【作者】 郭胜平；

【导师】 吴伟端；

【作者基本信息】 华侨大学 ， 材料学， 2006， 硕士

【摘要】 作为一种通用塑料，聚苯乙烯（PS）是一种优良的电绝缘材料，其体积电阻率高达10¹⁶Ω·cm，但PS制品在生产、运输、储存和使用过程中会产生静电，使产品吸尘、不易成型加工，极大地影响了PS的应用。因此，添加导电填料，使其具有抗静电性，具有重要的意义。但是，将导电填料添加到聚合物中，常使聚合物的力学性能降低，因此，寻找一种既能使PS有抗静电性，又使其力学性能至少不降低的导电填料，是一件极其有意义的工作。 二硫化钼（MoS₂）为层状结构的半导体（室温电导率为10⁷Ω·cm），其纳米薄片具有相当大的径厚比，有利于纳米MoS₂在聚合物基体中导电网络的形成。纳米MoS₂片具有较多的活性点，有利于提高聚合物基体的力学性能。本论文选用纳米MoS₂片作为PS的导电填料。主要研究工作和结论如下： 1．使用超音速气流磨粉碎较厚的MoS₂片。在高速气流作用下，物料颗粒之间发生冲撞，气流对物料颗粒也产生冲击剪切作用，物料同时与粉碎室发生冲击、摩擦、剪切作用，从而使MoS₂被粉碎。用XRD和SEM表征，结果表明，粉碎后的MoS₂片的厚度明显减小，平均厚度为28.8nm。 2．使用LiCl化学剥离MoS₂。由于MoS₂对Li⁺具有较强的亲和力，使得部分Li⁺可以嵌在MoS₂的层间，再在外力的作用下，使MoS₂得到一定程度的剥离。XRD和SEM分析的结果表明，该法能制备出平均厚度为19.2nm的MoS₂片。分析了这两种剥离方法的机理。由于使用LiCl化学剥离MoS₂一次制备的纳米MoS₂片的量太少，故后续实验中使用气流粉碎制备的纳米MoS₂。 3．原位复合法制备PS／纳米MoS₂复合材料。研究了纳米MoS₂的加入量对苯乙烯聚合的影响，并在此基础上探讨了能使苯乙烯充分聚合的工艺条件，如加热温度，搅拌速度，加热时间，加料顺序等。将制备的复合材料加工成型，用XRD、FTIR、SEM、TG和DSC表征，用高阻仪测试复合材料的电性能。结果表明，复合材料的体积电阻率显著降低，由纯PS的10¹⁶Ω·cm下降到含20％MoS₂时的10⁸Ω·cm，即PS更多还原

【Abstract】 Polystyrene （PS） is a kind of excellent insulator with high volume resistivity, about 10¹⁶Ω·cm, but the PS products will bring static electricity during the course of producing, conveying, depositing and using, which makes PS products are so prone to adsorb dusts that they are hard to mould. What’s more, PS is brittle. These disadvantages dramatically influence PS’s applications. Therefore, research on conductive PS composites is significant, and it is better if PS’s mechanical properties can be improved at the same time.Molybdenum disulfide （MoS₂） is a kind of layed semiconductor （its room temperature conductivity is 10⁷Ω·cm）, its nanosized sheets poss largish diameter/ thickness ratio. This structure is favor of nano-MoS₂’s disperse in polymer matrix. Nano-MoS₂ was choiced as the conductive filler of PS. The main work as follows:①MoS₂ was crushed and exfoliated with supersonic jet mill. Under the function of high speed air flow, material grains will bump each other, and the air flow will produce impact cut toward them, meanwhile, material grains will impact, cut and scrub crushing room, it is no other than these processes prepared MoS₂ nano-sheets.②Nano-MoS₂ was prepared using lithium chloride to exfoliate chemically. MoS₂ has strong appetency to adsorb lithium ions, which makes portion of lithium ions can be embedded the sheets of MoS₂, and joined outside force, MoS₂ can be exfoliated at a certain extent. The results of X-ray diffraction （XRD） and scanning electronic microscope （SEM） indicated that both of the two methods can prepare partially exfoliated MoS₂ nano-sheets effectively. The mechanisms of the two methods were analyzed, too. Since the quantity of nano-MoS₂ prepared by the latter method one time is too few, nano-MoS₂ used in this paper is prepared by the first method.③PS/nano-MoS₂ composites were prepared by in-situ polymerization. The influence of MoS₂ content on the polymerization of styrene was studied, and the technics conditions which can make styrene polymerize fully were discussed at this base, such as heating更多还原