论文总字数：34019字

摘 要

太阳能因具有“无限性”、普遍性、经济性和清洁性等特点，必将成为全球理想的替代能源。同时太阳能也存在间歇性、不可预测性以及分散性等缺点，使其在应用时受到了限制。以蓄热材料作为储能介质的蓄热技术很好地解决了这个问题。蓄热材料的耐久性是指蓄热材料在多次储热和放热循环后保持蓄热性能的能力，其在很大程度上决定了以蓄热材料作为蓄热介质的蓄热系统的经济性和可行性。

以季戊四醇为研究对象，进行不同次数的热循环试验，同时采用熔融共混法法制备季戊四醇/新戊二醇二元固固相变材料。通过差示扫描量热法(DSC)以及傅里叶红外光谱(FT-IR)等测试手段测定不同次数热循环后蓄热材料的结构和性能，研究其耐久性。

季戊四醇的相变温度为188.2℃，相变潜热为224.3J/g；未密封状态下，100次热循环后，其质量降低了26.5%；密封状态下，12次热循环试验后，季戊四醇起始温度和相变焓分别降低了10.4%和14.4%，在热循环过程中有新物质生成，季戊四醇在应用中不能保持良好的热稳定性。

PE含量为20%、40%、60%和80%时PE/NPG二元相变材料的相变温度分别为34.2℃、34.7℃、33.3℃和31.8℃，相变潜热分别为61.3、21.3、17.1和11.1J/g。随着季戊四醇含量的升高，PE/NPG的相变潜热显著降低，所以在应用中应选择PE的含量为20%时的PE/NPG二元相变材料。未密封状态下，100次热循环后样品的质量约降低了30% ，所以样品在应用中应封装。密封状态下，0、100次热循环后得到的样品的相变温度分别为35.1℃和33.9℃，相变焓分别为57.2J/g和63.5J/g，其相变温度和相变潜热的变化率均在±3%以内，说明该样品在100次热循环过程中仍具有良好的热稳定性，能够在室温下使用。

关键词：耐久性；新戊二醇；季戊四醇；热物性；DSC

ABSTRACT

Solar energy will become the global ideal alternative energy for its characteristics of infinity, universality, affordability and cleanliness. But the application of solar energy is restricted for its shortcomings such as intermittence, unpredictability and dispersion. The thermal energy storage technique which uses the heat storage material as the heat storage medium is a good solution to the problem. The durability of the heat storage material refers to the ability of keeping the storage performance suffering a number of thermal cycles, and that determines the feasibility and efficiency of the heat storage system to a large extent.

Pentaerythritol was selected as the research object and a number of thermal cycles were conducted and melt blending method was used to PE/NPG phase change material. Then the properties, structure and durability of the materials were studied by differential scanning calorimetry (DSC), Fourier transform infrared spectrometer (FT-IR) and other test methods.

The phase change temperature and latent heat of pentaerythritol were 188.2℃ and 224.3J/g. The decrease in the mass of pentaerythritol with unsealed condition was 26.5% after 100 cycles. The decrease in melting temperature and latent heat of pentaerythritol with unsealed condition was 10.4% and 14.4% respectively and accompanied with new substances after 12 cycles. It is indicated that pentaerythritol can not keep thermal stability in the application.

The phase change temperature and latent heat of PE/NPG were 34.2℃, 34.7℃, 33.3℃, 31.8℃ and 61.3, 21.3, 17.1, 11.1J/g respectively when the mass fraction of pentaerythritol were 20%, 40%, 60% and 80%. The latent heat of PE/NPG decrease as the mass fraction of pentaerythritol increased. The 20%-PE/80%-NPG phase change material was selected for the application. The decrease in the mass of NPG/PE with unsealed condition was 30% after 100 cycles. The change in phase change temperature and latent heat with unsealed condition was very small. It is indicated that NPG/PE can keep thermal stability in the application.

KEYWORDS: durability; neopentyl glycol; pentaerythritol; thermophysical properties; differential scanning calorimetry

目 录

摘 要 I

ABSTRACT II

第一章 绪论 1

1.1 引言 1

1.2 太阳能储热材料 1

1.2.1 显热储热材料 2

1.2.2 潜热储热材料 2

1.3 太阳能蓄热材料的研究进展 5

1.3.1 显热蓄热材料的研究现状 5

1.3.2 相变材料的研究进展 6

1.4 课题主要研究内容 10

第二章 季戊四醇的蓄热性能及耐久性研究 11

2.1 原材料及实验过程 11

2.1.1 原材料 11

2.1.2 加速热循环实验 11

2.1.3 测试方法 12

2.2 季戊四醇简介 12

2.3 季戊四醇封装条件的确定 13

2.4 季戊四醇的外观 15

2.5 季戊四醇的相变温度和相变潜热 16

2.6 季戊四醇的成分 19

2.7 结论 20

第三章 季戊四醇/新戊二醇二元相变材料蓄热性能的研究 21

3.1 原材料及试验过程 21

3.1.1 原材料 21

3.1.2 PE/NPG复合相变材料的制备方法 21

3.1.3 测试方法 22

3.2 NPG/PE二元固-固相变材料的热物性研究 22

3.3 PE/NPG二元相变材料的耐久性研究 23

3.3.1 热循环条件的确立 23

3.3.2 封装条件的确立 23

3.3.3 相变潜热和相变温度的变化 24

3.4 结论 25

第四章 结论及展望 27

4.1 结论 27

4.2 展望 27

参考文献 29

致 谢 35

第一章 绪论

1.1 引言

能源是人类赖以活动的物质基础，是人类得以生存的关键因素。随着国民经济的快速发展，能源在人们工作和生活中所扮演的角色越来越重要，致使能源的消耗加剧，同时能源的紧缺和能源活动所带来的环境污染问题又严重制约了我国经济的可持续发展^[1]。我国虽然是一个能源大国，但能源的问题一直是制约我国经济发展的主要因素，主要表现在下面几个方面：

请支付后下载全文，论文总字数：34019字