论文总字数：23737字

摘 要

高能耗已成为恶化我国生态环境、制约我国经济发展的重大瓶颈。真空绝热板（VIP）是目前最高效的超级隔热材料，主要包括芯材、膜材和气体吸附剂，具有导热系数低、质轻、超薄等优点，被广泛应用于航空航天、电池、冷藏冷链装备和建筑节能降耗领域。

VIP固体热传导率主要取决于芯材性能的优良，芯材一般选用低导热的多孔结构材料，利用内部孔隙限制残余气体的运动空间，减少气体对流传热。本文以纳米SiO₂颗粒和三种不同直径的玻璃棉纤维棉为原料，采用湿法成型工艺等步骤制备纳米颗粒增强玻璃纤维棉复合材料。采用光学显微镜观测玻璃棉纤维直径和直径分布；采用扫描电子显微镜（SEM）观察纳米颗粒增强玻璃纤维复合材料微观结构；分别采用热流法导热系数测试仪测试复合材料的导热系数和阻抗管测试不同规格的玻璃纤维和复合材料在不同频率下的隔声量，分析纳米颗粒对不同直径的玻璃纤维棉导热系数和隔声性能的影响规律。研究结果表明：

（1）对于纯玻璃棉和纳米SiO₂颗粒增强玻璃棉复合材料，导热系数随着纤维直径的降低（2.5μm→400nm）而减小，平均直径2.5μm的玻璃棉导热系数为0.0376W/(m•K)，平均直径400nm的玻璃棉导热系数可以达到0.029W/(m•K)；相同直径条件下，纳米SiO₂颗粒增强玻璃纤维棉复合材料的导热系数更低，纳米颗粒增强平均直径为2.5μm的玻璃纤维棉复合材料导热系数为0.037W/(m•K)，纳米颗粒增强平均直径为400nm的玻璃纤维棉复合材料导热系数可以达到0.027W/(m•K)。

（2）对于纯玻璃棉和纳米SiO₂颗粒增强玻璃棉复合材料，隔声性能随着纤维直径的减小（2.5μm→400nm）而增强，隔声量分贝逐渐增大。随着频率增加，从500Hz增加到6300Hz，平均直径400nm的玻璃棉隔声量从3.07分贝增至10.435分贝，相同直径条件下，纳米SiO₂颗粒增强玻璃纤维棉复合材料的隔声性能更好，纳米颗粒增强平均直径为400nm的玻璃纤维棉复合材料隔声量由6.425分贝增至14.63分贝。

（3）纤维直径越小，玻璃纤维棉内部孔隙也越小。孔隙尺寸的降低有利于降低材料的导热系数，复合材料的实质是添加纳米颗粒以减小孔隙尺寸，从而增强保温效果。

关键词：真空绝热板 芯材 复合材料 导热系数

Preparation and Performance Analysis of Nanoparticles Reinforced Glass Fiber Cotton Composites

ABSTRACT

High energy consumption has become a major bottleneck that worsens China’s ecological environment and restricts China’s economic development. Vacuum insulation panel (VIP) is currently the most efficient super insulation material, mainly including core material, membrane material and gas adsorbent. It has the advantages of low thermal conductivity, light weight, ultra-thin, etc. It is widely used in aerospace, batteries, refrigerated cold chain equipment and building energy-saving areas.

The VIP solid thermal conductivity mainly depends on the excellent performance of the core material. The core material is generally made of a porous material with low thermal conductivity. The internal pores are used to limit the movement space of the residual gas and reduce the convective heat transfer of the gas. In this paper, nano-SiO₂ particles and three kinds of glass wool fibers of different diameters were used as raw materials. Nano-grain reinforced glass fiber/cotton composites were prepared by wet forming process. The optical fiber microscope was used to observe the diameter and diameter distribution of the glass wool fibers. The scanning electron microscope (SEM) was used to observe the microstructure of the nano-particle reinforced glass fiber composites. The heat conductivity coefficient tester was used to test the thermal conductivity of the composite materials and the impedance tube test different specifications. The sound insulation of glass fibers and composites at different frequencies was used to analyze the influence of nanoparticles on the thermal conductivity and sound insulation performance of glass fiber cotton with different diameters. Research indicates:

(1) For pure glass wool and nano-SiO₂ particle-reinforced glass wool composites, the thermal conductivity decreases with decreasing fiber diameter (2.5 μm → 400 nm), and the thermal conductivity of glass wool with an average diameter of 2.5 μm is 0.0376 W/(m • K), the average thermal conductivity of glass wool with a diameter of 400 nm can reach 0.029 W/(m•K); under the same diameter, the thermal conductivity of nano-SiO₂ particles reinforced glass fiber/cotton composites is lower, and the average diameter of nanoparticles is 2.5 The thermal conductivity of μm glass fiber cotton composites is 0.037W/(m•K), and the thermal conductivity of glass fiber cotton composites with nanoparticle reinforced mean diameter of 400nm can reach 0.027W/(m•K).

(2) For pure glass wool and nano-SiO₂ particle-reinforced glass wool composites, the sound insulation performance increases as the fiber diameter decreases (2.5 μm → 400 nm), and the sound insulation decibels gradually increase. With the increase of frequency, from 500 Hz to 6300 Hz, the sound insulation of glass wool with an average diameter of 400 nm increased from 3.07 dB to 10.435 dB. Under the same diameter, nano-SiO₂ particles enhanced the sound insulation performance of glass fiber cotton composites better. The sound insulation of the glass fiber cotton composite with an average diameter of 400 nm was increased from 6.425 dB to 14.63 dB.

(3) The smaller the fiber diameter, the smaller the internal pores of the glass fiber cotton. The reduction of pore size is beneficial to reduce the thermal conductivity of the material. The essence of the composite material is to add nanoparticles to reduce the pore size, thereby enhancing the heat preservation effect.

Key words: Vacuum insulation board; Core; Composite materials; Thermal Conductivity

目 录

摘 要 Ⅰ

ABSTRACT Ⅱ

第一章绪论 1

1.1背景与意义 1

1.2芯材的研究现状 2

1.3芯材的特性 3

1.4芯材的分类 5

1.5选题依据和研究内容 6

第二章 材料制备及性能表征 8

2.1 实验材料和仪器 8

2.2 测试表征 11

第三章 实验结果与讨论 13

3.1 不同直径的玻璃纤维和SiO₂纳米颗粒表征 13

3.2 纳米颗粒增强玻璃纤维复合材料导热系数 16

3.3纳米颗粒增强玻璃纤维复合材料隔声性能 17

3.4纳米颗粒增强玻璃纤维复合材料微观结构 19

第四章 结论与展望 25

4.1 结论 25

4.2 展望 26

第五章 经济分析 27

参考文献 29

致谢 31

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