【作者】 谢建宇；

【导师】 冯亚青；

【作者基本信息】 天津大学 ， 应用化学， 2007， 博士

【摘要】 电泳显示是一种新型的显示技术,它是利用分散在微胶囊内部电泳粒子在电场作用下的电泳运动实现显示的,具有低成本、高亮度、全视角、低能耗和可弯曲等特点。电泳显示用微胶囊和普通微胶囊相比,需要具有光滑的囊壁、较好的透明性、较大的强度和柔韧性。本文基于以上的需求,制备了一系列的微胶囊,并将其应用在电泳显示中,获得了较好的效果。以明胶、明胶-阿拉伯胶和壳聚糖-聚丙烯酸为壁材,四氯乙烯为芯材,通过单凝聚法和复凝聚法制备微胶囊。经过研究发现,以明胶-阿拉伯胶为壁材得到的微胶囊,囊壁光滑、透明性好,对芯材包封率高,达到91.2%。在芯材中加入少量甲苯二异氰酸酯(TDI),可明显增强微胶囊壁强度,使微胶囊的破损率从100%下降为51.2%。以尿素-甲醛为壁材,四氯乙烯为芯材,通过两步原位聚合法和一步原位聚合法制备微胶囊。经过研究发现,一步原位聚合法操作简单,实验重复性好,得到的微胶囊,囊壁较光滑、透明性好,对芯材包封率最高达到96.6%。将复凝聚法和原位聚合法相结合,在脲甲醛树脂微胶囊表面包裹一层明胶,形成双层微胶囊,增加了微胶囊壁的厚度,提高了微胶囊壁的韧性和强度,使微胶囊的破损率从98.1%下降为15.1%。以己二酰氯-三乙烯四胺为壁材,四氯乙烯为芯材,通过界面聚合法制备微胶囊。经过研究发现,界面聚合法操作简单,成囊时间短,得到的微胶囊,囊壁光滑、透明性好、囊壁强度较高,对芯材包封率最高达到93.3%,微胶囊破损率可达48.3%。使用经戊二醛改性的三乙烯四胺,可进一步增强微胶囊强度和柔韧性,使微胶囊破损率下降为36.2%。以汉沙黄10G为原料,Span 80为分散剂,对甲氧基苯胺为电荷控制剂,通过球磨制备电泳粒子。经过研究发现,改性的汉沙黄10G粒子分散性为82.4%,电泳淌度为-0.118cm2V-1s-1。通过上述微胶囊制备方法将汉沙黄10G应用在电泳显示中,研究发现它们在E=30V/mm电场作用下具有可逆的电场响应行为,响应时间为1～3s。更多还原

【Abstract】 Electrophoretic display (EPD), realized by electrophoresis of particles in microcapsules under an electric field, is a kind of new display technology, with such features, as low cost, high brightness, full-view, low power consumption and high flexibility. Compared to other types of microcapsules, the ones for EPD require smooth surface, superior transparence as well as good strength and flexibility. According to above requirements, in this thesis microcapsules were fabricated and applied in EPD with superior performance.Microcapsules were prepared through single coacervation and complex coacervation method, with gelatin, gelatin-gum Arabic and chitosan-polyacrylic acid as wall material, and tetrachloroethylene as core material. It was found that microcapsules with gelatin-gum Arabic as wall material had smooth surface, superior transparence and encapsulation efficiency high to 91.2%. It was also found that strength of microcapsules increased significantly and broken rate of microcapsules decreased to 51.2% from 100% after slight toluene-2, 4-diisocyanate (TDI) was added into wall material.Microcapsules were prepared through two-step and one-step in situ polymerization method, with urea-formaldehyde as wall material, and tetrachloroethylene as core material. It was found that one-step in situ polymerization method was easy to utilize and had good repeatability, and that microcapsules prepared by this method had fairly smooth surface and superior transparence, as well as encapsulation efficiency high to 96.6%. We also tried to combine complex coacervation and in situ polymerization method together: Surface of urea-formaldehyde microcapsules was encapsulated by another layer of gelatin to form a kind of double-layer microcapsule, which had thicker wall, better strength and flexibility, and broken rate decreased to 15.1% from 98.1%.Microcapsules were prepared by interfacial polymerization, with adipoyl chloride-triethylenetetramine as wall material, and tetrachloroethylene as core material. It was found that this method could be utilized easily and quickly and that prepared microcapsules, with 93.3% encapsulation efficiency and 48.3% broken rate, had smooth surface, superior transparence and satisfied strength. Strength and flexibility of this kind of microcapsules could be further improved to decrease broken rate to 36.2% by using triethylenetetramine modified by glutaraldehyde.Electrophoretic particles were prepared by milling, with hansa yellow 10G as particles, with Span 80 as surfactant, and p-methoxyaniline as charge control agent. It was found that dispersibility of this kind of particles was 82.4% and electrophoretic mobility was -0.118cm2V-1s-1. Hansa yellow 10G was applied in EPD via above preparation methods, and it was found that electrophoresis was reversible and responding time was 1~3s at the condition of 30V/mm.更多还原