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In this study, a simple and efficient non-covalent functionalization method was developed to introduce conducting polymer of P3HT onto pristine MWCNT and hydroxyl MWCNT surfaces without causing significant changes in electrical characteristics, especially if used as a sensing material. Electron microscopy (FE-SEM) and (HR-TEM) were used to examine the surface morphology of nanocomposites, which demonstrated that the MWCNTs were well wrapped by P3HT. EDX analysis showed interactions between MWCNT-OH and P3HT, with a higher sulfur content of 7.77 wt% from P3HT. Additionally, the diameters of both pristine MWCNT (24.46 nm) and MWCNT-OH (27.56 nm) increased significantly when they form nanocomposites (35.35 nm and 39.40 nm respectively). Further characterization of the produced P3HT-MWCNT nanocomposite was performed using FT-IR and Raman spectroscopy. It was discovered that MWCNTs were dispersed uniformly, with a substantial interaction between P3HT and MWCNTs. The introduction of malathion on the surface of the nanocomposites reveals interaction between P3HT and malathion via intermolecular hydrogen bonding of thiophene, as evidenced by inelastic neutron scattering (INS) spectroscopy, suggesting that the P3HT/MWCNT has the potential as a promising sensing material for organophosphate compounds detection.

In recent years, serious reduction in petroleum resources and concerns about the usage of synthetic plastics have prompted global communities to accept the use of natural fibres and biopolymers in many products. Lignocellulosic fibre polymer biocomposites have attracted the attention of scientists and engineers because of their wide availability, low carbon emission and biodegradability. Currently, oil palm is one of the main crops cultivated in Malaysia and Indonesia and is regarded as a potential source of lignocellulosic fibres for biocomposites. The cellulosic content of oil palm fibres (OPFs) enhances the mechanical properties of composites. Ensuring the compatibility of OPFs as main constituents with other materials in composites for a specific applications is essential. Mechanical performance in terms of tensile, flexural and impact strength determines an OPF's compatibility. However, no comprehensive reviews focusing on the mechanical properties of OPF biocomposites have been published, and factors influencing mechanical performance, such as interfacial adhesion, stacking sequence, additive, type of polymer and fibre size have not been explored. Some studies have identified the research gaps and deduced that the potential applications of OPFs as reinforcement materials in composites have not been explored.

The effect of layering structures on mechanical and thermal hybrid bacterial cellulose (BC) sheet/Kevlar reinforced epoxy composites was investigated. The BC sheet was extracted from Nata de Coco and used as green reinforcement material hybrid with Kevlar reinforced epoxy composites. The BC/Kevlar reinforced epoxy composite was fabricated by using hand lay-up technique equipped with vacuum bagging system and the BC sheets and Kevlar layers were laminated into different layered structures. The performance of the hybrid BC/Kevlar reinforced epoxy composites was characterized through tensile test and low velocity impact according to ASTM D3039 and ASTM D7136, respectively. The thermal performance of the hybrid composites was characterized by using dynamic mechanical analysis (DMA) test. Tensile test on BC sheet composites with Kevlar and epoxy demonstrated that the addition of BC sheet in BC/Kevlar could not withstand the tensor stress by reducing the tensile stress and Young's modulus. The one layer of Kevlar which was replaced with three to six BC sheets had increased the ability to absorb impact force. The storage modulus (E′) and Tan δ were significantly dependent on the number of BC sheets and its layering structure. The highest value of E′ was observed when BC sheets were arranged alternately with the Kevlar layers. Different damage mechanisms associated with the number of BC sheets and its layered-structure suggested that the BC sheet was functioning as an impact energy absorber as well as strengthening fibers. This study will upsurge interest in BC reinforced composites and the development of new ideas in automotive, marine and bullet applications.