电子墨水技术的研究进展

对当今世界上主流的5种电子墨水技术的原理做了概括性的介绍与评述.它们分别是微胶囊电泳、双色拧转球、胆甾型液晶、电湿技术和电致变色技术.     

单层基板涂覆式彩色胆甾型液晶显示

描述了新型超薄彩色胆甾型液晶显示器,该显示器的各个功能层是依次涂覆于一个柔性基板上的。首次采用共享电极驱动器驱动无源矩阵彩色的乳液基的显示器,该显示器是由三层包埋于聚合物基体中的胆甾型微滴层积而成。     

Color gamut of cholesteric liquid-crystal films and flakes by standard colorimetry

Despite angle dependence and polarization selectivity, the color of cholesteric liquid-crystal (CLC) polysiloxane films can be quantified by standard colorimetry. A new fractured form of the film called “flakes” makes it possible to use the Center of Gravity Color Mixing Principle to predict the chromaticity of CLC color mixtures. A complete color gamut can be produced by layering CLC films, mixing CLCs physico-chemically, and mixing CLC flakes. © 1998 John Wiley & Sons, Inc. Col Res Appl, 23, 210–220, 1998     

Studies on the effect of substitution degree on the liquid crystalline behavior of cyanoethyl chitosan

An alkali–chitosan method was employed to prepare cyanoethyl chitosan (CNCS) with different degrees of substitution (DS) from chitosan by controlling the reaction time. The effect of the DS (from 0.36 to 1.21) on the liquid crystalline behaviors of CNCS was investigated. The critical concentration and texture of CNCS liquid crystalline in dichloroacetic acid and formic acid showed no obvious dependence on the DS. However, increase of the DS could enhance the birefringence of liquid crystalline solutions under a polarized microscope, which implied improved liquid crystallinity. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 2057–2061, 2000     

含羧酸与胆甾基元的硅氧烷类聚合物的液晶性能

合成了液晶单体4-烯丙氧基苯甲酸胆甾醇酯(Mch)和单体4-十一烯酸苯甲酸(Mc),通过硅氢加成反应得到了系列侧链液晶聚合物P0~P5。通过差示扫描量热(DSC)、偏光显微镜(POM)、旋光分析等手段对聚合物的液晶性能和相行为进行了表征,结果表明,含羧基的单体Mc(P1~P5)与不含羧基的单体Mc(P0)的聚合物相比,玻璃化转变温度(Tg)、比旋光度和清亮点(Ti)均明显降低,但是没有改变原聚合物的胆甾相类型;随Mc在液晶聚合物中摩尔百分数的增加,Tg继续降低,而Ti升高。Mc的引入拓宽了液晶聚合物的介晶区间。     

含2种介晶基元的液晶弹性体合成与性能研究

合成了一种向列液晶单体（M1）和一种新型手液晶交联单体（M2）,与含氢聚硅氧烷（PM-HS）接枝共聚。交联剂的摩尔分数从0－20%,得到了一系列侧链液晶弹性体P1－P7。通过差式扫描量热仪（DSC）、偏光显微镜（POM）和X-射线分析等手段对聚合物的结构、液晶性能及热性能进行了表征。结果表明,聚合物P1为向列液晶聚合物,P2－P6为胆甾液晶弹性体,P7没有液晶性。随着交联单体M2摩尔分数在体系中的增加,聚合物的玻璃化转变温度（Tg）、清亮点（Ti）和介晶范围逐渐降低。     

胆甾醇润滑添加剂的摩擦噪声与胶合分析

在N15机械油中添加胆甾醇,用标准的立式万能摩擦磨损试验台实验分析了N15机械油、N15油机械 胆甾醇的摩擦磨损性能。针对磨合阶段、稳定磨损阶段、胶合失效与摩擦噪声进行分析。结果表明,在磨合阶段摩擦因数有较大变化,随后的稳定磨损阶段中摩擦因数变化减小;在摩擦副出现胶合失效前,摩擦副的摩擦因数急剧上升;N15机械油 1.7%胆甾醇的抗胶合性能较好,但N15机械油 0.106%胆甾醇的摩擦噪声特性较好;胆甾醇添加剂可以显著改善N15号机械油的抗胶合能力。     

Synthesis and properties of photochromic cholesteric liquid crystalline polysiloxane containing chiral mesogens and azobenzene photochromic groups

A series of novel thermotropic side‐chain liquid crystalline polymers(P₀–P₁₂) were synthesized by grafting copolymerization of mesogenic monomer cholesteryl undecylenate (M1) and photochromic monomer 4‐allyoxy‐4′‐nitroazobenzene (M2) on polymethylhydrosiloxane. The chemical structures of polymers were characterized by infrared (IR) and ultraviolet (UV) spectroscopy. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to measure the thermal properties of those polymers, and the mesogenic properties were characterized by polarized optical micrograph, DSC, wide‐angle X‐ray diffraction and small‐angle X‐ray scattering. The glass transition temperatures (T_gs) of the polymers increased from P₀ to P₄ and decreased from P₅ to P₁₂. The clearing point temperatures (T_is) of the polymers P₁–P₁₂ were lower than that of P₀, but increased from P₁ to P₄ and decreased from P₅ to P₁₂. They showed thermotropic liquid crystalline properties in a broad mesogenic region at temperatures >100°C. The polymers P₀–P₈ exhibited a cholesteric mesophase with oily streaks and lined texture, and polymers P₉–P₁₂ showed a chiral smectic mesogenic phase with a layered texture. All of the polymers were thermally stable to ～ 320°C. The UV‐induced trans–cis photoisomerization was investigated for the azo monomer and polymers P₈ and P₁₂. The solution of the azo monomer and liquid crystalline polymers P₈ and P₁₂ can undergo photoisomerization, and the environments of the azo group were responsible for the aforementioned photochemical process. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2155–2162, 2002