光热敏微胶囊材料的囊芯固化特性研究

光热敏微胶囊材料可作为新型的高分辨率光信息记录媒质;本文在利用界面聚合法制备平均粒径为0.4μm的光热敏微胶囊基础上,获得了囊芯的凝胶率及影像密度随曝光时间的变化。结果表明囊芯光敏功能物质的凝胶率随曝光时间增长逐渐增大,显影密度随曝光时间增加而降低;不同曝光时间下微胶囊囊芯光固化程度不同是导致影像密度出现反差的直接原因。     

光热敏微胶囊材料光固化影像密度特性研究

光热敏微胶囊材料可作为新型非银盐信息记录媒质,其囊芯光敏反应是实现光信息记录的关键。本文利用傅立叶变换红外光谱技术,通过监测囊芯TMPTA单体的C=C双键在1650-1626cm-1处特征吸收峰随曝光时间的变化,发现在紫外光照射下,TMPTA分子C=C双键在光引发剂自由基作用下发生交联聚合而引起微胶囊囊芯固化,随曝光时间增长,囊芯固化程度表现为先快速增加,再到曝光20s后基本达到稳定。显影密度检测表明,光热敏微胶囊内部固化程度直接决定了后续热显影的影像密度,进而在不同曝光时间下形成了影像密度反差。     

光敏涂料

一、概述: 光敏涂料是以感光树脂为主要成膜物质的一种特种涂料,它属于新型光敏材料之一。(光敏材料的应用一般可分为光敏塑料、光敏涂料、光敏粘合剂三大类)由于光敏涂料不仅在紫外光照射作用下能实现快速固化成膜,而且还具备某些能光刻各种精密图形等独特的性能,因此这种涂料被人们日益引起重视。在国外近年来进行了大量的研究已在     

光敏变色材料

光敏变色材料在美国、西德、日本等国已做了大量工作,得到一定的发展。所谓光敏变色材料即是由于光照,随着吸收光谱的变化,该材料的颜色或其光的吸收特性发生动态变化,且颜色能发生可逆变化的物质。这些材料主要用于光学记录介质、信息显示、光学贮存、光学保护以及装饰等方面,应用范围很广。本文对各类有机光敏变色材料及其变色机理、合成途径、应用领域等作扼要介绍。     

光热敏微胶囊信息材料显影密度随囊壁厚度的变化

主要研究光热敏微胶囊信息记录材料的热显影特性。在保证充分反应的前提下,调整囊壁材料D110的用量,制得囊壁厚度不同的光热敏微胶囊。将不同壁厚的微胶囊与同一显色剂均匀混合,涂布成片。通过不同壁厚微胶囊涂片的灰雾值比较,得到了完全包裹时囊壁材料的最低用量。在相同的显影条件下测得不同的热显影密度,得到显影密度随加入囊壁材料用量的变化趋势。     

MUF/石蜡相变储能材料的制备及其表征

以液体石蜡为囊芯材料,三聚氰胺尿素甲醛树脂(MUF)为囊壁材料,采用原位聚合法制备MUF/石蜡微胶囊,探讨了反应温度和搅拌速度对MUF/石蜡微胶囊的影响。随着反应温度增高,微胶囊囊壁厚度增大,调节微胶囊搅拌速度可以控制微胶囊粒径。采用光学显微镜观察了微胶囊的形成过程,采用扫描电子显微镜和红外光谱表征了微胶囊表面形貌与化学结构,采用DSC分析其储热性能特征,结果表明MUF/石蜡微胶囊强度好,封闭性能好,储能性能好,可以作为相变储能材料进行应用研究。     

复凝聚法制备热变色色素微胶囊的研究

有机热变色复配物通常以微胶囊形式应用。本文研究了以明胶—阿拉伯树胶为囊壁的复凝聚法微胶囊化工艺。研究了影响微胶囊粒度及状态的因素。选用优化的工艺条件可制得平均粒径为５μ且包囊很好的以明胶为囊壁材料的微胶囊。     

复凝聚法制备热变色色素微胶囊的研究

有机热变色复配物通常以微胶囊形式应用。本文研究了以明胶－阿拉伯树胶为囊壁的复凝聚法微胶囊化工艺。研究了影响微胶囊粒度及状态的因素，选用优化的工艺条件可制得平均粒径为５μ且包囊很好的以明胶为囊壁材料的微胶囊。     

包裹硅酸钠的微胶囊自修复混凝土在不同修复剂下的修复性能

以九水硅酸钠为主要囊芯材料、乙基纤维素为囊壁材料制备了一种粒径为1 000～1 250 μm的自修复混凝土微胶囊.以三种氟硅酸盐为固化剂,探究在不同固化剂,不同微胶囊掺量下水泥砂浆的基本力学性能及自修复性能.结果 表明以氟硅酸钠为固化剂的微胶囊自修复水泥砂浆具有明显的自修复性能,且当微胶囊掺量为1％时对水泥砂浆的抗压强度有一定的增强作用.     

“核-壳”微胶囊改性碳纤维树脂基摩擦材料的性能研究

为了进一步提高树脂基复合材料在使用中的安全性和使用寿命,本文引入一种具有自修复性能的微胶囊,以修复粘结产生的微裂纹,从而改善材料的摩擦学性能。通过界面聚合法,以脲醛树脂为囊壁,环氧树脂为囊芯材料,制备微胶囊,并分析乳化剂的用量对微胶囊产率和囊芯率的影响;采用SEM观察微胶囊的微观形貌、FTIR表征化学组分;研究微胶囊的加入对复合材料摩擦磨损性能的影响规律。实验结果表明,制备微胶囊直径为40～60μm、壁厚为2～3μm的粗糙球体;乳化剂的优化用量为14mmol时,微胶囊的产率为67.5%,囊芯率为64.88%;当微胶囊的添加量为5%时,复合材料的平均摩擦系数为0.141,比未添加时提高了19%,磨损率明显降低了40%,表明微胶囊技术能够较好地改善复合材料的摩擦性能。     

关于微胶囊型热记录材料的研究(I)

介绍了由微胶囊化的碱性隐色染料和酚显色剂构成的热记录材料的热记录特性及微胶囊壁和其他成分的热特性。由于酚系显色剂和微胶囊壁的相互作用,酚系显色剂的熔化温度 Tm及微胶囊的玻璃化温度 Tg大大降低。最低的显色温度和降低了的 Tm和 Tg两者中较高的温度一致。     

热敏记录材料中显色剂微胶囊对显色性能的影响

本文主要论述了在一种热敏记录材料中,为降低灰雾,微胶囊包裹技术在显色剂中的应用以及微胶囊包裹显色剂对整体显色性能的影响;并得到了微胶囊包裹显色剂合适的壁材用量。     

Reversibly thermochromic micro-fibres by coaxial electrospinning

A ‘solvent facilitated’ coaxial electrospinning process was used to produce reversible narrow temperature gap thermochromic, core-shell fibres. A thermochromic composite composed of crystal violet lactone (the leuco dye), bisphenol A (the developer) and 1-dodecanol (the phase-change solvent) was entrained as core material inside poly(methyl methacrylate) shells. A mutual core and shell solvent (chloroform) was used to obtain low interfacial tension between the core and shell spinning solutions. This enabled room temperature entrainment of the low molecular weight, low viscosity core fluid. In order to minimize the effect of light scattering and subsequently produce fibres with visible colour transitions, the fibres were produced with external diameters of 3-8 μm and core diameters of 1.7-5.7 μm. In order to produce core-shell fibres with repeated, reversibly thermochromic behaviour and a stable colour developed state, it was necessary to entrain a dye composite that contained an excess developer, essentially making this composite non-thermochromic prior to entrainment. The fibres were analyzed using SEM and DSC.     

Fluorescent photoimaging with polymers having protected quinizarin dye precursors by a dry process based on chemical amplification

Styrene monomers, possessing three kinds of protected quinizarin (Qz) dye precursors such as tBOC, acetyl and tosyl groups, have been prepared and copolymerized with MMA in high yields to obtain protected-Qz precursor polymers (pr-QzP). Thermal and photoinduced acidolytic deprotection behaviors were investigated to confirm the regeneration of the Qz moieties in the polymer films by thermal and spectral analyses. Lithographic fluorescent photoimaging on spin-cast films of pr-QzP containing a photoacid generator resulted in high resolution and sensitivity by a dry process based on chemical amplification. In the dry lithography process, finely resolved sub-0.4-micrometer fluorescent patterns were delineated on the thin precursor polymer films without using a developer.     

Preparation of poly (acrylic acid) containing core‐shell type resin for removal of basic dyes

BACKGROUND: A core‐shell type carboxylic acid modified resin was prepared and dye sorption characteristics of the resin were investigated. The resulting grafted resin material has been shown to be an efficient sorbent for removal of basic dyes from water as a result of the carboxylic acid group's affinity towards basic dye molecules. RESULTS: The resin was characterized using Fourier transform infrared spectroscopy (FT‐IR) and titrimetric methods. The basic dyes (methylene blue and crystal violet) were removed by contacting the swollen resin with aqueous dye solutions at room temperature. The adsorption capacities of resin were determined by colorimetric analysis of the residual dye content in the adsorption medium, which gave capacities for methylene blue and crystal violet of 300 and 250 mg g^?1 resin, respectively. The prepared resin is also able to remove basic dyes completely from dilute aqueous dye solutions. Batch kinetic sorption experiments determined that a pseudo‐second‐order rate kinetic model was applicable. CONCLUSION: Flexibility of the polymer side chains is expected to provide pseudo‐homogeneous reaction conditions and easy accessibility of the functional groups involved. The adsorbents are expected to have the advantage of mobility of the grafted chains in the removal of basic dyes from aqueous mixtures. The resin has potential as an adsorbent for removal of basic dyes for use over a wide pH range. Copyright © 2011 Society of Chemical Industry     

新型铁碳复合材料合成及其对染料废水脱色性能的试验研究

试验以煤粉还原菱铁矿,通过两段焙烧工艺制备了新型铁碳复合颗粒材料(F/C材料),并研究利用其微电解作用处理染料废水的条件及影响因素。主要研究了材料粒径、染料废水初始pH、温度和共存离子等对直接青莲染料脱色性能的影响。结果表明,相比传统的铁碳分离微电解材料,F/C材料对染料废水具有更好的脱色性能。材料投加量为0.3 g/L,粒径为0.18～0.25 mm,25℃下反应8 h后,质量浓度100 mg/L直接青莲废水的染料去除率可达90%,且共存离子影响较小;柱试验表明,制备的F/C材料对该染料的处理量为15.7 mg/g。     

Genetic targeting of individual cells with a voltage-sensitive dye through enzymatic activation of membrane binding

Optical recording of the electrical activity of individual neurons in culture or in a tissue requires cell-selective staining with a fluorescent voltage-sensitive dye. In a proof-of-principle experiment, we implement a novel approach to genetically targeted staining. The method relies on a water-soluble precursor dye and an overexpressed cell-surface enzyme that transforms the precursor into a hydrophobic dye that binds to the targeted cell. We fused an alkaline phosphatase to a specifically designed general-purpose membrane anchor, and the fusion protein was expressed on the surface of HEK293 cells, as was corroborated by immuno- and histochemical staining. We next synthesised an amphiphilic hemicyanine dye containing two enzymatically cleavable phosphate groups at its hydrocarbon tails. When the phosphate groups were removed, the binding to membranes was enhanced by a factor of a thousand, as shown by titration with lipid vesicles. We observed selective staining of enzymatically active cells by fluorescence microscopy in a mixed population of phosphatase-transfected and untransfected HEK293 cells. The critical parameters of enzyme-induced cell-selective staining were elucidated by a simple kinetic model to guide further developments of the method.     

Synthesis of an anthraquinonoid disperse reactive dye based on a ligand-free Ullmann reaction

A new anthraquinonoid disperse reactive dye containing a dichlorotriazine reactive group was successfully synthesised on the basis of the Ullmann reaction in a ligand-free system by employing a copper(i ) iodide as catalyst, in combination with a subsequent condensation reaction. The parameters of the cross-coupling reaction between 1-chloroanthraquinone and 2,5-diaminotoluene sulphate were investigated and optimised, such as the molar ratio of the reactants, the dosage of potassium carbonate and copper(i ) iodide, the reaction temperature, and the reaction time. The results demonstrate that the dosage of potassium carbonate and the reaction time had significant impacts on the yield of the dye precursor, and an optimum synthesis process was also recommended. Moreover, the achieved dye was successfully characterised and confirmed from chemical structure and colour characteristics by employing Fourier transform infrared analysis, nuclear magnetic resonance spectroscopy, UV-vis absorption spectroscopy, elemental analysis, and liquid chromatography–mass spectrometry (LC-MS). Furthermore, a successful application of the obtained dye was achieved, with satisfactory coloration properties on silk and wool.     

高铁酸钾氧化脱色三苯甲烷染料废水

采用高铁酸钾对水溶性三苯甲烷染料结晶紫和碱性品红废水进行氧化脱色研究。考察了高铁酸钾投加量、反应温度和染料浓度对脱色率的影响。结果表明,高铁酸钾能够有效去除染料废水中的色度,投加量和反应温度均存在最佳值。当结晶紫和碱性品红废水的质量浓度低于50mg/L时,脱色率几乎不受染料浓度的影响。2种三苯甲烷染料相比较,碱性品红比结晶紫更容易被氧化降解。     

Basic functionalization of polyethylene in the melt

The production of a polymer containing basic functional groups via the reactive processing of polyethylene was investigated. Grafting of dimethylamino ethyl methacrylate, DMAEMA, to linear low-density polyethylene in the melt was carried out, and the effects of initiator type, feed composition, and reaction time and temperature were studied. The extent of grafting was determined by Fourier transform infrared and ¹H nuclear magnetic resonance spectroscopy, and the degree of cross-linking was observed by measuring the products' melt indices. Thermal stability of the product was investigated using differential scanning calorimetry. Materials containing up to 3 wt% of grafted DMAEMA were prepared. The choice of appropriate feed compositions and reaction conditions allows the production of a material containing the maximum amount of grafted DMAEMA, while minimizing cross-linking. The grafted polyethylene produced under these conditions is more stable than the starting material, suggesting an antioxidant effect of the grafted moieties. The functional polymer produced should be of interest for the preparation of polymer blends with acidic polymers by virtue of the miscibility enhancement that could occur as compared with the hydrocarbon precursor.