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本实验主要针对POE和SBS都能共混增韧PLA的问题,采用聚烯烃弹性体(POE)和苯乙烯-丁二烯-苯乙烯嵌段共聚物(SB

来源:学生作业帮 编辑:搜狗做题网作业帮 分类:英语作业 时间:2024/04/29 15:49:15
本实验主要针对POE和SBS都能共混增韧PLA的问题,采用聚烯烃弹性体(POE)和苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)共同对聚乳酸(PLA)进行增韧改性,将所得共混物性能作比较.主要内容如下:
通过熔融共混、压制片材、冲切试样,测定试样力学性能和流变性能,研究不同含量的POE和SBS对复合材料的性能的影响.借助熔体流动速率(MFR)仪、扫描电子显微镜(SEM)等现代测试手段考察了POE/PLA复合材料和SBS/PLA复合材料的熔体黏度、拉伸性能、冲击强度以及微观形貌.结果表明,随着POE和SBS的含量增加,POE/PLA复合材料和SBS/PLA复合材料的拉伸强度都呈现下降的趋势;断裂伸长率都呈现上升的趋势;冲击强度则是POE/PLA复合材料先增加再下降,SBS/PLA复合材料先显著增加最后逐渐趋于平衡;POE和SBS的加入会改变PLA熔体的流动速率,使其加工和成型温度要低于PLA的熔融温度.随着POE和SBS用量的增加,POE/PLA复合材料的熔体流动速率从26.772 g/10min降低到17.728g/10min,加工性能变好;SBS/PLA复合材料的熔体流动速率从17.208g/10min降低到1.496g/10min,减幅超过10倍,体现优良的易加工性;SEM观察发现,POE和SBS在基体中都具有良好的分散性,且与PLA之间具有较好的界面结合;得出POE和SBS都可以增韧PLA,且相同条件下,SBS增韧效果优于POE增韧效果.
本实验主要针对POE和SBS都能共混增韧PLA的问题,采用聚烯烃弹性体(POE)和苯乙烯-丁二烯-苯乙烯嵌段共聚物(SB
This experiment can be for the POE and SBS Toughening PLA of the problem,polyolefin elastomer (POE) and styrene - butadiene - styrene block copolymer (SBS) common to polylactic acid (PLA) for toughening the resulting blends were compared.Following major elements:
By melt blending,press sheet,punching specimen measured mechanical and rheological properties of samples to study different content of POE and SBS on composite properties.With a melt flow rate (MFR),scanning electron microscopy (SEM) and other modern means of testing examines the POE / PLA composites and SBS / PLA composite melt viscosity,tensile properties,impact strength and microstructure.The results show that,with POE and SBS content increased,POE / PLA composites and SBS / PLA composite tensile strength are showing a downward trend; elongation are showing an upward trend; impact strength is POE / PLA composite first increase and then decrease,SBS / PLA composite final first significant increase gradually more balanced; POE and SBS adding PLA will change the melt flow rate,so that processing and molding temperature lower than the melting temperature of PLA.With the increase in the amount of POE and SBS,POE / PLA composite melt flow rate decreased from 26.772 g/10min to 17.728g/10min,processing performance becomes better; SBS / PLA composite melt flow rate of from 17.208g / 10min reduced to 1.496g/10min,by more than 10 times,reflecting the excellent workability; SEM observed,POE and SBS in the matrix have good dispersibility,and with a better interface between the PLA binding; POE and SBS can be obtained toughening PLA,and under the same conditions,SBS toughening effect than POE toughening effect.