工艺条件对生物基/EVA发泡鞋材中甲酰胺含量的影响研究

Effect of Technological Conditions on Formamide Content in Bio-Based/EVA Foamed Shoe Material

本文采用不同硫化温度、硫化时间、发泡剂用量制备了生物基/乙酸-醋酸乙烯酯(EVA)发泡鞋材,研究了上述工艺条件及贮存条件对发泡鞋材中甲酰胺含量的影响。研究结果表明,生物基/EVA发泡鞋材中的甲酰胺含量较高,结果受工艺条件影响较大。生物质复合鞋材的硫化温度严重影响甲酰胺含量,随着硫化温度的提高,甲酰胺含量会明显减少;在发泡剂用量和硫化温度相同的条件下,延长硫化时间,甲酰胺含量呈现明显的降低趋势;在硫化温度稍低的情况下,甲酰胺残留量与所用的发泡剂量呈正相关关系,发泡剂用量越大,甲酰胺的残留量越多;在不同贮存条件(贮存温度和时间)下对发泡片材的处理,会对甲酰胺残留量产生明显影响,随着放置时间的延长,其含量呈现明显下降趋势;超临界发泡工艺可以明显降低生物基/EVA产品中甲酰胺的含量,相关EVA发泡鞋材中都有少量甲酰胺的存在,但不会引起产品中甲酰胺含量超过规定限值。

This article prepared bio-based/EVA foam shoe materials using different vulcanization temperatures,vulcanization times,and foaming agent dosage.The effects of the above process and storage conditions on the for-mamide content in the foam shoe materials were studied.The research results indicate that the formamide content in bio-based/EVA foam shoe materials is relatively high,and the results are greatly affected by the process conditions.The vulcanization temperature of biomass composite shoe materials seriously affects the formamide content,and as the vulcanization temperature increases,the formamide content will significantly decrease.Under the same conditions of foaming agent dosage and curing temperature,prolonging the curing time results in a significant decrease in formamide content.At slightly lower vulcanization temperatures,there is a positive correlation between the residual amount of formamide and the foaming dosage used.The larger the amount of foaming agent used,the more residual amount of formamide.The treatment of foam sheets under different storage conditions(storage temperature and time)will have a significant impact on the residual amount of formamide.With the extension of storage time,its content shows a significant downward trend.The supercritical foaming process can significantly reduce the content of formamide in biobased/EVA products.There is a small amount of formamide in relevant EVA foaming shoe materials,but it will not cause the formamide content in the product to exceed the specified limit.