Abstract:
Research into and devolvement of single polymer composites (SPCs) have increased consistently over the last decade, due to growing concerns for the environment. SPCs are an emerging class of materials of composites which have improved mechanical properties compared with their larger homogeneous counterparts. These SPCs have economic and environmental benefits and are fully recyclable. This research aimed to produce fibrillar SPCs of low linear density polyethylene (LLDPE), polypropylene (PP) (lower melt flow grade) and carbon nanotubes loaded poly(butylene terephthalate) (PBT-CNT) by using the concept of microfibrillar reinforcement composites (MFCs) manufacturing technique via a simple extrusion, drawing and processing technique. Microfibrillar single polymer composites (MF-SPCs) were prepared by the hot-compaction of PBT-CNT, LLDPE and PP555G fibrils extracted by using selective solvents from the immiscible drawn blends of PP (higher melt flow grade)/PBT-CNT, polyvinyl alcohol (PVA)/LLDPE and PVA/PP555G respectively, and were then characterised by their thermal, morphological, mechanical, and electrical behaviour (only for PBT-CNT MF-SPCs samples). LLDPE MF-SPCs and PP555G MF-SPCs can potentially be used in automotive and construction, and consumer products such as suitcases and sporting apparel. The resulting uniaxial composites showed excellent improvements in stiffness of 65% for PBTCNT (30%) MF-SPCs, 194% for PBT-CNT (50%) MF-SPCs, 307% for LLDPE MF-SPCs and 367% for PP (lower melt flow grade) MF-SPCs over their respective neat isotropic PBT-CNT, LLDPE and PP samples. The microfibrillar structure and excellent orientation with high aspect ratios were maintained and observed using scanning electron microscopy (SEM). PBT-CNT MFSPCs demonstrated moderately electrical conductive behaviour, which probably could be used in a variety of industrial applications such as in sensors, self-regulating heaters and electromagnetic interference shielding. The thesis concludes with suggestions for further research in the future, based on the findings of this study.
