摘要
采用熔融共混制备了聚对苯二甲酸丙二酯(PTT)/聚对苯二甲酸丁二酯(PBT)共混体系以及碳纳米管(CNTs)填充改性的三元复合体系,通过核磁共振波谱仪(NMR)研究了CNTs对共混基体组分间酯交换反应的影响,并结合透射电子显微镜(TEM)、沉降实验等多种测试结果初步探讨了影响的机理.研究结果表明,PTT/PBT为典型的热力学相容体系,少量原钛酸丁酯(Ti(OBu)4)能够有效地催化体系两组分间发生酯交换;而共混过程中CNTs的加入则进一步促进了酯交换反应,导致共聚酯序列长度(LB和LT)显著下降,体系无规度(B)升高,意味着CNTs能够催化甚至参与酯交换反应;不过CNTs的这种促进作用具有含量的依赖性,随其含量增加体系的酯交换度(Y)逐渐降低.
Poly（trimethylene terephthalate）（PTT）/poly（butylene terephthalate）（PBT） blend and its ternary systems reinforced by carbon nanotubes（CNTs） were prepared by melt-mixing.The effect of CNTs on the transesterification between PTT and PBT was then studied through nuclear magnetic resonance spectroscopy（NMR）.The possible mechanisms were then discussed preliminarily according to the observations by transmission electron microscopy（TEM） scanning electron microscopy（TEM） and sedimentation experiments,as well as the results from other measurements such as rheology and dynamical thermal mechanical analysis（DTMA）.The as-obtained PTT/PBT is a typical thermodynamical miscible blend system and,small amounts of tetrabutyl orthotitanate（Ti（OBu）4） can promote ester inter-change reactions between PTT and PBT components effectively.The addition of CNTs during melt mixing can further facilitate transesterification in the systems,resulting in evident decrease of the number-average length（LB and LT） of PTT-PBT copolymers and increase of the degree of randomness（B） of systems.This indicates that the CNTs can catalyze or even participate in the ester inter-chain reactions in the ternary systems.Such an effect,however,shows high dependence on the CNT loadings.With increasing CNTs loadings,the transesterification degree（Y） of ternary systems reduces gradually.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2011年第12期1425-1432,共8页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号50803052)
江苏省自然科学基金重点项目(基金号BK2010040)资助
