Effect of Chemical Structure and Apparent Density of Rigid

The aim of this work was to synthesize polyurethane foams based on petrochemical polyols and biopolyols with specific apparent densities (40, 60, 80, 100, and 120 kg/m3), test their properties, glycolyze them, and finally analyze each glycolyzed product. The petroleum-based foams, used as reference foams, and the bio-based foams underwent a series of standard tests to define their properties (the content of closed cells 20–95%, compressive strength 73–1323 kPa, thermal conductivity 24–42 mW/m∙K, brittleness 4.6–82.9%, changes in linear dimensions < 1%, and water absorption < 1%). Taking into account the need for recycling, the foams were shredded and then glycolyzed by diethylene glycol, with the addition of a catalyst in the form of potassium hydroxide. The chemolysis products were analyzed through determination, i.e., the amine and the hydroxyl values, viscosity, and molecular weight. The obtained rebiopolyols had hydroxyl numbers ranging from 476 to 511 mg KOH/g. The type of biopolyol used in the PUR foam systems had a significant impact on the amine number and the viscosity of the obtained rebiopolyol.本研究旨在以石化基多元醇与生物基多元醇为原料，合成表观密度分别为40、60、80、100及120 kg/m³的聚氨酯泡沫，随后对其性能进行测试，再将泡沫进行乙二醇解聚处理，并最终对每一份解聚产物开展分析。本研究以石油基泡沫作为对照试样，与生物基泡沫一同开展一系列标准性能测试，测试指标包括闭孔率20%~95%、抗压强度73~1323 kPa、导热系数24~42 mW/(m·K)、脆性4.6%~82.9%、线性尺寸变化率<1%以及吸水率<1%。考虑到材料回收的需求，研究人员先将泡沫粉碎，再以二甘醇作为解聚溶剂，添加氢氧化钾作为催化剂进行乙二醇解聚。通过胺值、羟值、粘度及分子量测定等手段，对化学解聚产物进行分析表征。所制备的再生生物基多元醇（rebiopolyols）的羟值范围为476~511 mg KOH/g。聚氨酯（PUR）泡沫体系中所使用的生物基多元醇类型，对所制备的再生生物基多元醇的胺值与粘度具有显著影响。