P34HB的4HB含量对PLLA/P34HB共混物结构和性能的影响  

Effect of 4HB Content of P34HB on the Structure and Properties of PLLA/P34HB Blends

作　　者：李媛媛[1] 钱祉祺[1] 包睿莹[1] 杨伟[1] 杨鸣波[1] 

机构地区：[1]四川大学高分子科学与工程学院高分子材料工程国家重点实验室,四川成都610065

出　　处：《高分子材料科学与工程》2016年第6期96-100,106,共6页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51422305)

摘　　要：采用熔融共混方法制备了聚乳酸/聚(3-羟基丁酸-4-羟基丁酸酯)(PLLA/P34HB)共混物,其中P34HB的4HB摩尔含量分别为11%与17%。通过扫描电子显微镜、动态力学分析、差示扫描量热仪和力学性能测试,考察了共混物的相容性、熔融行为与力学性能。结果表明,当P34HB组分质量分数为25%以上时,共混物两相玻璃化转变温度(Tg)相互靠近,为部分相容体系,且4HB含量越少,PLLA/P34HB共混物的相容性越好。共混物中PLLA的结晶性能随P34HB含量的增加而降低,且4HB含量越大,由于较差的相容性导致P34HB对PLLA的链段运动能力影响减小,共混物中PLLA结晶性能越好。随P34HB含量的增加,共混物的强度降低,断裂伸长率升高,且4HB含量越大,共混物力学性能由于两相相容性较差而低于4HB含量较低的共混体系。The blends of poly（ lactic acid）（ PLLA） and poly（ 3-hydroxybutyrate-co-4-hydroxybutyrate）（ P34HB）with 4-hydroxybutyrate（ 4HB） molar fraction of 11% and 17% were prepared via melt blending. In order to study the effect of 4HB content of P34 HB on the miscibility,melting behaviors and mechanical properties of the blends,scanning electronic microscope（ SEM）,dynamic mechanical analysis（ DMA）,differential scanning calorimetry（ DSC） and mechanical test were used. The results show that the two glass-transition temperatures（ Tg） of PLLA/P34 HB blends get close to each other,meaning that PLLA / P34 HB blend is partially miscible at the content of P34 HB higher than 25%.Besides,the more 4HB content,the better miscibility of PLLA / P34 HB. The crystallization ability of PLLA for PLLA /P34 HB decreases with increasing P34 HB content,and the crystallization ability of PLLA for PLLA / P34 HB with molar fraction 17% 4HB is greater than the one with 11% 4HB due to the inferior miscibility of the former. The tensile strength of PLLA / P34 HB blends reduces and the elongation at break of PLLA / P34 HB blends improves with increasing content of P34 HB. Meanwhile,the mechanical properties of PLLA / P34 HB are lower for the blends with higher 4HB content because of the poorer miscibility.

关 键 词：聚乳酸 聚(3-羟基丁酸-4-羟基丁酸酯) 相容性 力学性能 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]