本文關(guān)鍵詞：高性能氣凝膠保溫隔熱材料的常壓制備與性能研究　出處：《廣州大學》2014年碩士論文　論文類型：學位論文

  更多相關(guān)文章： SiO2氣凝膠 復合材料 保溫隔熱材料

【摘要】：SiO2氣凝膠是一種具有超低熱導率、超低密度、高孔隙率和高比表面積等特點的輕質(zhì)納米固態(tài)材料，但其本身的強度低、脆性大及生產(chǎn)成本高等原因限制了SiO2氣凝膠在建筑保溫隔熱領(lǐng)域上的應用。而常用保溫隔熱材料或是高導熱系數(shù)、吸濕性強或是耐燃性能差的原因限制了其在當今建筑保溫隔熱領(lǐng)域上的廣泛使用。針對SiO2氣凝膠和常用保溫隔熱材料的特點，本文采用正硅酸乙酯為硅源，以玻璃棉氈、玻璃針刺氈為增強相，通過溶膠－凝膠整體成型及常壓干燥工藝制備出一系列的玻璃纖維/SiO2氣凝膠復合材料。在常壓干燥工藝中，通過對復合凝膠兩步法和一步法制備工藝研究，確定了對復合凝膠的一步溶劑交換－表面改性處理工藝，并采用掃描電鏡、熱常數(shù)分析儀、熱重分析儀、光學接觸角測量儀和電子萬能試驗機等分別對玻璃纖維/氣凝膠復合材料的微觀結(jié)構(gòu)、導熱系數(shù)、熱穩(wěn)定性、疏水性能及力學性能進行了測試。 結(jié)果表明通過把SiO2氣凝膠與玻璃纖維氈復合，制得的復合材料具有低導熱系數(shù)、高疏水性、較高的力學性能及耐溫性能等特點。同時，多步溶劑交換－表面改性法與一步溶劑交換－表面改性法兩種處理方法所得的復合材料的各項性能較為接近：采用多步溶劑交換－表面改性法所得的玻璃棉氈/SiO2氣凝膠復合材料的導熱數(shù)系數(shù)為0.024W m-1K-1，靜態(tài)接觸角為124o，，抗拉、抗壓和抗彎強度由復合前的0.002、0.011和0.011MPa提高到0.213、1.474和0.252MPa。而對于玻璃針刺氈/SiO2氣凝膠復合材料，其導熱系數(shù)僅為0.025W m-1K-1，接觸角為112o，抗拉、抗壓和抗彎強度則均在1MPa以上。 改性液的配比為EtOH: TMCS:正已烷＝2:2:26時與原配比EtOH: TMCS:正已烷＝1:3:26所得復合材料的導熱系數(shù)均為0.022W m-1K-1，力學性能也很接近；對于不同氣凝膠添加量對復合材料性能的影響，當玻璃棉與玻璃棉氈/SiO2氣凝膠的質(zhì)量比為13%時，具有較好的綜合性能及經(jīng)濟性，此時復合材料的導熱系數(shù)為0.023W m-1K-1、接觸角為127°，抗拉、抗壓和抗彎強度分別為0.132、1.563和0.282MPa；另外，配比中無水乙醇量的增加對復合材料的導熱系數(shù)沒有影響，而隨著配比中無水乙醇的量的增加，復合材料的密度和力學性能逐漸降低，當無水乙醇量為原配比的2倍時，其密度低至148kg/m3。
[Abstract]:SiO2 aerogel is a kind of ultra low thermal conductivity, low density, lightweight nano solid materials with high porosity and high surface area characteristics, but its low strength, brittleness and high production cost reasons limit the SiO2 aerogel in application of thermal insulation in the field of building insulation and thermal insulation materials or used. High thermal conductivity, strong moisture absorption or burning resistance causes poor performance limits its wide use in the field of heat insulation. In today's architecture for SiO2 aerogel and used thermal insulation materials, using TEOS as silicon source, the glass wool felt glass mat reinforced by. Sol gel forming and whole atmospheric drying preparation process of glass fiber /SiO2 aerogel composite material. In a series of ambient pressure drying process, through the study on Preparation of composite gel two step method and one step method, are determined. The one step solvent composite gel exchange surface modification process, and using scanning electron microscopy, thermal constant analyzer, thermogravimetric analyzer, optical contact angle measuring instrument and electronic universal testing machine of glass fiber / aerogel composite material microstructure, thermal conductivity, thermal stability, and mechanical properties of hydrophobic the test.
The results show that the SiO2 aerogel and glass fiber composite, the composite materials with low thermal conductivity, high hydrophobicity, mechanical properties and heat resistance characteristics such as high. At the same time, the performance of multi - step solvent exchange surface modification method and one-step solvent exchange surface modification method of the two processing method of composite materials is close to: a multi step solvent exchange surface modification method of glass wool felt /SiO2 aerogel composite material thermal conductivity coefficient is 0.024W m-1K-1, static contact angle is 124o, tensile, compressive and flexural strength of the composite before 0.002,0.011 and 0.011MPa increased to 0.213,1.474 and 0.252MPa. for the glass mat /SiO2 aerogel composite material, its thermal conductivity is only 0.025W m-1K-1, the contact angle is 112O, tensile, compressive and bending strength is above 1MPa.
Modified liquid ratio of thermal conductivity of 1:3:26 composites produced are 0.022W = m-1K-1 EtOH: TMCS: = 2:2:26 and n-hexane than original EtOH: TMCS: n-hexane, the mechanical properties are also very close; for different aerogels addition effect on the properties of the composite materials, when glass wool and glass wool felt /SiO2 aerogel quality when the ratio is 13%, with comprehensive performance and good economy, the thermal conductivity of the composite was 0.023W m-1K-1, the contact angle is 127 DEG, tensile, compressive and flexural strength were 0.132,1.563 and 0.282MPa; in addition, absolute ethyl alcohol ratio increase in the thermal conductivity of composite materials has no effect, and with the the increase in the volume ratio of ethanol, the density and the mechanical properties of the composites decreased gradually, while 2 times amount of ethanol as raw ratio, the low density of 148kg/m3.

【學位授予單位】：廣州大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TU551

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本文編號：1427576