蓖麻油基聚醚型聚氨酯弹性体的制备与工艺研究

Research on castor oil-based polyether-polyurethane elastomer

以蓖麻油基聚氧乙烯醚(EL)和聚四氢呋喃醚二醇(PTMG)为软段,1,6-六亚甲基二氨基甲酸甲酯(HDC)为硬段,二月桂酸二丁基锡(DBTDL)为催化剂,1,4-丁二醇(1,4-BDO)为扩链剂,采用酯交换缩聚法制备蓖麻油基聚醚型聚氨酯弹性体(CEUs)。利用红外光谱、热重分析、拉伸性能测试等对CEUs进行分析与表征。通过单因素对比实验探讨了物料配比、预聚阶段的温度、时间和压力及缩聚阶段的温度和时间等对蓖麻油基聚醚型聚氨酯弹性体力学性能的影响。结果表明,较优的制备工艺条件为:n(EL)∶n(PTMG)=1∶5、n(软段)∶n(硬段)=1∶1. 07、预聚温度为110℃、预聚时间为45 min、预聚压力为0. 03 MPa、缩聚温度为170℃、缩聚时间为180 min。在该制备工艺条件下,伸长率达到972. 38%,断裂拉伸强度为3. 23 MPa,邵尔A硬度为60。

Copolymerized polyether-polyurethane elastomers( CEUs) are prepared by transesterification polycondensation method with castor oil-based polyoxyethylene ether( EL),polyoxytetramethylene glycol( PTMG) and1,6-dimethylhexane dicarbamate( HDC) as raw materials,dibutyltin dilaurate as catalyst,and 1,4-butanediol as chain extender.EL and PTMG are used as the soft segment,and HDC is used as the hard segment.The properties of CEUs are characterized by IR,TGA and mechanical performance tests. Effects of the material ratio,the temperature,time and pressure in pre-polymerization stage,and the temperature and time in polycondensation stage on the mechanical properties of CEUs are investigated by a series of single factor experiments.The results show that the optimum conditions are determined as follows: n( EL) ∶n( PTMG) = 1 ∶5,n( soft segment) ∶n( hard segment) = 1 ∶1. 07,the temperature,time and pressure are 110℃,45 min and 0. 03 MPa in the pre-polymerization stage,and the temperature and time 170℃ and180 min in the polycondensation stage. The CEUs prepared under the optimum conditions has a tensile strength of3. 23 MPa,an elongation at break of 972. 38%,and a Shore A hardness of 60.