Conductive polymer, polypyrrole (PPy), was synthesized by chemical oxidative polymerization technique for a period of four hours at room temperature using pyrrole monomer (mPPy) in aqueous solution. Different oxidants such as ferric chloride (FeCl 3 ) and ammonium persulphate (N 2 H 8 S 2 O 8 ) and surfactant sodium dodecyl sulphate (C 12 H 25 NaO 4 S) were used. The produced PPy samples were characterized by using different techniques such as the electrical resistivity by four probe technique, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The performance of the oxidants has been investigated and compared. It was found that both oxidants, FeCl 3 and N 2 H 8 S 2 O 8 , have decreased electrical resistivity as a function of temperature, which means increased conductivity. However, FeCl 3 has achieved better performance than N 2 H 8 S 2 O 8 , where it has achieved a lower resistivity of about 60 ohms at room temperature, which indicates higher conductivity of PPy samples with FeCl 3 as an oxidant. Similarly, further investigation of FeCl 3 oxidant has been conducted by varying its concentration, and its influence on the final properties was reported. It has been observed that the morphology of PPy samples has a significant influence on the conductivity. It was found that 0.1 M and 0.05 M concentrations of FeCl 3 oxidant and monomer, respectively, have achieved better thermal stability, which is FeCl 3 /mPPy ratio of 2 as an optimum value. FTIR and XRD results confirmed the structural formation of polypyrrole from pyrrole monomer during the synthesizing process.

In this research work, graphene nanoplatelets (GNP) were selected as alternative reinforcing nanofillers to enhance the properties of polypropylene (PP) using different compatibilizers called polypropylene grafted maleic anhydride (PP-g-MA) and ethylene-octene elastomer grafted maleic anhydride (POE-g-MA). A twin screw extruder was used to compound PP, GNP, and either the PP-g-MA or POE-g-MA compatibilizer. The effect of GNP loading on mechanical and thermal properties of neat PP was investigated. Furthermore, the influence and performance of different compatibilizers on the final properties, such as mechanical and thermal, were discussed and reported. Tensile, flexural, impact, melting temperature, crystallization temperature, and thermal stability were evaluated by using a universal testing system, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). For mechanical properties, it was found that increasing GNP content from 1 wt.% to 5 wt.% increased tensile strength of the neat PP up to 4 MPa. The influence of compatibilizers on the mechanical properties had been discussed and reported. For instance, the addition of PP-g-MA compatibilizer improved tensile strength of neat PP with GNP loading. However, the addition of compatibilizer POE-g-MA slightly decreased the tensile strength of neat PP. A similar trend of behavior was observed for flexural strength. For thermal properties, it was found that both GNP loading and compatibilizers have no significant influence on both crystallization and melting temperature of neat PP. For thermal stability, however, it was found that increasing the GNP loading had a significant influence on improving the thermal behavior of neat PP. Furthermore, the addition of compatibilizers into the PP/GNP nanocomposite had slightly improved the thermal stability of neat PP.

In this study, linear low density polyethylene (LLDPE) was grafted and crosslinked by reactive extrusion melt compounding using different silane concentration with and without the presence of montmorillonite (MMT) nanoclay.The effects of different silane concentration and the addition of nanoclay filler on the degree of crosslinking, mechanical, thermal, rheological, and morphological properties were investigated and reported. Gel content results for all

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Linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) blend at 70/30 wt% ratio respectively was grafted and crosslinked with aluminum hydroxide (ATH) with and without the presence of montmorillonite (MMT) nanoclay using twin screw extruder. The effect of flame retardant ATH loading (5, 10, 15, 20 wt%), with and without the addition of MMT nanoclay, on the mechanical, thermal, rheological, flame retardancy and morphological properties has been studied and reported. The incorporation of ATH filler into crosslinked LLDPE/LDPE blend enhanced all the aforementioned properties; and it was found that increasing ATH content from zero to 20 wt% has improved tensile strength of the virgin LLDPE/LDPE blend by about 16 MPa. However, the addition of MMT nanoclay into the crosslinked LLDPE/LDPE blend with ATH filler, particularly at higher ATH loading (20 wt%), has not significantly increased the tensile strength. Thermogravimetric analysis (TGA) results have shown significant thermal stability improvement for virgin LLDPE/LDPE blend due to crosslinking, increased ATH filler loading, and subsequent addition of MMT nanoclay. However, at onset temperature, lower degradation rate was observed for samples containing higher ATH loading (15 and 20 wt%). At lower frequency region, it was found that the incorporation of higher ATH filler content and MMT nanoclay into crosslinked LLDPE/ LDPE blend have increased the complex viscosity, storage modulus and loss modulus for virgin LLDPE/LDPE. The FTIR results have confirmed that silane crosslinking reaction of the virgin LLDPE/LDPE blend has occurred. The results obtained from flammability test, UL-94 tests, showed that the flame retardancy of virgin LLDPE/LDPE blend has improved significantly due to the higher ATH filler loading, with and without the presence of MMT nanoclay filler. It was found that the higher ATH filler loading (20 wt%), addition of MMT nanoclay and subsequent crosslinking in the virgin LLDPE/LDPE blend have exhibited and achieved the best flame retardancy result for virgin LLDPE/LDPE blend. Furthermore, SEM results have also shown that