丙烯酸酯三嵌段热塑性弹性体增韧有机玻璃

Toughening of Poly(methyl methacrylate)by Acrylate Triblock Thermoplastic Elastomers

研究了甲基丙烯酸甲酯(MMA)-丙烯酸丁酯(BA)三嵌段热塑性弹性体(PMBM)对有机玻璃的冲击强度及其他性能的影响。加入少量链段组成为6k_(PMMA)-53k_(PBA)-6k_(PMMA)的PMBM能明显提高有机玻璃的冲击强度,当加入量为3%时,增韧效果最佳,冲击强度达到4.76kJ/m^2,提高了126%。当PBA段长度固定时,不同PMMA链段质量含量对增韧效果也有很大影响,当PMMA链段质量分数为42.5%,增韧效果最佳,冲击强度提高了86%。通过扫描电镜分析表明PMBM/有机玻璃共混物的断裂面表现出典型的韧性断裂特征。通过动态力学分析、透光率测试表明,PMBM的加入对有机玻璃的耐热性、光学性能影响很小。

The effects of poly （methyl methacrylate-b-butyl acrylate-b-methyl methacrylate） （PMBM） on the impact strength and other properties of poly （methyl methacrylate） （PMMA） were investigated in this work. Low addition level of PMBM with composition of 6kpMMn-53kpea-6kpMMa has remarkable imprpvement on the impact resistance of PMMA. The highest impact strength of 4.76 kJ/m2 with increase of 126% relative that of PMMA is achieved by addition of 3 % PMBM. The mass fraction of PMMA segment in PMBM also exhibits great effect on the impact resistance of PMMA when the mass fraction of PBA is kept constant. The highest impact strength increase of 86 % relative to that of PMMA is achieved when the mass fraction of PMMA segment is 42.5 %. Scanning electron microscope analysis reveals that the impact fracture surface of PMBM/PMMA blends exhibits ductile fracture characteristic. The heat resistant and transmittance properties are changed little by addition of PMBM as revealed by dynamic thermomechanical analysis and transmittance spectrometer.