EVAC对PHB/PCL共混物性能的影响  

The Effect of EVAC on Mechanical Properties and Characteristics of PHB/PCL Blends

作　　者：张豪 张晨清 陈程 陈海英 卫灵君 金光远 Zhang Hao;Zhang Chenqing;Chen Cheng;Chen Haiying;Wei Lingjun;Jin Guangyuan(Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology,School of Mechanical Engineering,Jiangnan University,Wuxi 214122)

机构地区：[1]江苏省食品先进制造装备技术重点实验室,江南大学机械工程学院,江苏无锡214122

出　　处：《工程塑料应用》2022年第10期8-15,共8页Engineering Plastics Application

摘　　要：以乙烯-醋酸乙烯酯共聚物(EVAC)为增容剂,添加到聚羟基丁酸酯(PHB)/聚己内酯(PCL)(质量比为75∶25)二元混合体系中,以溶液浇铸法制成薄膜,探究不同质量比的EVAC(3%,5%和7%)对PHB/PCL共混物薄膜力学性能及理化特性的影响。拉伸试验结果表明,3%EVAC的添加能有效改善PHB/PCL共混物的韧性,其断裂伸长率是对照组的8.6倍。X射线衍射结果表明,加入EVAC后共混物的晶面间距减小,相对结晶度降低。差示扫描量热和热重分析显示,EVAC降低了共混物中PHB的玻璃化转变温度,限制了PHB链的流动性,结晶度降低,而PCL链结晶度增加,此外,EVAC(质量分数为3%)可以改善PHB/PCL(质量比为75∶25)共混体系的总体热稳定性。衰减全反射傅里叶变换红外光谱显示,三元共混物内EVAC的羰基(C=O)吸收峰消失,EVAC与PHB或PCL发生了酯交换反应。扫描电子显微镜显示,EVAC降低了共混体系中PCL分散相的尺寸,共混体系形态由不混溶转换成均相结构,有效改善了两相的界面相容性。As a compatibilizer,ethylene vinyl acetate copolymer(EVAC) was added to the polyhydroxybutyrate(PHB)/polycaprolactone(PCL)(mass ratio is 75∶25) binary blend system and then made films by solution casting.The effects of different mass ratios of EVAC(3%,5% and 7%) on the mechanical and physicochemical properties of the PHB/PCL blend films were also investigated.The results of the mechanical tests show that the addition of 3% EVAC effectively improve the toughness of the PHB/PCL(mass ratio is 75∶25) blends,and its elongation at break is 8.6 fold higher than that of the control group.The X-ray diffraction results show that the addition of EVAC reduce the crystalline spacing and relative crystallinity of the blends.The differential scanning calorimetry and thermogravimetric analysis show that EVAC decrease the glass transition temperature of PHB in the blends,restrict the mobility of PHB chains,and reduce the crystallinity.The attenuated total reflection Fourier transform infrared spectroscopy spectra show that the carbonyl(C=O) absorption peak of EVAC disappear in the ternary blends and EVAC undergo an ester exchange reaction with PHB or PCL.Scanning electron microscope show that EVAC reduce the particle size of PCL disperse phase in the composites,and the morphology of the composites is converted from immiscible to homogeneous structure,which effectively improve the interfacial compatibility of the two phases.

关 键 词：聚羟基丁酸酯 聚己内酯 乙烯-醋酸乙烯酯共聚物 相容性 韧性 

分 类 号：TQ316.6[化学工程—高聚物工业]