强度和弯曲强度具有协同增强作用，而硅烷偶联剂和MAPE的双重处理具有对抗减弱作用。对于冲击强度，单独处理以NaOH处理的效果最好，MAPE次之，硅烷偶联剂效果不大，双重处理对复合材料冲击强度没有起到额外作用。更多还原

【Abstract】 Vegetable fiber resources is rich in Our country, but its utilization rate is very low. Along with the village life level unceasing enhancement,the vegetable fiber which massively used as fuel in the past is being replaced by the clean fuel such as the liquid gas, the coal gas and so on. Except minority use to produce the feed, majority is burnt down, this is not only harmful to the environment, but also waste the natural resource seriously. On the other hand, along with the fast development of our country economy,the amout of plastic used sharp increase, so massively waste plastics are abandoned, therefore the country took the plastic recycling value more and more. Under such background, using vegetable fiber and waste plastic producing wood plastic composites(WPC), not only may effectively use the vegetable fiber and waste plastic, protect the environment, but also may develop new imitating-wood material solve the timber resources short question at present.WPC(Wood Plastic Composites) has been researched much currently. Though WPC has many advantages of wood and plastic, the mechanical performances such as tenacity and impact strength are lower than plastic,and density is greater than wood. In this paper, according to these weaknesses, foamed WPC has been prepared to increase impact strength and decrease density due to the foams.Foamed WPC has been prepared with bagasse, AC foaming agent and waste mulching film(PE) by moulding. The effect of foaming agent usage, bagasse content, preheating temperature on the properties of Bagasse/Waste PE Foamed WPC were studied, and the best parameter were certained by orthogonal experiment: the usage of AC foaming agent was 1.0 per, the content of bagasse was 20 per and the preheating temperature was 200℃. The microtectology of composites fracture was viewed by SEM. The foam multiple of the foamed WPC is 1.38,and the porosity is 27.9%.Additionally, the ways of improving interfacal compatibility of Foamed WPC were studied. The ways of physical, chemical and both were used to improve the compatibility. The effect of alkaloid,silane coupling agent, MAPE on the manchanical propertity of Bagasse/Waste PE Foamed WPC were studied. The research indicated that, for tensile strength and flexural strength, when handle alone, the effect of silicon coupling agent was best, MAPE takes second place,effect of NaOH handling was not large. NaOH and silicon coupling agent double handling,NaOH and MAPE double handling had synergism, but silicon coupling agent and MAPE had confrontation role. For impact strength, individual handling with NaOH was best, MAPE takes second place, the effect of silicon coupling agent was not large. Double handling had no extra function on impact strength.更多还原