石膏载体定形相变材料的制备及其热性能

制备了以石膏作载体、石蜡作相变材料的定形相变材料(复合石膏板)。实验证明表面活性剂硬脂酸钠可有效提高石膏板吸收石蜡的质量比,差示扫描量热结果显示复合定形相变材料中石蜡的相变温度、峰顶温度降低,相变吸热量与相变蜡在复合材料中的质量成正比。     

PEG/SiO2定形相变材料在沥青及水泥环境中应用的可行性

以聚乙二醇/二氧化硅(PEG/SiO2)定形相变材料与沥青、水泥为原料,采用物理共混法制备出沥青或水泥复合定形相变材料.利用综合热分析仪(TG-DSC)测试复合相变材料的储热性能及热稳定性,通过FT-IR对复合相变材料的兼容性进行了表征,探讨PEG/SiO2定形相变材料在沥青、水泥环境中应用的可行性.试验表明,复合定形相变材料具有较高的相变焓,良好的热稳定性和兼容性.将PEG/SiO2定形相变材料应用于公路工程中,可实现太阳能量转换与储存,主动调节路面的使用温度,并在高温条件下可有效降低路表温度,减少温度对路面的病害,缓解城市热岛效应,改善人居环境,其应用前景广阔.     

定形相变材料的制备与性能研究

采用本体聚合法分别制备了以癸酸、硬脂酸及两者的共熔"合金"作为蓄热介质,PMMA作基体的定形相变蓄热材料.用DSC、TGA、FT-IR、SEM等测试方法对蓄热材料的热性能、表面形态及相变材料与基体的相容性等进行了研究,结果表明,制备的定形相变蓄热材料具有合适的相变温度和较高的相变潜热,相交过程无液体泄露,相变材料在基体中分散均匀,两者相容性好,热性能稳定,可以应用于建筑节能和太阳能利用等领域.     

石膏-水泥-粉煤灰系复合胶凝材料的研究

对石膏、水泥及粉煤灰等胶凝材料进行复合改性研究，结果表明，石膏-水泥-粉煤灰系复合胶凝材料在适宜的配比下，可以制作耐水性好、强度高以及干燥收缩率低的新型墙体材料。通过对试件硬化体微观晶体形貌的观测研究，分析了石膏-水泥-粉煤灰系复合胶凝材料耐水性能改善的机理。     

改性磷石膏矿渣水泥在混凝土和路基材料中的应用研究

利用生石灰对磷石膏进行改性,得到改性磷石膏,将改性磷石膏、矿渣粉、水泥按一定比例混合均匀,通过粉磨制得改性磷石膏矿渣水泥,分析研究了改性磷石膏矿渣水泥的性能及改性磷石膏矿渣水泥在混凝土和路基材料中应用的可行性.结果表明:与未改性磷石膏相比,利用改性磷石膏制得的水泥早期强度有所提高;以改性磷石膏矿渣水泥为胶凝材料的混凝土...     

储能保温砂浆的试验研究

通过硬脂酸丁酯与十八烷基蜡复合制备相变温度点为22.07℃,相变潜热值为34.82 J/g的复合相变材料(石蜡含量40%)通过喷雾干燥法,把复合相变材料包裹在膨胀珍珠岩中,制备了复合相变颗粒;辅以水泥、可再分散如胶粉等制备了相变储能保温砂浆最后测试了其热工性能。     

脂肪酸/无机纳米颗粒基定形相变材料的制备与热性能

以工业水玻璃为纳米SiO2前驱物,以癸酸(CA)和月桂酸(LA)二元低共熔酸为相变芯材,在表面活性剂的参与下,采用溶胶-凝胶法一步制备出纳米级复合定形相变蓄热材料.利用透射电子显微镜,扫描电子显微镜,傅里叶红外光谱仪,方差扫描量热法和热重分析等测试技术对此定形相变蓄热材料的结构和性能进行分析,并采用瞬态热线法测量了其导热系数.结果表明:相变芯材在吸热熔化后不会产生流动和渗漏;复合相变材料中脂肪酸含量(质量分数)为46％,具有良好的相变蓄热性能(相变温度19.57℃,相变潜热71.28 J/g)和热稳定性;复合相变材料导热系数为0.178 W/(m·K),可作为一种良好的隔热、保温建筑材料.     

CA-MA/白炭黑相变储能砂浆的性能研究

以癸酸(CA)-肉豆蔻酸(MA)为储能基元材料,以白炭黑为中间体,采用真空吸附法制备CA-MA/白炭黑相变定形材料。实验按照水泥∶砂=1∶2的比例混合,同时为了增加热导率添加CA-MA/白炭黑定形相变储能材料的4%,并添加膨胀石墨防止相变材料的泄漏。测试砂浆的表观密度、抗压强度、热学性能,评价砂浆的相变储能效果,结果表示所制备的砂浆满足相变储能砂浆的要求。     

石蜡/改性粉煤灰定形相变材料的制备及热性能研究

以石蜡（PA）为相变芯材，以经酸浸法处理的改性粉煤灰（mFA）为封装基体，采用真空浸渍工艺制备PA/mFA定形相变材料。通过熔融泄漏测试、FT-IR、DSC、蓄放热性能试验研究了PA/mFA定形相变材料的化学相容性、相变热物性等。结果表明，m(PA):m(mFA)=1∶4时，PA/mFA定形相变材料基本无泄漏，PA与mFA为物理掺混；PA/mFA定形相变材料的相变温度为22.6℃，符合人体舒适温度，相变潜热较高，为41.3 J/g;PA/mFA定形相变材料熔化和凝固过程中温度变化均滞后于环境温度变化。     

脱硫石膏与水泥基材料相容性试验研究

在将脱硫石膏用于现浇墙体材料时,存在脱硫石膏与水泥基材料相容性技术问题。为了解决这一问题,本文采用有机高分子耐腐蚀胶黏剂和聚合物改性砂浆2种方案,确保脱硫石膏与水泥基材料长期共同工作。结果表明：使用界面剂和聚合物砂浆,4个月龄期内,脱硫石膏与水泥基材料的粘结强度持续增长：经过1年时间的长期观察。脱硫石膏与水泥基材料大面积薄层粘结良好。     

聚合物砂浆与脱硫建筑石膏粘结性能的研究

研究了聚合物砂浆与脱硫建筑石膏的粘结性能及干湿循环对粘结强度的影响,观察了聚合物砂浆与脱硫石膏的大面积长期粘结可靠性,并分析了粘结机理.结果表明,掺加5％聚合物的水泥砂浆与脱硫石膏粘结强度高、受干湿循环影响小、粘结牢固可靠.聚合物改善了水泥砂浆的微观结构,使粘结强度提高的同时,水泥砂浆耐石膏腐蚀性也大幅度提高,从而保证粘结耐久性.     

A novel montmorillonite-based composite phase change material and its applications in thermal storage building materials

A novel composite phase change material (PCM) was prepared by blending an organic PCM with an organic-modified montmorillonite. The thermal characteristics of the composite PCM were close to those of the pure PCM, and 1500 times heating–cooling cycles test showed that the composite PCM had good performance stability. Compared with the pure PCM, the composite PCM exhibited higher heat transfer rate owing to the combination with montmorillonite. The composite PCM had a good compatibility with gypsum powders, and the composite gypsum boards prepared had a function of cutting down energy consumption by decreasing the frequency of internal air temperature swings.     

Preparation and properties of gypsum-based heat storage and preservation material

The paraffin/expanded perlite shape-stabilized phase change material (PCM) was prepared by absorbing paraffin into pores of expanded perlite with vacuum adsorption method (VA method). The gypsum-based heat storage and preservation material was prepared by mixing the prepared paraffin/expanded perlite shape-stabilized PCM and gypsum. Scanning electron microscopy (SEM) was used to investigate the influence of the VA method and free adsorption method (FA method) on the microstructure of the paraffin/expanded perlite PCM. Differential scanning calorimetry (DSC) and exudation experiment were used to test the thermal property and shape-stability of the paraffin/expanded perlite PCM, respectively. The thermal conductivity, bending strength and compressive strength were also tested. The results showed that paraffin was uniformly distributed in pores of expanded perlite in the paraffin/expanded perlite PCM prepared with the VA method. The paraffin/expanded perlite PCM had satisfied shape-stability. The thermal conductivity of gypsum was decreased by addition of the paraffin/expanded perlite PCM. The adsorption amount of paraffin had little effect on the bending strength and compressive strength of the gypsum-based heat storage and preservation material.     

纤维石膏板应用于外墙的材料耐久性能研究

以石膏替代传统墙体材料 ,采用工厂预制成大型墙板的方式 ,在工业、民用建筑中用作各种承重及非承重外墙 ,是近年来广大科研工作者正在探索的课题 .笔者着重介绍了以石膏为基材 ,加入玻璃纤维对石膏强度的影响 ,加入水泥和外加剂对改善石膏软化系数和抗冻性的影响 .相关实验表明 :经过改性后的石膏可以用做外墙材料     

地板采暖系统用复合相变砂浆填充材料研究

阐述了相变砂浆作为填充层材料在地板采暖中应用的意义,采用溶胶-凝胶法制备了以二氧化硅为载体的复合有机相变颗粒材料,配制了相变石膏砂浆.利用地板采暖试验间进行了相变砂浆和普通砂浆的地板采暖试验,以验证相变砂浆地板采暖系统的蓄放热性能,并对地板表面和室内的温度影响进行了试验分析.通过试验验证了新型相变砂浆作为填充层材料应用到地板采暖是切实可行的,在较好改善室内温度环境的同时降低了地板采暖系统的荷载和厚度.     

Experimental study and evaluation of latent heat storage in phase change materials wallboards

Phase change materials (PCM) can be applied in building envelops to conserve heat energy. Wallboards incorporated with PCM can automatically absorb indoor redundant heat, which can greatly reduce the load of HVAC systems and save electric energy. In experiments, a PCM wallboard room was constructed by attaching PCM wallboards, developed by incorporating about 26% PCM by weight into gypsum wallboards, to the surface of an ordinary wall. The transition temperature and latent heat of these PCM wallboards were tested by differential scanning calorimetry (DSC). The room testing was conducted to determine the latent heat storage of PCM wallboards. Through experiments, it could be proved that DSC can effectively predict the performance of a full-scale installation of PCM wallboards. Compared with an ordinary room, it was found that the PCM wallboard room could greatly reduce the energy cost of HVAC systems and transfer electric power peak load to valley.     

Heat transfer and thermal storage behaviour of gypsum boards incorporating micro-encapsulated PCM

In the application of energy storage and thermal environmental control, PCM (Phase Change Material) is a very promising material choice. This study incorporated mPCM (micro-encapsulated PCM) into gypsum to make mPCM gypsum board and then investigated the physical properties, heat transfer and thermal storage behaviour. The major control parameters are wall temperatures and the weight percentages of mPCM added to the gypsum boards. A melting fraction correlation, reduced from our test data and based on Stefan number (Ste), subcooling (Sb) and Fourier number, is proposed. It shows that case with a higher Ste or Sb can have a higher heat transfer through the hot wall. Thermal storage behaviour of mPCM gypsum boards is then analyzed.     

聚羧酸减水剂与三种其他高效减水剂的复合效应研究

在不添加小分子缓凝剂的条件下研究了聚羧酸系高效减水剂与脂肪族系、三聚氰胺系、萘系等高效减水剂的复合效应,制得三种复合型减水剂。结合1d龄期硬化水泥浆体XRD、SEM、IR分析,研究了复合减水剂对水泥水化速率的影响,并通过水泥颗粒表面的（电位经时变化,探讨了复合减水剂的作用机理。此外,还测试了复合减水剂的水泥净浆性能及混凝土性能。     

Preparation and characterization of fatty acid ester/building material composites for thermal energy storage in buildings

In this study, fatty acid ester/building material composites as novel form-stable phase change materials (PCMs) were prepared by absorbing liquid fatty acid esters into porous network of conventional building materials. In the composite erythritol tetrapalmitate (ETP) and erythritol tetrastearate (ETS) esters were used as PCM for thermal energy storage, and cement and gypsum used as supporting material. The composite PCMs were characterized using scanning electron microscope (SEM) and Fourier transformation infrared (FT-IR) analysis technique. The SEM results showed that the esters were confined in the porous network of the cement and gypsum. Thermal properties and thermal stabilities of the composite PCMs were determined by using differential scanning calorimetry (DSC) and thermal gravimetric (TG) analysis techniques. DSC results showed that the melting temperatures and the latent heats of the prepared composite PCMs were in range of 21.6-32.3 °C and 35.9-43.3 J/g, respectively. TG analysis indicated that the composite PCMs had good thermal stability. The thermal cycling test including 1000 heating and cooling process was conducted to determine the thermal reliability of the composite PCMs and the test results revealed that the composite PCMs have good thermal reliability and chemical stability.     

脱硫石膏复合胶凝材料及其激发效果研究

采用脱硫石膏为主要原料,制备了脱硫石膏-水泥-粉煤灰复合胶凝材料,考察了激发剂对其改性效果及显微结构特征。结果显示掺52%脱硫石膏,31%水泥,12%粉煤灰,5%激发剂时,复合胶凝材料后期强度较高,其28d强度可达到64.6MPa。14～28d试样抗压强度呈急剧增加趋势,其原因可能是后期水泥水化和粉煤灰二次水化所致。在脱硫石膏-水泥体系中,存在较多物理键和少量化学键,而掺加Al2O24-离子激发水泥和粉煤灰可形成致密凝聚-结晶复合结构。