ABS湿热海洋大气环境室内外老化行为及相关性研究

Indoors and Outdoors Aging Behavior and Correlation Research of ABS in Humid and Hot Marine Atmospheric Environment

目的研究丙烯腈(Acrylonitrile)、丁二烯(Butadiene)、苯乙烯(Styrene)3种单体的三元共聚物(Acrylonitrile-Butadiene-Styrene,ABS)在湿热海洋大气环境室内外的老化行为及其相关性。方法开展湿热海洋大气暴露(室外)试验及多因子循环加速老化(室内)试验,通过观测外观形貌、力学、化学结构等性能变化,定性探究ABS室内外老化规律。通过灰色关联度与主成分分析,定量探索ABS室内外老化行为的相关性。结果ABS黄色指数等与表面性能相关的指标在户外暴露6个月及室内加速老化300 h左右就基本达到饱和值50和45,而与整体性能相关的拉伸强度在老化过程中先下降、后上升,断裂伸长率、冲击强度、缺口冲击强度等指标在户外暴露2个月或室内老化200 h快速下降近60%后,再缓慢降低。分子链中丁二烯单体的双键或苯环侧链中的季碳受到环境中光、氧、水等的作用,分解生成酮与羟基。通过主成分分析,将ABS多种性能指标组合成综合老化指标,客观定量评价ABS室内外老化灰色关联度高达0.93。结论ABS老化是分子链断链及交联的动态竞争过程,湿热海洋大气环境室内外老化行为的相关性较高。

This paper is to study the aging behavior and its correlation between the ABS(Acrylonitrile-Butadiene-Styrene)of three monomers,that is,acrylonitrile,butadiene,and styrene,indoors and outdoors in a humid and hot marine atmospheric environment.Humid and hot marine atmospheric exposure(outdoor)tests and multi-factor cyclic accelerated aging(indoor)tests were conducted to qualitatively explore the indoor and outdoor aging behavior law of ABS through properties changes such as appearance,morphology,mechanics,and chemical structure,etc.and to quantitatively explore the correlation between indoor and outdoor aging behavior of ABS through Gray Relation Degree and Principal Component Analysis(PCA).ABS yellow index and other indicators related to surface properties basically reach saturation values of 50 and 45 after 6 months of outdoor exposure and 300 h of indoor accelerated aging;while tensile strength related to overall properties first decreases and then increases during aging,and indicators such as elongation at break,impact strength,and notched impact strength,etc.decrease rapidly by nearly 60%after 2 months of outdoor exposure or 200 h of indoor aging,and then slowly decrease.The change is smooth during the environmental test;the double bond of the butadiene monomer in the molecular chain or the quaternary carbon in the side chain of the benzene ring is decomposed to produce ketones and hydroxyl groups by the action of the environment such as photo-oxygenated water.A variety of ABS properties indicators were combined into a comprehensive aging indicator through PCA to objectively and quantitatively evaluate the Gray Relation Degree of ABS indoor and outdoor aging up to 0.93.ABS aging is a dynamic competitive process of molecular chain breaking and cross-linking,and the correlation between indoor and outdoor aging behavior in humid and hot marine atmospheric environment is high.