热变色胆甾相液晶的制备及微囊化技术的研究

通过降低胆甾相混合液晶配方中胆甾烯基油烯基碳酸酯的含是及适当改变胆甾烯基氯的含量,获得了１０℃－５０℃范围内,变色温度梯度为１℃,变色范围从蓝色→绿色→红色的一系列胆甾相混合液晶。     

胆甾型液晶用于体温的精密测量

文中确定了能够在人体体温测量范围内变色的胆甾液晶混合物及其组成。通过改变混合体系中惰性添加剂的含量,获得在25℃~55℃范围内,变色温度精度为±(0.1~0.2)℃的一系列混合液晶组成。研究发现,混合液晶体系变色清亮点温度与添加剂加入量成良好的线性关系,线性相关系数最高可达到0.9991。     

纤维素及其衍生物的胆甾型液晶结构

综术了纤维毒素衍生物胆甾型溶致液晶结构的纤维素衍生物的复合物的结构研究的进展。纤维素衍生物能在多种溶剂中形成胆甾型溶致液晶，其液晶相具有多重织构特性，即它的多种织构的存在与外界条件如溶液的浓度、温度等有很大关系。在纤维素衍生物的胆甾型液晶溶液中还可观察到多种向错结构，含纤维素衍生物的高分子复合物的合成一方面使纤维素衍生物胆甾型液晶结构的研究进入了更微观的层次，另一方面其本身就具有潜在的应用前景。     

胆甾型侧链液晶共聚砜热转变温度的调节

采用壬烯－１与胆甾型液晶烯类单体，二氧化太进行自由基共聚合的方法来调节胆甾型侧链液晶共聚砜的热转变温度。研究内容包括：胆甾型侧链液晶共聚砜的合成、表征及性能测试。研究结果表明，该共聚砜的两个液晶转变温度均随其中壬烯－１单体单元组份含量的增加而降低。     

聚硅氧烷类手性偶氮液晶高分子的制备

合成了一种含胆甾醇基元的手性液晶单体4-烯丙氧基苯甲酰氧基异丙酰氧基胆甾基酯(M)和一种含偶氮基元的液晶单体4-烯丙氧基苯甲酰氧基异丙酰氧基偶氮苯甲酸乙酯(N),将它们与含氢聚硅氧烷接枝共聚,得到侧链手性偶氮液晶聚合物PA1~PA6。通过红外、核磁共振、旋光仪、偏光显微镜、差示扫描量热和X射线衍射等手段对所合成单体及聚合物的结构和液晶相行为进行了表征。结果表明,单体M具有胆甾相的油丝织构,单体N具有向列相的纹影织构,聚合物PA1~PA6呈现胆甾相的Grandjean织构,它们的热稳定性好,液晶区间宽达171~180℃之间。     

高分子胆甾相液晶盘状聚集体的结构分析

利用偏光显微镜,对乙基纤维素/二氯乙酸(EC/DCA)胆甾相液晶的织构进行了研究。当EC/DCA液晶溶液处于两相共存状态时,可以观察到一种典型的胆甾相液晶织构形式——盘状聚集体。结合有效偶极矩模型,推断了分子链在盘状聚集体中的排列方式及盘状聚集体的二维等速生长性质。     

多稳态显示用液晶材料的研究与开发进展

多稳态液晶材料是用手性液晶和宽温向列相液晶配制而成的胆甾相液晶材料。有关该材料方面的开发研究报道相对较少,日前在国内外尚无商品。只有少量胆甾相/向列相液晶材料样品出售,仅供研究与开发FMLCD技术使用。因此,为了适应FMLCD技术发展需要,推动我国在多稳态液晶显示领域的发展,加强在液晶材料市场的竞争能力,我们公司根据国家863和FMLCD技术要求,结合我们十多年开发与生产液晶材料的经验、知识与产品的积累及其总结出的配方经验理论,在现有的大△ε值、大△n值及普通的单体液晶材料的基础上,设计并合成了9种新宽温的、3种大△n值的单体液晶化合物和11种新型手     

胆甾相液晶技术应用于防伪

胆甾相液晶具有独特光学特性,不但在液晶显示器和医药方面获得广泛的应用,也在防伪技术行业有了新的拓展。日前,中国防伪技术协会在北京组织召开了技术评审会,对日本发条株式会社的＂胆甾相液晶防伪标识＂进行了技术评审。     

含酒石酸基元的液晶单体及其聚合物的合成与表征

合成了一种以酒石酸为中心的新型工字型液晶单体2,3-二乙酰氧基-1,4-丁二酸对烯丙氧基苯甲酸对苯二酚酯(M1),将其与手性液晶单体4-烯丙氧基苯甲酸胆甾醇酯(M2)共聚,得到侧链液晶聚合物P1～P8。通过红外光谱(FT-IR)、核磁共振(1H-NMR)、偏光显微镜(POM)、差示扫描量热分析(DSC)和X射线衍射(XRD)等手段对所获单体及聚合物的结构和液晶相行为进行了表征。结果表明,液晶单体M1具有近晶相扇形、纹影织构,手性单体M2具有胆甾相油丝织构。聚合物P1～P8出现胆甾相的Grandjean织构,随着单体M1含量的增加,聚合物P1～P8的Tg呈上升趋势,液晶区间变窄。     

含氟与胆甾醇基液晶聚合物的合成与表征

将一种含胆甾醇基液晶单体、一种含氟单体与聚甲基含氢硅氧烷接枝共聚合成了一系列液晶聚合物。采用红外光谱(FT-IR)、核磁共振(1H-NMR)、偏光显微镜(POM)、X射线衍射(WXRD)与差示扫描量热分析(DSC)等测试手段,对单体及聚合物进行了结构与性能的表征。随着含氟基团组分含量逐渐增加,该系列液晶聚合物的玻璃化转变温度与清亮点都呈现降低趋势,并且液晶相由胆甾相转变为近晶相。由于含氟部分和聚合物中的碳氢部分极难相容,形成层状聚集,从而使胆甾相受到抑制,有利于近晶相的形成和稳定。     

氯甲酸胆固醇酯引发的MMA原子转移自由基聚合反应

首次报道以氯甲酸胆固醇酯(CC)为引发剂,氯化亚铜和自制MA5-DETA为催化刺进行甲基丙烯酸甲酯(MMA)的原子转移自由基聚合(ATRP)反应。研究发现,单体转化率与反应时间、产物分子量及分子量分布呈线性关系。在转化率不太高时所得聚合物的分子量分布较窄(1．5以下),反应具有活性聚合特征。虽然引发剂的引发效率较低,但是这不失为制备胆甾型液晶材料的一种新方法,且能说明酰基卤化物也可作为ATRP的引岩剂．     

DCC／DMAP法合成二茂铁基苯甲酸胆甾醇酯

倒重氮法合成两类二茂铁基苯甲酸，继而研究以N，N-二环己基碳二亚胺（DCC）作脱水剂，用4-二甲胺基吡啶（DMAP）作除水促进剂，胆甾醇与间、对-二茂铁苯甲酸反应合成液晶材料间、对-二茂铁基苯甲酸胆甾醇酯的方法。研究结果表明，该方法反应条件比较温和，用DMAP作除水促进剂时，胆甾醇酯产率比较高。高效酰化催化剂法是十分有效的酰化方法，在合成胆甾醇酯液晶中可较大幅度地提高产品的产率与纯度，简化操作，降低反应毒性。     

肉桂酸胆甾醇酯光二聚体液晶的制备及其性能的研究

首先合成了光二聚型肉桂酸胆甾醇酯，通过光二聚法制备了含强刚性结构的二苯基环丁烷二羧酸二胆甾醇酯液晶分子。研究发现：通过骤冷可得到玻璃态胆甾相液晶，并可以反复熔融和冷却实现可逆的彩色显示。     

Novel application of Eudragit RL and cholesteryl oleyl carbonate to thermo-sensitive drug delivery system

The Eudragit RL 100 and propylene glycol (PG) membranes with and without cholesteryl oleyl carbonate (COC) were prepared by the solvent casting method to pioneer a novel application of a thermo-sensitive drug delivery system. After that, the properties of these membranes were investigated by thermal, scanning, and porosity studies. Drug permeation studies through all membranes were carried out using salbuthamol sulphate (SBS) at constant temperatures (25°C and 37°C), respectively. The permeability of SBS through the membranes with COC has been shown to be a discontinuous function of temperature, that is, their permeability increased steeply above the phase transition temperature (37°C) of the COC. The thermo-sensitive permeation mechanism for the membranes might be based on the structure change of the membranes caused by the phase transition, so that the membranes could absorb more water. Considering the high biological safety of Eudragit RL 100 and PG membranes with and without COC might be used to develop a novel thermo-sensitive drug delivery system.     

Kinetics of swelling/shrinking rearrangement of a self-aggregated nanohydrogel at solid/liquid interfaces

The hydrogel nanoparticles (nanohydrogels) have great potentials in numerous biomedical applications. Biomembrane-mimetic self-assemble nanohydrogel MC _n (n repeated 2-methacryloyloyloxyethyl phosphoryl choline grafted cholesteryl group-bearing pullulan) was designed. In order to mimic the interfacial responses of fibrinogen at the hydrophobic/hydrophilic surfaces, MC _n molecules were controlled by the chain length of the decorated MPC in term(s) of n?=?0, 6.2, 14.3 and 180, respectively. The dynamic rearrangements of MC _n hydrogel molecular layer on the hydrophobic highly ordered pyrolytic graphite surface were observed by the atomic force microscopy. The results showed that there were biphasic transitions at the liquid/solid interfaces from the initial solute state to metastable state to the equilibrium state. The length of MPC branches, n, governed the changes of layer thickness to the equilibrium state appearing as swelling or shrinking. The time evolution of the thickness was fitted by a single exponential model, and the kinetics parameters of surface rearrangements to the equilibrium state were obtained.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……