论文部分内容阅读
通过浇注成型的方法研究并发现了苎麻纤维与阴离子聚合尼龙6(APA-6)反应加工过程中严重的阻聚和变色问题.为了分析阻聚和变色的机理并寻找解决方案,选取了3种不同的引发剂(氢氧化钠、己内酰胺钠盐和己内酰胺溴化镁)分别与微晶纤维素(MCC)在150℃的真空条件下反应.然后分别采用傅里叶变换红外光谱、原子吸收光谱、X-射线衍射和核磁共振波谱表征了引发剂和MCC反应前后的变化.结果证明,阻聚和变色的机理是在强碱性和高温条件下,纤维素发生了剥皮反应,产生的副产物又极易与引发剂反应,因此导致APA-6中起引发作用的己内酰胺阴离子被消耗,从而使得聚合反应终止.另外,由于己内酰胺溴化镁(C1)的低活性和弱碱性,使得剥皮反应很大程度的降低,进而避免了引发剂阴离子的消耗,从而使得阻聚和变色问题得到明显改善,最终实现了通过反应加工的方法制备APA-6与苎麻纤维复合材料的目的.
In order to analyze the mechanism of polymerization inhibition and discoloration and to find a solution, three kinds of methods were selected and studied by pouring molding method and found that the reaction of ramie fiber and anionic polymerization nylon 6 (APA-6) Different initiators (sodium hydroxide, caprolactam sodium salt and caprolactam magnesium bromide) were respectively reacted with microcrystalline cellulose (MCC) under vacuum at 150 ℃ .Four Fourier transform infrared spectroscopy, atomic absorption spectrometry, X-ray diffraction and nuclear magnetic resonance spectroscopy were used to characterize the changes before and after the initiator and MCC reaction.The results show that the mechanism of polymerization inhibition and discoloration is the peeling reaction of cellulose under strong alkaline and high temperature conditions, Can easily react with the initiator, leading to the consumption of caprolactam anion, which initiates the priming effect in APA-6, so that the polymerization reaction is terminated.In addition, due to the low activity and weakly basicity of caprolactam bromide (C1), the debarking reaction To a large extent reduce the consumption of the initiator anions thereby avoiding the problem of aggregation and discoloration, and finally, the APA- 6 and ramie fiber composite material purposes.