碱性条件下玻璃纤维增强聚丙烯的外观变色研究  

Study on Appearance Changes of Glass Fiber Reinforced Polypropylene under Alkaline Conditions

作　　者：尹朝清 YIN Chaoqing(Shanghai Kingfa Science&Technology Co.,Ltd.,Shanghai 201714,China;Shanghai Engineering Research Center of Functionalizing Engineering Plastics,Shanghai 201714,China)

机构地区：[1]上海金发科技发展有限公司,上海201714 [2]上海工程塑料功能化工程技术研究中心,上海201714

出　　处：《塑料工业》2025年第3期118-123,157,共7页China Plastics Industry

基　　金：上海市2022年度“科技创新行动计划”启明星项目(22QB1403500)。

摘　　要：短切玻璃纤维增强聚丙烯广泛应用于清洁电器行业,需要满足高温碱性溶液喷淋冲洗条件下的外观要求,但由于玻璃纤维增强聚丙烯体系中的树脂、相容剂(马来酸酐接枝聚丙烯,PP-g-MAH)以及玻璃纤维在碱性条件下会发生物理或者化学的变化,导致出现黄变、微裂纹等外观缺陷。本文研究了高温(75℃)氢氧化钠溶液浸泡对聚丙烯以及玻璃纤维增强聚丙烯外观的影响,根据颜色模型(L、a、b)色差数据,发现聚丙烯树脂在高温碱性溶液浸泡后会出现明显的黄变。研究了相容剂PPg-MAH的接枝率与质量分数对聚丙烯经高温氢氧化钠溶液处理后外观的影响,PP-g-MAH的接枝率对耐溶剂变色并没有显著影响,而随着PP-g-MAH含量增加,改性聚丙烯抽提后色差小幅度提高。扫描电子显微镜(SEM)的结果表明,在高温碱性溶液浸泡条件下,短切玻璃纤维增强聚丙烯色板表面会出现明显的微裂纹缺陷,导致密度降低,使其外观明显劣化,随着短切玻璃纤维质量分数的增加,树脂的色差先增大后降低。Choped glass fiber reinforced polypropylene is widely used in the cleaning electrical appliance industry,and it needs to meet the appearance requirements under the condition of high temperature alkaline solution spray rinse.However,the appearance of glass fiber reinforced polypropylene may turn yellow and show defects,due to the physical or chemical changes of resins,compatilizer(maleic anhydride grafted polypropylene,PP-g-MAH)and fiberglass under alkaline conditions.The effects of high temperature(75℃)immersion on the appearance of polypropylene and glass fiber reinforced polypropylene were studied.According to the color model(L,a,b)data,polypropylene turned yellow obviously after immersion in high temperature alkaline solution.The effects of the grafting rate and mass fraction of PP-g-MAH on the appearance of modified polypropylene treated with high temperature sodium hydroxide solution were studied.The results show that the grafting rate of PP-g-MAH shows little effects on solvent discoloration resistance,but the color difference increases slightly with the increase of PP-g-MAH content.Scanning electron microscope(SEM)results show that the surface of choped glass fiber reinforced polypropylene color plate has obvious micro-cracks,which leads to the decrease of density and makes its appearance significantly degraded.With the increase of choped glass fiber mass fraction,the color difference increases first and then decreases.

关 键 词：聚丙烯 短切玻璃纤维 马来酸酐接枝聚丙烯 氢氧化钠溶液 色差 

分 类 号：TQ327.1[化学工程—合成树脂塑料工业]