Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easi...Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easier operation, s horter reaction time and higher yield. The yields of seven derivatives of 1,3- dithiocyclohexane are between 58% and 75%. The optimum molar ratio of 1,3-d ichloropropane to sodium thiosulfate was 1∶1 in the preparati on of Bunte′s salt. The structures of seven derivatives were characterized by m eans of IR, 1H NMR, MS.展开更多
以1,5-萘二胺和对羟基苯甲酸为原料合成了一种新型含萘环结构的固化剂(GNA),并且用核磁共振氢谱(1 H NMR)确定了物质的结构。通过垂直燃烧法(UL 94V)、热重分析(TGA)、扫描电镜(SEM)、吸水性测试和力学性能测试对不同质量分数添加量的GN...以1,5-萘二胺和对羟基苯甲酸为原料合成了一种新型含萘环结构的固化剂(GNA),并且用核磁共振氢谱(1 H NMR)确定了物质的结构。通过垂直燃烧法(UL 94V)、热重分析(TGA)、扫描电镜(SEM)、吸水性测试和力学性能测试对不同质量分数添加量的GNA改性联苯型环氧树脂(YX-4000)的阻燃性能、热性能、吸水性和力学性能进行了研究。实验结果表明,随着固化剂GNA含量的增加,固化物的阻燃性能得到了提升,在GNA含量达到15%(质量分数)时,阻燃级别可以达到UL-94V-0级。为了深入研究其阻燃机理,通过TGA和SEM对其燃烧残渣分析发现,固化物的表面有致密的炭层起到隔绝空气的作用,阻止燃烧进一步发生,在20%(质量分数)含量时,800℃的残炭率高达50%。另外通过吸水性和力学性能测试研究发现,与传统阻燃剂相比,固化物阻燃性提高,力学性能和吸水性能下降较小。在15%(质量分数)添加量时拉伸强度和拉伸模量为101 MPa和76GPa,弯曲强度和弯曲模量为29 MPa和26GPa,吸水率为1.626。展开更多
文摘Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easier operation, s horter reaction time and higher yield. The yields of seven derivatives of 1,3- dithiocyclohexane are between 58% and 75%. The optimum molar ratio of 1,3-d ichloropropane to sodium thiosulfate was 1∶1 in the preparati on of Bunte′s salt. The structures of seven derivatives were characterized by m eans of IR, 1H NMR, MS.
