Surface Stability in Liquid-Crystalline Block Copolymers with Semifluorinated Monodendron Side Groups
Surface Stability in Liquid-Crystalline Block Copolymers with Semifluorinated Monodendron Side Groups
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DOI：
10.1021/ma992111s
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发表时间：
2000-07
期刊：
影响因子：
5.5
通讯作者：
M. Xiang;Xuefa Li;C. Ober;K. Char;J. Genzer;E. Sivaniah;E. Kramer;D. Fischer
中科院分区：
文献类型：
--
作者：
M. Xiang;Xuefa Li;C. Ober;K. Char;J. Genzer;E. Sivaniah;E. Kramer;D. Fischer
通过将第一代2-或3-臂单枝氯化物连接到羟基化的聚苯乙烯-b-1，2/3，4-异戊二烯上，合成了含半氟单枝侧基的嵌段共聚物。发展了一种收敛生长策略，利用一种可推广到高世代单树的方法来合成产量较高的单树类群。尽管体积庞大的单树侧基具有立体效应，但仍获得了高程度的附着。WAXS数据表明，合成的聚合物在室温下形成了近晶B中间相。近晶B-−各向同性转变的转变温度、中间相范围和转变热都受到侧基结构因素的影响，如柔性间隔基长度、介晶长度和单枝晶核。Zisman分析表明，合成的半氟化聚合物的临界表面张力低至∼8mN/m。聚合物膜在极性液体环境中的表面稳定性强烈依赖于...
Block copolymers with semifluorinated monodendron side groups were synthesized by attachment of a first generation 2- or 3-armed monodendron acid chloride to a hydroxylated poly(styrene-b-1,2/3,4-isoprene). A convergent growth strategy was developed to synthesize the monodendron groups in good yield using an approach that could be extended to higher generation monodendrons. High extents of attachment were achieved despite the steric effects of the bulky monodendron side groups. The resulting polymers formed a smectic B mesophase at room temperature as determined by WAXS data. The transition temperatures, mesophase range, and enthalpy of the smectic B−isotropic transition were all affected by side-group structural factors such as flexible spacer length, mesogen length, and monodendron core. The critical surface tensions of the resulting semifluorinated polymers were as low as ∼8 mN/m as determined by Zisman analysis. Surface stability of polymer films in a polar liquid environment was strongly dependent on...