可逆热变色复配物热变色性及机理探讨：甲酚红—碱土金属离子—十六醇体系

合成了甲酚红－碱土金属离子－十六醇体系可逆热色复配物。用ＤＳＣ，ＵＶ及ＩＲ光谱对该体系的变色机理进行了探讨。结果表明：甲酚红与碱土金属结合后，低温时的醌式结构，高温为内酯式结构，通过改变金属离子及醇的用量，还可以组成多变色可逆热变材料。     

可逆热变色复配物变色机理的研究——相变与变色现象之间的关系

通过差热扫描仪及熔点测试研究了可逆变色复配物的发色机理。结果表明：复配物中溶剂对热变色温度，变以温度范围影响很大。     

孔雀石绿-硼酸体系热致变色材料的制备与性能研究

本文选用孔雀石绿为发色剂,硼酸为显色剂,并分别选取丙二酸、草酸作为溶剂。按一定比例混合并进行加热合成孔雀石绿-硼酸体系可逆热致变色材料。考察不同质量配比样品的变色性、可逆反应的复色时间以及不同溶剂与用量对热致变色材料性能的影响。结果表明,孔雀石绿-硼酸体系可逆热致变色材料的最佳溶剂为丙二酸。确定了孔雀石绿∶硼酸∶丙二酸复配物最佳质量配比为1∶100∶10。该复配物在67℃时,颜色由浅绿色变为米白色,整个变色过程色泽鲜艳,变色敏锐,复色时间短且可逆性良好。     

热敏黑可逆热致变色复配物及其微胶囊化研究

分别选用了二苯甲酮、苯甲酸苯酯和苄基苯基醚作为3组分可逆热致变色复配物的溶剂,选出变色较灵敏、对比度较高的苯甲酸苯酯复配物进行微胶囊包覆。结果表明溶剂与显色剂的作用力强度对热致变色复配物可逆变色性能有很大的影响,而通过微胶囊包覆的方法可以得到稳定性好、变色灵敏程度高、对比度强的可逆热致变色材料。     

TF-R1-脲醛树脂原位聚合法制备可逆热致变色微胶囊

以热(压)敏玫红TF-R1、双酚A、十六醇为原料,制备了TF-R1可逆热致变色复配物,然后以复配物为芯材、脲醛树脂为壁材制备了可逆热致变色微胶囊,探究了原料配比对复配物变色性能的影响、转速及SiO₂对芯材乳化液粒径的影响及反应条件对微胶囊成型的影响,并评价了微胶囊的变色性能及热稳定性。结果表明,最佳原料配比m(TF-R1)∶m(双酚A)∶m(十六醇)为1∶5∶60,复配物的温变区间为47.4～52.7℃;最佳转速为2 000 r·min^-1,加入适量SiO₂能够有效分散芯材乳化液;当n(尿素)∶n(甲醛)为2∶3时,脲醛树脂预聚体的性能最佳;在预聚体浓度为25%、芯壁比为1∶3.5、缩聚时间为2.75 h的最佳条件下,制备的微胶囊的温变区间为50.1～56.3℃,变色时间为70.7 s,复色时间为65.1 s,变色可逆性良好,灵敏度高。     

可逆热变色复配物热变色性及机理探讨:甲酚红—碱土金属离子—十六醇体系合成及热变色性

合成了甲酚红—碱土金属离子—十六醇体系可逆热变色复配物。用ＤＳＣ、ＵＶ 及ＩＲ光谱对该体系的变色机理进行了探讨。结果表明：甲酚红与碱土金属离子结合后,低温时为醌式结构,高温时为内酯式结构。通过改变金属离子及醇的用量,还可以组成多变色可逆热变色材料。     

一种可逆热致变色材料的制备及微胶囊化研究

以隐色染料结晶紫内酯、溶剂十六醇、显色剂对羟基苯甲酸苄酯为原料制备有机类可逆热致变色材料，并确定了隐色染料、显色剂和溶剂的最佳配比为1：3：30。在可逆热致变色材料中，溶剂主要决定可逆热致变色材料的变色温度，显色剂主要决定可逆热致变色材料颜色的深浅，隐色染料本身决定了可逆热致变色材料的颜色及隐定性等性能。微胶囊化结果表明，微胶囊产品能增强可逆热致变色材料的热稳定性，可增加材料的抗溶剂性，且材料不易流失。     

热致变色复配物显色剂筛选及变色性能研究

采用结晶紫内酯(CVL)为发色剂,十六醇(CA)为溶剂,焦性没食子酸(PA)和4-甲氧基苯酚(MP)为显色剂,所形成的复配物具有可逆热致变色性质。实验证明所形成的热致变色复配物的特征吸收波长为610 nm,复配物的蓝色强度用复配物的吸光度定量表示。当复配物中CVL质量确定,MP和CA按比例变化时,复配物的熔化温度和变色温度几乎不受组成影响。复配物变色温度低于其熔化温度。     

溴酚蓝-碱土金属离子-十八醇热变色复配物的制备及热变色性

以溴酚蓝 (BPB)、碱土金属离子为原料 ,十八醇为溶剂制备了标题复配物 ,反应时间为 2h ,反应温度为 1 1 5℃ ,产率约为 87%。当m(BPB)∶m(CaCl2 )∶m(十八醇 ) =1∶1∶2 5时 ,加热至 55℃左右 ,复配物由亮绿色变为黄色 ,冷却 2～ 3min又由黄色变为亮绿色。经过 50 0次左右的热变色实验 ,该复配物仍具有较好的变色可逆性及稳定的变色温度。UV -Vis、DSC测定结果表明 :热变色性是由于在低温及加热时 ,溴酚蓝与碱土金属离子形成的配合物发生配位 -解离过程 ,使溴酚蓝产生内酯环式与醌式两种结构的互变 ,引起紫外 -可见吸收光谱的最大吸收峰发生位移 ,从而引起颜色的变化。     

可逆热致变色复配物的制备及微胶囊化研究

可逆热致变色是指一种颜色受热升温时变为另一种颜色,冷却后又恢复为原来的颜色的现象。热致变色材料主要由电子给予体、电子接受体和溶剂性化合物3类物质组成。其中决定颜色的是电子给予体,决定显色深浅的是电子接受体．溶剂则决定变色温度。当电子给予体与电子接受体之间发生电子转移平衡反应时。表现为可逆热致变色现象目。国内在可逆热致变色材料研究方面报道较少,近年来,国内有关科研单位,如北京航空航天大学、中科院化学所等已研制出了几种可逆热致变色材料四。研究开发出具有灵敏度高、可逆性好、稳定性强、使用寿命长、合成工艺简单实用的有机可逆热致变色材料已是备受国内外关注的研究领域。 对可逆热致变色复配物进行微胶囊化包覆。对其变色性能没有明显影响,但这样可将热致变色复配物与外界隔离。减少外界物质对其变色性能的影响,同时可避免受热变色时组分材料的流失,较好地保持其变色性能等刚,这将大大促进此类可逆热致变色性材料在测量、电子、医疗等领域的应用。本试验对热敏玫红TF-R1可逆热致变色复配物的微胶囊化采用原位聚合法,其壁材选用脲醛树脂。     

示温材料的制备及示温原理

示温材料作为一种功能材料,在生产,生活等方面有着广阔的应用前景。论述了示温材料的制备、变色机理和应用,并展望了示温材料的发展趋势。     

可逆感温变色聚丙烯专用料的制备及性能

通过两步法制备可逆感温变色聚丙烯（PP）专用料,首先将乙烯-辛烯共聚物（POE）与可逆感温变色粉于微型双螺杆挤出机中挤出造粒制备色母料,然后将PP与色母料熔融共混挤出制备可逆感温变色PP专用料。探讨了色母料含量对PP专用料感温变色性能、力学性能、热学性能及微观形貌的影响。结果表明,利用POE与PP良好的相容性,实现了可逆感温变色粉在PP基体中均匀的分散,可逆感温变色PP专用料表现出优异的可逆感温变色性能和冲击性能。     

热致变色聚合物研究进展

热致变色聚合物具有成本低、易制备、易加工、易修饰、稳定性好等优势,已被应用到温度传感、智能窗、变色涂料、显示器、智能纺织品、防伪等多个领域.根据热致变色机理,总结了共轭聚合物、超分子聚合物、凝胶、光子晶体和液晶聚合物的最新研究进展,并对其变色机理及应用进行了概述及分类归纳.最后,提出了目前热致变色聚合物在应用中还存在的问题,并对未来该领域的研究方向作了展望.     

可逆热致变色材料

综述了热致变色材料的变色机理,变色性能及其应用范围,有15篇参考文献。     

可逆热致变色材料的变色机理及应用

本文介绍了热致变色材料的类别和发展趋势,着重介绍了可逆热致变色材料的变色机理及其应用。     

可逆示温材料的变色机理及应用进展

本文介绍了无机可逆示温材料和有机可逆示温材料的组成、特点以及热致变色机理等，简要阐述了无机、有机和液晶可逆示温材料在工业、农业、医药以及日常生活方面的应用，充分说明了可逆示温材料具有广阔的应用前景。     

Insight into color change of reversible thermochromic systems and their incorporation into textile coating

Dynamic color and phase change of chosen thermochromic systems were deeply investigated and their incorporation into polyurethane textile coating was developed. The colorimetric properties of three commercial reversible leuco dyes-based thermochromic pigments (TPs) with activation temperature at 38, 50, and 60°C were studied. Color change as a function of temperature was evaluated and colorimetric values were related to phase transition temperatures via differential scanning calorimetry (DSC) measurement. Light fastness of commercial TPs in polyurethane coating was determined by accelerated aging measurement and the color stability has been improved by using ultraviolet absorber (UVA). This research opens new possibilities for smart textiles, which is a very promising field in high-technology materials.     

Combined experimental and DFT study on high-temperature thermochromism of Co-doped LaCrO3 coating for thermal indicator

Noncontact temperature measurement using thermochromic materials is vital in the field of temperature indication, but the related mechanisms behind thermochromic behavior are diverse and high complexity, and the color-temperature correspondence is poorly explored. This paper systematically studied the thermochromic mechanisms and color-temperature correspondence in the cobalt-doped LaCrO₃ coatings via experiment and density functional theory study. The coatings appear reversible thermochromism from green to black with temperature and composition, functions from room temperature to 700°C. This thermochromism is attributed to the lattice expansion and bandgap reduction as the temperature increase, and a model of temperature effect bandgap was proposed. Meanwhile, the coating temperature can be inferred from the color change because the CIE chromaticity coordinate of the coating varies linearly with temperature, and the mean relative error of thermochromic measurements is 8.28%. Furthermore, the cobalt doped introduces impurity energy levels and enhances the interaction between photons and carriers, which reduce the bandgap and increase the absorption in the visible spectrum resulting in darker colors. This work provides a stable and efficient high-temperature thermochromic coating that has a wide thermochromic temperature range and clear color-temperature correspondence, which shows broad application prospects in the field of thermal indication at high temperatures.     

Thermochromic core–shell nanofibers fabricated by melt coaxial electrospinning

Microcapsule/nanocapsule and encapsulation techniques have great potential for devices of functional materials. Also, electrospinning has attracted great attention for the fabrication of microstructures and nanostructures. The fluidity after melting limits the application of phase‐transformation thermochromic materials. In this study, with the melt coaxial electrospinning technique, a phase‐transformation thermochromic material was encapsulated in poly(methyl methacrylate) nanofibers. A device of this phase‐transformation thermochromic material was realized. With a poly(methyl methacrylate) shell with good optical transmission and a thermoresponsive core made of crystal violet lactone, bisphenol A, and 1‐tetradecanol core, the fibers had good thermal energy management, fluorescent thermochromism, and reversibility. The fabrication of thermochromic core–shell nanofibers has further potential in the preparation of temperature sensors with good fluorescence signals and body‐temperature calefactive materials with intelligent thermal energy absorption, retention, and release. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Printed thermochromic displays

Thermochromic displays, which were evaluated in this study, combine printed electronics with the thermochromism phenomenon. Conductive lines printed on the reverse side and thermochromic printing ink printed on the front side of cardboard packaging form a thermochromic display that gives cardboard packaging additional value. Displays were printed on different printing materials, and thermochromic printing ink was deposited in one and two layers. In addition, half of the samples were varnished. The influence of the printing material, the thickness of the thermochromic printing ink layer, the varnish, the high temperature, and light fastness on the display's operability were all evaluated. It was clearly shown that the choice of printing material plays a crucial role in the display's operability. Moreover, high temperature and light fastness also have a significant influence, although the impact is negligible when the display is used at room temperature.