【作者】 张磊；

【导师】 李齐方； 陈广新；

【作者基本信息】 北京化工大学 ， 材料加工工程， 2009， 硕士

【摘要】 本文首先以合成的八乙烯基倍半硅氧烷（OVS）和烯丙基-七环戊基倍半硅氧烷（allyl-POSS）,单分散性的PS（聚苯乙烯）-b-PB（聚丁二烯）和PS（聚苯乙烯）-b-P₂VP（聚2乙烯基吡啶）两种嵌段共聚物为原料,采用溶液铸膜和旋转涂膜法,研究了不同聚合物溶液浓度、POSS添加浓度、溶剂场、热场等条件下,聚合物薄膜及倍半硅氧烷在水面、硅基底的自组装行为。TEM表明,通过甲苯、环己烷、THF不同溶剂处理,在溶剂对聚合物链段选择性及水面对聚合物膜的综合作用下,PS-b-PB可得到微球、网状、反相微球等结构多样的自组装微观形态。AFM和TEM表明,在硅基底上,PS-b-PB随溶液浓度不同,可形成双连续状、洋葱状、微球状、层状等多种微观结构,且随浓度增加相分离尺寸增大。POSS添加浓度不同,在聚合物薄膜中形成尺寸、形貌不一的结构,如分散颗粒、十字、立方晶型等。经溶剂场和热场处理,聚合物两相分离形貌均会发生变化。聚合物中的POSS,经溶剂处理,发生重结晶生长,尺寸增大,并向膜表面移动;经热场处理,尺寸不变,向膜内部移动;两种方式处理后POSS均偏向于分布在PB相中。TEM表明,在硅基底上,PS-b-P₂VP随成膜转速不同相分离结构不同。二氯甲烷处理时间不同,可使微相结构由微球状向花瓣状、连续层状转变。POSS/PS-b-P₂VP甲苯溶液涂膜,两种POSS均偏向于分布在P₂VP相中,经溶剂处理会重新结晶生长形成大聚集体。POSS/PS-b-P₂VP二氯甲烷溶液涂膜,得到PS-P₂VP层状连续相、PS柱状相点阵、POSS三相并存的微观结构,OVS形成300nm规则结晶体,allyl-POSS形成200nm的不规则聚集体。此外,本文以巯丙基三甲氧基硅烷为原料,在甲醇体系中进行水解缩合,在盐酸催化下合成得到笼型、无规、梯形等多种结构倍半硅氧烷的混合物;在四甲基氢氧化铵和苄基三甲基氢氧化铵碱性条件催化下,均可合成得到成分单一、纯净的巯基官能化笼型结构倍半硅氧烷,产率分别为46%和64%。利用FT-IR、13C-NMR、29Si-NMR、XRD和DSC等手段,对其结构和性质进行了表征。巯基笼型倍半硅氧烷具有较高的熔点352℃和分解温度530℃,巯基的存在使其可进一步应用于自组装领域。更多还原

【Abstract】 Octavinyl-POSS （OVS）, allyl-POSS, PS-b-PB and PS-b-P₂VP diblock copolymers with monodispersion were used as raw materials, self-assembly of polymer films and POSS on the surface of water and silicon wafer were investigated. The films were prepared by solution casting and spin coating. Different polymer solution concentration, POSS added concentration, solvents, thermal condition were all studied.Results of TEM showed that PS-b-PB film on the water exhibited varied self-assemble microstructure as micelle, network and reverse micelle after annealed in the saturated vapor of toluene, cyclohexane and THF, due to combined actions of selective solvent and water to polymer chains.Results of AFM and TEM showed that on silicon substrate, PS-b-PB formed different micro-structures of bicontinuous, onion, micelle and lamellar with the solution concentration changed, and phase separation also increased with the concentration. OVS formed scattered particle, cross and cubic crystalline in the polymer matrix with its addition amount. After both solvent and thermal annealing, phase morphology of PS-b-PB changed. OVS recrystallized, grew, and moved to the surface of film after solvent annealing, but after thermal annealing its size didn’t change, then moved to the surface of film. OVS preferred to locate in the PB domain after annealing.Results of TEM showed that on silicon substrate, PS-b-P₂VP formed different micro-phase separation with different spin speeds. Annealing time in CH₂Cl₂ could make structures change from micelle to petal shaped and lamellar. When spin coating with toluene, the two POSS were both primarily in the P₂VP micro domains, and they would recrystallize and grow to macro-aggregation after CH₂Cl₂ annealing. When spin coating with CH₂Cl₂, three phases of PS-P₂VP lamellar, PS cylindrical lattice and POSS coexisted. OVS formed 300nm squared crystal, and allyl-POSS formed 200nm irregular aggregation.Furthermore, （3-Mercaptopropyl） trimethoxysilane was hydrolyzed and condensed in the methanol solution. The results showed that cage, random and trapezoidal structures of silsesquioxane mixture were synthesized under the condition of hydrochloric acid catalyst. Mercaptopropyl polyhedral oligomeric silsesquioxane （POSS） were obtained both in the presence of alkaline catalyst Me₄NOH or （C₆H₅CH₂） Me₃NOH, and the production yields were 46% and 64 %. The products were characterized by FTIR, ¹³C-NMR, ²⁹Si-NMR, XRD and DSC. It had excellent thermal performance with high melting point 352℃and decomposition temperature 530℃.更多还原