实验过程采用热压浸渍加入发泡剂方法制备发泡型SiO2气凝胶核/聚苯乙烯壳复合珠粒,当加入14份发泡剂珠粒在90℃、压力0.9 MPa条件下反应9 h制备得到发泡剂含量为7％左右的可发性复合珠粒。同时对其发泡成型的原理、工艺流程、影响因素及参数控制等进行了研究,实验结果表明,在蒸汽压力为0.4 MPa的条件下经40 s制备得到发泡倍率为20左右、密度为0.025 g/cm3的预发复合珠粒,再经过模塑蒸汽发泡,蒸汽压力0.35 MPa、通气时间180 s,最终制备出保温性能优异(导热系数可达0.026 W/( m·K))、力学性能良好的SiO2气凝胶核/聚苯乙烯壳复合保温板。%In the process of experiment, expandable SiO2 aerogel core/polystyrene shell beads were prepared by adding foaming agent and being impregnated in hot-pressing. Under the conditions of adding 14 phr foaming agent at 90 ℃ and reaction for 9 h at a pressure of 0. 9 MPa, the prepared expandable composite beads foaming agent content were about 7%. The process flow of foam molding was studied, including the influence factors and the parameters of control principle. The experimental results showed that the expandable beads’ density was 0. 025 g/cm3 and the foaming ratio reached 20. After the pre-foaming experiment, the pre-foaming beads can be used to prepare the insulation board at the conditions of 0. 35 MPa steam pressure and 180 s processing time in the foaming box. The final insulation boards’ thermal conductivity was down to 0. 026 W/( m · K ) and the boards had excellent mechanical properties too.
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