碳酸丙烯酯改性2-甲基咪唑固化剂的制备与应用

Preparation and Application of 2-Methylimidazole Curing Agent Modified by Propylene Carbonate

利用碳酸丙烯酯(PC)与2-甲基咪唑(2-MI)进行羟烷基化取代反应,合成了碳酸丙烯酯改性2-甲基咪唑(PC-MI)固化剂。将所合成的PC-MI固化剂与E-44环氧树脂配制成胶黏剂,通过胶料的硬化时间、凝胶时间、拉伸性能测试,考察了改性固化剂的合成工艺和使用工艺条件对PC-MI胶黏剂性能的影响。结果表明,PC-MI固化剂的优化合成工艺条件为,PC与2-MI按摩尔比2:1在135℃反应4 h,其合适用量为E-44环氧树脂质量的12%;由此得到的环氧胶料室温凝胶时间为96 h,在140℃固化3 h后,拉伸剪切强度、断裂伸长率分别达到31.58 MPa,5.08%。相较于2-MI,PCMI固化剂与环氧树脂更易混溶,所配胶料室温凝胶时间得到有效延长,拉伸剪切性能优良。

Propylene carbonate modified 2-methylimidazole(PC-MI)curing agent was synthesized by hydrox-yl alkylation of propylene carbonate(PC)with 2-methylimidazole(2-MI).The synthesized PC-MI curing agent and E-44 epoxy resin were formulated into adhesives,and the effects of synthetic process and curing conditions of the curing agent on the properties of the prepared adhesives were investigated by the test of setting time,gel time and tensile shear performance.The results show that the optimized PC-MI curing agent can be obtained by the re-action of PC and 2-MI at 135℃for 4 h with the mole ratio of 2:1;The optimal dosage of PC-MI accounts for 12%of E-44 epoxy resin,and the resulting adhesive has a room temperature gel time of 96 h.After curing for 3 h at 140℃,the tensile shear strength and elongation at break of the adhesive can reach at 31.58 MPa and 5.08%re-spectively.Compared with 2-MI,PC-MI curing agent can easily mix with epoxy resin,get longer gel time at room temperature,excellent tensile and shear properties.