凝固剂和稳定剂对无氨天然胶乳成型胶膜下滑的影响

Effect of Coagulant and Stabilizer on Sliding of Ammonia Free Natural Rubber Latex Film during Molding

针对无氨天然胶乳胶膜成型时从模具上下滑(简称下滑)的问题,以气球为例研究凝固剂和稳定剂对无氨天然胶乳成膜性能的影响。结果表明:凝固剂中的二价钙盐和附型剂种类及用量并非无氨天然胶乳胶膜下滑的主要影响因素;壁厚较大的胶膜成型过程中,配合胶乳中的氨和氢氧化钾对浸渍在模具上的凝固剂具有膨胀和增稠的作用,有利于阻止成型胶膜下滑,其中氨的作用更为突出;稳定剂中不加氨和氢氧化钾的无氨天然胶乳在成型过程中缺少能使凝固剂在自然条件下产生膨胀和增稠的作用,胶膜与模具的附着力不能随胶乳成型进程而增大,胶膜与模具的附着力小是造成无氨天然胶乳胶膜下滑的主要原因。

In order to solve the problem of the film sliding of ammonia free natural rubber latex from mould during molding(shorted for the film sliding),the effect of the coagulant and stabilizer on the filmmolding performance of ammonia free natural rubber latex was studied by taking balloon as an example.The results showed that,the type and amount of divalent calcium salt and co-forming agent in the coagulant were not the main factors influencing the film sliding.During the molding process of the film with a large wall thickness,ammonia and potassium hydroxide in the compounding latex had the effect of expanding and thickening the coagulant impregnated on the mould,which was beneficial to prevent molding film sliding,and the role of ammonia was more outstanding.In the molding process,ammonia free natural rubber latex lacked the effect of expanding and thickening under natural conditions since there was no ammonia and potassium hydroxide in the stabilizer,and the adhesion between the film and mould could not get increased with the proceeding of latex molding.The main reason for the film sliding was the low adhesion between the film and mould.