|Institution:||University of Birmingham|
|Department:||School of Metallurgy and Materials|
|Keywords:||TP Chemical technology|
|Full text PDF:||http://etheses.bham.ac.uk/5809/|
Most polymer materials used currently in industry have high viscosity, so it is difficult to make a composite. But unlike other common polymers, the viscosity of cyclic poly (butylene terephthalate) oligomers (CBT) is like water. This interesting performance gives CBT a promising future in polymer composite production. It is believed that carbon nanotubes promote high stiffness and strength in materials as they act as reinforcing filler in nanocomposites. In this work, multiwalled carbon nanotubes (MWNTs) were blended with cyclic poly (butylene terephthalate) by a new method. The materials were mixed in solid dispersion and prepared by simultaneous in situ polymerisation. It was found that the polymerisation and crystallisation of CBT occurs simultaneously and rapidly in a short time. The presence of multiwalled carbon nanotubes increases crystallinity of composites dramatically, but after adding MWNTs, the Young's modulus of the nanocomposites decreased. It is suggested that a crystalline structure makes the material less stiff. Although the fracture surface were not clearly under a scanning electron microscope, it is expected that carbon nanotubes dispersed homogenously at low weight percentage, but agglomerated when the proportion rose above 0.8wt%.