CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2016年第35卷第4期·1144·
化工进展
聚氨酯预聚体增韧改性酚醛泡沫塑料
吴崇珍1，高书亚2，张丽2
（1河南教育学院化学系，河南郑州 450046；2郑州大学材料科学与工程学院，河南郑州 450052）摘要：采用异氰酸酯封端且不含游离异氰酸酯单体的聚氨酯预聚体作为酚醛泡沫的增韧改性剂，并在后期混合发泡工艺中减少酸性固化剂的用量，制备了不粉化、韧性高的改性酚醛泡沫体，并考察了异氰酸酯基含量对酚醛泡沫体的表观密度、压缩强度、吸水率、阻燃性和导热性能等的影响。结果表明：随着聚氨酯预聚体用量以及异氰酸酯基含量的增加，改性酚醛泡沫体的表观密度、压缩强度增大；当异氰酸酯基含量为8.6%时，抗粉化程度最好；随着聚氨酯预聚体用量的增加，吸水率和热导率变化不大，当聚氨酯用量不超过6%时，临界氧指数仍大于40。
关键词：酚醛泡沫；聚氨酯预聚体；抗粉化；导热性
中图分类号：TB 332 文献标志码：A 文章编号：1000–6613（2016）04–1144–05
DOI：10.16085/j.issn.1000-6613.2016.04.028
Phenolic foam modified with polyurethane prepolymer
WU Chongzhen1，GAO Shuya2，ZHANG Li2
（1Department of Chemistry，Henan Institute of Education，Zhengzhou 450046，Henan，China; 2 School of Material Science and Engineering，Zhengzhou University，Zhengzhou 450052，Henan，China）Abstract：The toughening phenolic foam with low pulverization was prepared by adding polyurethane prepolymer which is terminated with isocyanate and without free isocyanate monomer，and by reducing the consumption of acidic curing agent in the foaming process. The effect of isocyanate content on the apparent density，compressive strength，water intake，flame retardant and heat conductivity of phenolic foam were also discussed. The results showed that the apparent density and compressive strength of the modified phenolic foam tended to increase with the content of polyurethane prepolymer and corresponding isocyanate group. Meanwhile，the resistance to pulverization is the best when the isocyanate content is 8.6%. However，the water absorption and heat conductivity of the modified polyurethane foam changed little with the increase of polyurethane prepolymer. The critical oxygen index was still more than 40 when the content of polyurethane was less than 6%.
Key words：phenolic foam；polyurethane prepolymer；resistance to pulverization；heat conduction
酚醛泡沫塑料是一种物美价廉的轻质绝热材料，其耐热性能和防火性能大大优于聚氨酯与聚苯乙烯等泡沫塑料，特别适用于易发生火灾的化工、石油、建筑等领域的隔热保温材料。但是酚醛泡沫存在韧性差、脆性大、易于粉化掉渣的缺陷，限制了其广泛使用。为此，人们采取多种手段对酚醛泡沫改性以提高韧性，如采用硅烷偶联剂、腰果壳油、柔性环氧、钼、松香、三聚氰胺等改性酚醛泡沫[1-8]。其中采用聚氨酯改性酚醛泡沫可以提高制品的强度，降低密度及热导率，并能提高制品的韧性，被认为是最有成效的改性方法之一[9-13]。
一般认为，聚氨酯预聚体中的端异氰酸酯基可以和酚醛树脂中的羟甲基反应，在形成的泡沫网络收稿日期：2015-07-28 ；修改稿日期：2015-11-06。
第一作者：吴崇珍（1961—），女，教授，研究方向为精细化工、分
析技术。E-mail wcz617983@https://www.doczj.com/doc/dd16473446.html,。联系人：张丽，教授。E-mail lizhang9@https://www.doczj.com/doc/dd16473446.html,。