聚丙烯酸酯改性纤维素基脲醛树脂模塑料性能研究  

Plastics Performance of Cellulose Based Urea-formaldehyde Resins Modified by Poly( MMA-BA-MAA) Copolymer

作　　者：刘娟[1] 南静娅[1] 王春鹏[1,2] 刘玉鹏[1] 陈日清[1,2] 

机构地区：[1]中国林业科学研究院林产化学工业研究所,生物质化学利用国家工程实验室,国家林业局林产化学工程重点开放性实验室,江苏省生物质能源与材料重点实验室,江苏南京210042 [2]中国林业科学研究院林业新技术研究所,北京100091

出　　处：《林产化学与工业》2015年第2期55-61,共7页Chemistry and Industry of Forest Products

基　　金：中国林科院林业新技术所基本科研业务费专项资金(CAFINT2010K04)

摘　　要：以甲基丙烯酸甲酯(MMA)、丙烯酸正丁酯(BA)和α-甲基丙烯酸(α-MAA)为单体,通过种子乳液聚合制备了聚丙烯酸酯乳液共聚物(PMBM),研究了PMBM玻璃化温度(Tg)分别为80、60和40℃的S1、S2和S3及添加量对纤维素基脲醛树脂模塑料的收缩率、力学性能及热稳定性能等影响,并采用动态力学机械分析(DMA)和电镜扫描(SEM)研究了改性前后脲醛树脂模塑料动态力学性能和冲击断面的微观结构。结果表明,玻璃化温度为40℃的PMBM(S3)对脲醛树脂模塑料的增韧效果最好;当S3添加量为20%时,脲醛树脂模塑料韧性最好,其模塑料收缩率为0.23%,冲击强度为2.47 k J/m2,弯曲强度为75.16 MPa,其中冲击强度和弯曲强度分别比未改性的脲醛树脂模塑料提高了44.4%和39.0%;添加PMBM会降低脲醛树脂模塑料体系的热失重速率,模塑料耐低温性能得到提高。由DMA测试结果可知,S3对模塑料的增韧效果显著,且与脲醛树脂的相容性较好;此外,由SEM分析可知添加20%S3增韧的模塑料断面粗糙,断口光滑,趋于韧性断裂。Polyacrylate emulsion copolymer （PMBM） was prepared by seeded emulsion polymerization with methyl methacrylate （MMA） ,n-butyl acrylate （BA） and methyl acrylic acid （MAA） as monomers, which was used as toughening modifier for cellulose based urea-formaldehyde （UF） resin molding compound. The effects of PMBM＇ s glass transition temperature and contents on the mechanical properties, thermal stability and molding shrinkage rate of the compound were investigated. Moreover, the dynamic mechanical properties and microstructure of fracture surface were studied with dynamic mechanical analysis （DMA） and scanning electron microscope （SEM）. The results showed that the toughening effect of PMBM （ S3 ） with Tg of 40 ℃was the most significant. The toughness of the modified system with 20 % PMBM was the best, and the shrinkage rate was 0.23%. And the impact strength and bending strength were 2.47 kJ/m2 and 75. 16 MICa, which were increased by 44.4% and 39.0% compared with those of the unmodified system, respectively. Thermal weight loss rate of molding plastic could be reduced by adding PMBM, so the thermal stability was improved. The DMA test results showed that S3 had the remarkable toughening effects on the molding compound, and its compatibility with urea-formaldehyde resin was better. In addition, fracture surface of molding compound modified with 20% S3 appeared as ductile fracture.

关 键 词：聚丙烯酸酯 纤维素基脲醛树脂 模塑料 增韧改性 力学性能 热稳定性 

分 类 号：TQ35[化学工程]