通過化學發泡法研究過氧化氫(H2O2)作為發泡劑，十二烷基硫酸鈉(SDS) 作為發泡穩定劑，碘化鉀(KI)作為發泡劑的催化劑以及矽酸鈉模數對發泡無機聚合物工程性能的影響。進行數次試驗求得其掃描電子顯微鏡、乾密度、熱傳導係數、抗壓強度、吸水率和吸水性、孔隙率、孔徑分佈和微觀結構分析等目標性能。通過ImageJ圖像分析儀獲得孔徑分佈。還分析了泡沫無機聚合物的孔隙特徵與工程性能之間的相關性。泡沫無機聚合物的乾密度，抗壓強度和熱傳導係數隨著過氧化氫的增加而降低，並導致較大孔體積的快速發展，因此總孔隙率和吸水效果更高。十二烷基硫酸鈉有助於產生更多的氣泡，並具有均勻的層次。碘化鉀可以用作於1.5％過氧化氫的催化劑。將所得數據分析後，通過在SEM圖像中觀察到之大孔隙。工程性質與泡沫無機聚合物的孔結構參數具有良好的相關性。當使用十二烷基硫酸鈉（SDS）作為穩定劑時，過氧化氫的最佳用量為2％和1.5％。研究表明，使用3.0的矽酸鈉模數可以得到良好的孔隙結構。與使用SDS作為穩定劑的泡沫無機聚合物相比，含過氧化氫的泡沫無機聚合物的孔隙尺寸分佈具有更多小孔，後者通過使用SDS獲得更大的孔隙獲得較緻密的結構。無機聚合物基質中的開孔可以產生更高的孔隙率，更低的密度和強度，以及更低的熱傳導係數因此可以作為隔熱材料。從微觀結構和形態特徵可以用來解釋其大孔結構，支持所得數據並且了解其泡沫無機聚合物之工程性質。

關鍵詞：過氧化氫，十二烷基硫酸鈉，碘化鉀，矽酸鈉模數，泡沫無機聚合物，孔隙率，孔徑分佈，隔熱材料

The effects of hydrogen peroxide as a foaming agent, sodium dodecyl sulfate as foaming stabilizer, potassium iodide as the catalyst of foaming agent and sodium silicate modulus on the engineering properties of foamed geopolymer through chemical foaming method have been investigated. Several tests had been performed to obtain the target properties such as dry density, thermal conductivity, compressive strength, water absorption and sorptivity, porosity, pore size distribution and microstructural analysis through scanning electron microscopy. Pore size distributions were obtained by ImageJ image analyzer. The correlation between the pore characteristics and the engineering properties of foamed geopolymer was also analyzed. Dry density, compressive strength and thermal conductivity of foamed geopolymer were decreased with the increase of hydrogen peroxide and resulted in the fast development of larger pore volume, and consequently higher amounts of the total of porosity and absorption level. Sodium dodecyl sulfate help generates more bubbles with uniform gradation. Potassium iodide can be used to perform as a catalyst which is equivalent to 1.5% of hydrogen peroxide. The resulting data had been confirmed by the observation of macropores in the SEM images. The engineering properties have a good correlation with pore structure parameters of foamed geopolymer. The optimum amount of hydrogen peroxide was 2% and 1.5% while using sodium dodecyl sulfate (SDS) as a stabilizer. The research showed that a good pore structure could be obtained when using sodium silicate modulus of 3.0. The pore size distribution of foamed geopolymer containing hydrogen peroxide has a higher amount of smaller pores than those of foamed geopolymer using SDS as a stabilizer that attained the denser structure by using SDS to obtain larger open pores. The open pores in the geopolymer matrix can produce higher porosity, lower density and strength, also the lower thermal conductivity to be as the insulation materials. The microstructure and morphology characteristics could be explained by the macropores structure and became the supporting data to understand the result of engineering properties of foamed geopolymer.

Keywords: hydrogen peroxide, sodium dodecyl sulfate, potassium iodide, sodium silicate modulus, foamed geopolymer, porosity, pore size distribution, insulation material, engineering properties

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