本文選題：聚乙二醇 + 定形相變材料　； 參考：《北京建筑大學(xué)》2017年碩士論文

【摘要】：隨著能源危機(jī)愈演愈烈,人們致力于開(kāi)發(fā)替代能源和新的儲(chǔ)能技術(shù)。相變儲(chǔ)能材料利用材料的相變潛熱進(jìn)行能量的儲(chǔ)存和釋放,控制周?chē)h(huán)境溫度的同時(shí)達(dá)到節(jié)約能源的目的,能夠解決能源在空間和時(shí)間上的不匹配問(wèn)題,因此成為大家關(guān)注的熱點(diǎn)。其中,定形復(fù)合相變儲(chǔ)能材料具有固-液相變儲(chǔ)能材料和固-固相變儲(chǔ)能材料的雙重優(yōu)點(diǎn),成為最具潛力的儲(chǔ)能材料之一。本文以聚乙二醇(PEG)為相變材料,選擇泡沫碳、硅藻土和蒙脫土作基體材料,采用物理共混法制備多個(gè)系列的聚乙二醇基定形相變儲(chǔ)熱材料。利用掃描電鏡(SEM)、X射線衍射(XRD)、N2吸附(BET)、紅外光譜(FTIR)對(duì)純PEG、基體材料以及定形復(fù)合相變材料進(jìn)行表征,通過(guò)差示掃描量熱(DSC)、熱重分析(TGA)對(duì)聚乙二醇基定形復(fù)合相變材料的熱性能進(jìn)行研究。研究結(jié)果表明,聚乙二醇/泡沫碳定形相變儲(chǔ)熱材料的定形能力為90wt%,而聚乙二醇/硅藻土和聚乙二醇/蒙脫土復(fù)合相變材料的定形能力分別為55wt%和60wt%,聚乙二醇與基體材料之間只存在簡(jiǎn)單的物理作用。聚乙二醇/泡沫碳復(fù)合相變材料的相變溫度隨聚乙二醇分子量的增加而增大,相變焓隨聚乙二醇分子量的增大先增后減,PEG分子量為4000的PEG/泡沫碳復(fù)合相變材料的熔化焓最大(168.5 J·g~（-1）);PEG4000/泡沫碳復(fù)合相變材料的相變溫度和相變焓隨PEG4000質(zhì)量分?jǐn)?shù)的增加而增大。55wt%PEG/硅藻土復(fù)合相變材料的凝固焓和熔化焓分別為76.93 J·g~（-1）和80.50 J·g~（-1）,凝固點(diǎn)和熔點(diǎn)分別為27.1℃和51.5℃,較純PEG的相變溫度變化很小(0.3℃和0.4℃)。60wt%PEG/蒙脫土復(fù)合相變材料的熔化焓為95.1 J·g~（-1）,聚乙二醇/蒙脫土復(fù)合相變材料的相變溫度與相變焓均隨PEG質(zhì)量分?jǐn)?shù)的增加而有所增大,但相變溫度低于聚乙二醇的。聚乙二醇基復(fù)合相變材料具有良好的熱循環(huán)性和熱穩(wěn)定性,經(jīng)200次熱循環(huán)后樣品仍能保持定形,相變溫度和相變焓基本不變,200℃以下樣品均無(wú)熱分解。
[Abstract]:As the energy crisis intensifies, people are devoting themselves to developing alternative energy sources and new energy storage technologies. Phase change energy storage materials use the latent heat of the materials to store and release energy, control the ambient temperature and achieve the goal of energy conservation, which can solve the problem of energy mismatch in space and time. Therefore becomes the hot spot which everybody pays attention to. Among them, the amorphous composite phase change energy storage material has the dual advantages of solid-liquid phase change energy storage material and solid-solid phase change energy storage material, so it has become one of the most potential energy storage materials. In this paper, polyethylene glycol (PEG) was used as phase change material, foam carbon, diatomite and montmorillonite were selected as matrix materials, and several series of polyethylene glycol based amorphous phase change thermal storage materials were prepared by physical blending method. The pure PEG, matrix materials and amorphous composite phase change materials were characterized by scanning electron microscopy (SEM), X ray diffraction (XRD) and X ray diffraction (XRD). The thermal properties of polyethylene glycol based composite phase change materials were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results show that The setting ability of polyethylene glycol / carbon foam phase change thermal storage material is 90 wt, while that of polyethylene glycol / diatomite and polyethylene glycol / montmorillonite composite phase change material is 55 t% and 60 wt respectively. There are simple physical effects. The phase transition temperature of polyethylene glycol / foamed carbon composite phase change material increases with the increase of molecular weight of polyethylene glycol. The maximum enthalpy of melting of PEG/ foam carbon composite phase change materials with PEG molecular weight of 4000 increases and then decreases with the increase of molecular weight of polyethylene glycol. The maximum enthalpy of melting of PEG4000 / PEG4000 / PEG4000 / carbon foam composite PCMs increases with the increase of PEG4000 mass fraction. The solidification enthalpy and melting enthalpy of PEG / diatomite composite phase change material were 76.93 J / g ~ (-1) and 80.50 J / g ~ (-1) respectively, the solidification point and melting point were 27.1 鈩，

本文編號(hào)：1891910