【作者】 王云明；

【导师】 张淑芬； 唐炳涛；

【作者基本信息】 大连理工大学 ， 应用化学， 2013， 博士

【摘要】 可见光占太阳辐射能的40%以上,但由于其低的热效应,难以直接被相变储能材料所利用,本论文针对此科学问题,设计合成了光热转换定形相变储能材料,即以色素(染料、碳材料)为太阳光吸收介质,以高热焓值的聚乙二醇单甲醚(MPEG)或聚乙二醇(PEG)为相变储能分子,构筑光热转换与相变储能功能于一体的功能材料,实现对太阳辐射中可见光的有效利用。论文通过对聚醚端羟基进行化学改性,引入环氧基或异氰酸酯基,得到可反应性聚醚；色素通过重氮化-偶合、氯磺化、缩合或自由基等化学反应,使其具有反应性或在有机溶剂中具有良好的分散性；再以化学键链接构筑聚醚型光热转换定形相变储能材料,主要包括交联型、缩聚高分子型和碳掺杂复合型三类光热转换定型相变储能材料,采用UV-Vis、FT-IR、1H-NMR和13C-NMR谱图对相变储能材料进行了结构鉴定。首先,将反应性聚乙二醇单甲醚及反应性染料接枝到多乙烯多胺上,得到多胺型光热转换有机固-液相变储能材料,保留部分可反应性氨基,以甲苯-2,4-二异氰酸酯(TDI)或三聚氯氰为交联剂,通过交联反应,得到交联定形相变储能材料,赋予材料定形相变储能性能及较强刚性的同时,实现了高的光热转换存储效率(对应单波段,q>0.94；可见光400～700nm,η>0.74)和高的储能密度(△H>100J/g)。以具有两个等反应活性基团(羟基、氨基)的染料和聚乙二醇为缩聚单体,利用TDI梯度反应活性,通过两步缩合法,获得嵌段缩聚型光热转换有机定形相变储能材料,赋予材料较好的柔韧性、成模性及拉丝性能,同时实现了高的光热转换存储效率(对应单波段,η>0.90；可见光400～700nm,η>0.76)、高的储能密度(最大储能密度高达142.9J/g)、定形相变储能等性能。将碳材料(碳黑、多壁碳纳米管或单壁碳纳米管)通过表面化学改性,使其具有良好的有机溶剂分散性,通过超声辅助方法,将表面改性的碳材料均匀的掺杂到定形相变储能材料中,得到碳基复合型光热转换定形相变储能材料,实现了对可见光的全波段吸收与转换(400～700nm,η>0.84),提高了有机定形相变储能材料的导热性能(单壁碳纳米管含量达到2%时,材料的导热效率提高了25.1%)。更多还原

【Abstract】 The visible light accounts for approximately40%of solar radiation, which almost cannot be directly or effectively applied by phase change materials due to low thermal efficiency. In the present thesis, in view of this scientific issue, novel organic photothermal conversion materials were designed and synthesized based on colorants and phase change materials. The colorants (dyes and carbon) in the photothermal conversion materials were used as a photon antenna that served as an effective "photon capturer and molecular heater" of light-to-heat conversion, and the phase change material stored heat energy by a phase transition with high energy storage density. The novel materials have some notable advantages, such as UV-Vis sunlight-harvesting, light-thermal conversion and thermal energy storage for the realization of the highly efficient utilization of solar radiation.In this thesis, epoxy group or an isocyanate group was introduced to the terminal hydroxyl group of polyether (polyethylene glycol monomethyl ether or polyethylene glycol) by chemical modification that obtained reactive polyether; the colorant was designed and synthesized or surface-modified by using the diazotization-coupling, chlorosulfonated condensation or radical reaction to obtain the colorant with reactive or excellent dispersion in organic solvents. Then the light-thermal conversion organic shape-stabilized phase-change materials were designed and synthesized by chemical bond, which mainly contained cross-linking shape-stabilized materials, polycondensation polymer shape-stabilized materials and carbon/phase change material (PCM) composites. These photothermal conversion materials were characterized by UV-Vis, FT-IR,’H-NMR and13C-NMR.Firstly, the reactive MPEG and the reactive dyes were grafted onto polyethylene polyamine to obtain the organic photothermal conversion solid-liquid phase change engergy storage materials with the remaining amine gruops. Using toluene-2,4-diisocyanate (TDI) and cyanuric chloride as crosslingking agents, the remaining reactive amino groups of the solid-liquid phase change engergy storage materials were cross-linked, and the cross-lingking shape-stabilized phase change materials were obtained. The materials have some notable advantages, such as shape-stabilized properties in phase change process and strong rigidity. Simultaneously, the materials have a high photothermal conversion and energy storage efficiency (single band,η>0.94; visible light400-700nm,η>0.74) and high energy storage density (△H>100J/g).Secondly, the dyes containing two reactive groups (hydroxyl or amino group) and PEG were conducted by TDI through a two-step polymerization process. Then, the linear polycondensation photothermal conversion materials were obtained, and the materials exhibited high strength and flexibility. Simultaneously, the materials have a high photothermal conversion and energy storage efficiency (single band, η>0.90; visible light400～700nm, η>0.76), high energy storage density (△Hmax=142.9J/g) and hape-stabilized phase change energy storage and so on.Finally, the surfaces of carbon materials (carbon black, multi-walled carbon nanotubes and single-walled carbon nanotubes) were modified by reacting them with4-nitrophenyldiazonium cations to obtain a uniform dispersion in organic solvents. The surface-modified carbon was successfully hybridized by using ultrasound in PCM, thereby obtaining novel carbon/PCM composites. The materials have some notable advantages, such as a full band absorption of sunlight (400～700nm, η>0.84), a high thermal conductivity as compared to pure organic materials (content of2%, the material thermal efficiency is improved by25.1%); Additionally, a preliminary study showed that carbon/PCM composites exhibited high strength and flexibility.更多还原