【作者】 元伟；

【导师】 李再峰；

【作者基本信息】 青岛科技大学 ， 应用化学， 2008， 硕士

【摘要】 提高聚氨酯的耐温性能是聚氨酯应用的重要研究内容。论文从三方面合成新型聚氨酯弹性体,即软段主链选择,有机蒙脱土纳米材料的复合和邻接交连网络增强。首先研究了端羟基丁腈液体橡胶(HTBN)作为软段材料对制备聚氨酯弹性体性能影响。随后分别用丁腈羟与聚四氢呋喃醚二醇、聚己內酯二醇、聚碳酸酯二醇共混制备聚氨酯弹性体材料,研究了其力学性能和热学性能,并研究了交联剂对聚氨酯弹性体材料性能的影响。结果表明:丁腈羟制备的聚氨酯弹性体的高温性能优异,最大热分解峰在450-460℃之间;丁腈羟与聚四氢呋喃二醇(PTHF)以8:2的质量比共混时,制得的聚氨酯弹性体的拉伸强度为25MPa,耐热性能也比较优越;用三羟甲基丙烷为交联剂制得交连网络结构的聚氨酯弹性体,力学性能和热性能都有所提高;双二五打开丁腈羟主链上的双键,进一步加强了聚氨酯的交连,使其聚氨酯弹性体的力学性能及耐热性能进一步增强。用纳米有机蒙脱土制备聚氨酯/蒙脱土纳米复合材料。通过示差扫描量热法(DSC)、热失重分析(TGA)等仪器表征了聚氨酯/有机蒙脱土纳米复合材料的耐热性能。结果表明:有机蒙脱土(OMMT)与不同混合体系的聚氨酯复合,所得到的材料的拉伸力学性能提高了约3~4MPa;热分析结果表明复合材料的Tg得到提高,热稳定性亦有一定程度的改善。研究高温下双马树脂(如N,N’-间苯撑双马来酰亚胺)的不饱和键与软段(丁腈橡胶)分子中的不饱和键之间的自由基聚合反应,合成出邻接网络结构型聚氨酯弹性体。研究邻接交联网络密度对丁腈基聚氨酯弹性体的高温力学性能及热稳定性的影响规律。结果表明:随着HVA-2的增多,聚氨酯弹性体试样在第一热分解峰温度有所升高,由原来的279℃左右开始分解升高到290.4℃,力学性能也有所增强。更多还原

【Abstract】 Recently, in order to enlarge polyurethane’s application fields, improving the thermal performances of polyurethane has been became one of the key point in the field. In this dissertation, it consists of three main parts about synthesis as follows: the choice of soft main chain, synthesis of organic montmorillonite nanocomposite and reinforcement of adjacent cross-linked network.The effect of the soft segment based on liquid hydroxyl terminated polybutadine-acrylonitrile copolymer glycol(HTBN) on the performance of PU were discussed, then polytetramethylene ether glycols(PTHF), poly-ε-caprolactone polyol, polycarbonatediols were separately blended with HTBN to synthesize polyurethane elastomers and the mechanical and thermal properties were studied. The effect of crosslinking agent was discussed. The results showed that the polyurethane based on HTBN possessed excellent thermal properties,the first thermal decomposition temperature was among 450℃-460℃; The HTBN and PTHF were blended by the weight ratio of 8/2 and prepared the polyurethane elastomers,which tensile strength was 25MPa and possessed good thermal property. The TMP cross-linked agent was introduced into the polyurethane and cross-linked network structure was obtained, the mechanical and thermal properties were improved;The double bond of HTBN reacted with B25 and the degree of cross-link was reinforced ,the properties were enhanced.The OMMT nanocomposite were used to prepare polyurethane nanocomposites. The thermal property of polyurethane nanocomposites were studied in details by DSC and TGA. It showed that the tensile strength of polyurethane which was prepared by the blends of OMMT and different polyols systems was enhance about 3~4MPa. The Tg of PU/OMMT nanocomposites increased with increasing the OMMT, and the thermal stability was improved.The free-radical polymerization between unsaturated bond in the bismaleimide (e.g. HVA-2) and unsaturated bond in the soft segment (NBR) was studied and prepared the adjacent crosslinked network polyurethane elastomers. The mechanical and thermal stability properties with degree of adjacent crosslinked network was investigated. It was found that the first thermal decomposition temperature was improved with the increasing of HVA-2,which was 290.4℃higher than 279℃before, and the mechanical property was improved.更多还原