【作者】 韩冰；

【导师】 李杨；

【作者基本信息】 大连理工大学 ， 高分子材料， 2012， 硕士

【摘要】 采用自由基原位悬浮聚合方法,由苯乙烯／纳米无机粒子聚合制备聚苯乙烯(PS)纳米复合材料,再以戊烷为发泡剂,浸渍制备可发性聚苯乙烯(EPS)纳米复合材料。本文中,为了使无机粒子能够更好的相容于聚苯乙烯基体,首先对无机粒子进行了表面改性,通过活化指数(H)的测试以及红外光谱的表征(FT-IR),筛选确定了改性剂的种类和工艺条件。同时研究了不同无机粒子对悬浮体系稳定性以及聚合过程的影响规律,实验中是将自制的活性磷酸钙(HAP)、羟乙基纤维素(HEC)和十二烷基本磺酸钠(SDBS)构成有机/无机复合分散体系,考察了此分散体系下复合珠粒的宏观成粒特征以及粒径、粒径分布的控制。利用凝胶渗透色谱仪(GPC)对PS复合珠粒进行表征来讨论无机粒子对聚合物分子参数的影响规律。采用红外光谱仪(FTIR)、核磁共振(1H-NMR.13C-NMR)^X射线衍射(XRD)表征EPS复合珠粒的成功合成。并通过热失重分析仪(TGA)和示差扫描量热仪(DSC)分析无机粒子对复合珠粒热性能的影响。EPS复合珠粒发泡后可模塑成不同型状的复合聚苯乙烯泡沫制品,实验中首次采用扫描电子显微镜(SEM)对泡体内部的微观形貌进行了表征,研究无机粒子对泡孔结构以及发泡过程的影响规律。同时通过测试复合泡沫制品的自熄时间来初步确立了优异的有机/无机复合阻燃配方。并采用相同的制备工艺,由苯乙烯/改性后的颜料粒子原位悬浮聚合得到了彩色EPS复合珠粒。结果表明：以钛酸酯偶联剂为改性剂,并采用干性混合法处理无机粒子的效果最好,其同无机粒子间是以化学键的方式结合,聚合产率也最高；某些种类的无机粒子会影响悬浮体系的稳定性和聚合反应时间；HAP/HEC复合分散体系下,当配比为1：1且总用量占单体的0.43%时制得复合珠粒有用粒径的比例较大,(6-26目)能达到97%左右；无机粒子的用量在一定范围内对复合珠粒的分子量影响不大,但会使分布变窄；一些无机粒子能够提高聚合物的热稳定性但对玻璃化转变温度(Tg)影响不大；在EPS复合珠粒发泡过程中,无机粒子起一定的成核作用,改性后的无机粒子能够均匀地分散在聚合物基体中,其泡孔堆积有序,细密一致,且多为闭孔结构；固定溴含量,采用如下阻燃体系：C/ZnB/Mg(OH)2/RP(配比：1：0.1：1：1),当总量在2.5%时阻燃效果最优,制品的自熄时间仅为0.4s左右；新工艺下制得彩色EPS复合珠粒的色彩丰富鲜艳,颜色均匀一致,会成为今后彩色料的发展方向。更多还原

【Abstract】 Based on radical in situ suspension polymerization. Polystyrene nanocomposites are prepared by the polymerization of styrene/nano-inorganic particle. Then, the hexane for the polymer beads was added to prepare expandable polystyrene nanocomposites.In this paper, surface modifiers were utilized to obtain better compatibility of nano-inorganic particle with polystyrene matrix. The best type of modifiers and process conditions was confirmed by the means of activation index and infrared spectrum. The impact of different inorganic particles on the stability of the suspension system and the polymerization process was also studied. The function of hydroxyapatite/hydroxyethylcellulose/sodium dodecyl benzene sulfonate(HAP/HEC/SDBS)compound suspending agents was investigated. Under this composite dispersion system,The characteristics of beads formation and control of particle size was studied. Polystyrene composite beads were characterized to research on molecular parameters by means of gel permeation chromatography.The expandable polystyrene composite beads were characterized by infrared spectrum analysis, nuclear magnetic resonance(1H-NMR.13C-NMR),X-ray diffraction, thermo gravimetric analyzer and differential scanning calorimetry. The syntactic foam was produced by prefoaming. aging and molding processing.Then,the micro-morphology of this foam was firstly analyzed to study influence law of nano-inorganic particle on the micro-morphology by the means of scanning electron microscope. The optimized flame-retardant formula was determined by changing the proportion and amount of inorganic flame retardant.Color EPS composite beads were prepared by using the same method.The results showed that.the titanates coupling agent that formed a chemical bond with nano-inorganic particle was best; Some types of inorganic particle can affect the stability of suspension system and increase the reaction time;When the ratio of the amount of compound suspending agents(HAP/HEC=1:1) to styrene monomer is0.43%,The particle size of EPS composite beads is moderate and the distribution is concentrative,the content between6-26mesh is about97%; In a certain range of modified nano-inorganic particle amount,the molecular weight of EPS composite beads has a narrower distribution; The thermal stability of EPS containing modified nano-inorganic particle was improved significantly,but Tg of the composite beads changed slightly. In addition, The nano-inorganic particle showed a nucleation function in the foaming process; The composite particle foam moldings, in the presence of modified nano-inorganic particle that can disperse in styrene well, have a high closed-cell content and the size is small and uniform;When the percentage of HBCD is6%and the percentage of compound flame-retardant system (C/ZnB/Mg(0H)2/RP=1:0.1:1:1)is2.5%by the monomer,the fire retardant effects are good,and the self-extinguish time is only in0.4s. Color EPS composite beads prepared by this new process have rich,brilliant and uniform colour,which will be development direction.更多还原