Investigation on the Effect of NiZn Ferrite on the Mechanical and Thermal Conductivity of PLA/LNR Nanocomposites

The mechanical and conductivity of magnetic polymer nanocomposite (MPNC) of nickel zinc (NiZn) ferrite nanoparticles incorporated with poly(lactic acid) (PLA) and liquid natural rubber (LNR) as compatibilizer is reported. The matrix was prepared from PLA and LNR in the ratio of 90 : 10. The MPNC of PLA/LNR/NiZn ferrite then was prepared via Thermo Haake internal mixer using melt-blending method from different filler loading from 1–5 wt% NiZn ferrite. The result of tensile tests showed that as the filler loading increases, the tensile strength also increases until an optimum value of filler loading was reached. Young’s modulus, tensile strength, and elongation at break have also increased. The study proves that NiZn ferrite is an excellent reinforcement filler in PLA/LNR matrix. The optimum thermal conductivity of PLA/LNR composites achieved with (4 wt% NiZn) due to the effective combination of NiZn-NiZn conductive networks. The scanning electron micrograph (SEM) reveal that the aspect ratio and filler orientation in the PLA/LNR matrix also strongly promoted interfacial adhesion between the filler and the matrix to control its properties

Sifat magnet, mikrostruktur dan morfologi komposit getah asli termoplastik berpengisi Ferit NiZn/MwNT

Ferit NiZn dan nanotiub karbon diadunkan ke dalam getah asli termoplastik mengikut nisbah campuran 1:1. Kesan penambahan pengisi ke atas sifat magnet, struktur dan morfologi nanokomposit dikaji. Dua parameter magnet, iaitu pemagnetan tepuan dan daya koersif nanokomposit didapati bergantung kepada penambahan pengisi dalam matriks. Interaksi antara kedua-dua pengisi dalam matriks TPNR juga mempengaruh sifat magnet. Pengisi hibrid (ferit NiZn dan nanotiub karbon) bertabur sekata dalam matriks termoplastik getah asli. Kehabluran semi-amorfus fasa polipropilena didapati berlawanan dengan peningkatan kehabluran pengisi apabila kandungan pengisi bertambah

Combination of gamma irradiation and sodium carbonate pretreatment on oil palm Empty Fruit Bunch (EFB) for high acidic hydrolysis yield

Oil palm empty fruit bunch (EFB) fibres were pretreated by gamma irradiation followed by sodium carbonate (Na2CO3) before the acid hydrolysis process to produce reducing sugars using diluted sulphuric acid (H2SO4). In this study, EFB fibres were irradiated at different doses, i.e. 0, 100 and 200 kGy. Meanwhile, the gamma irradiated sample were then subjected to Na2CO3 pretreatment with 0 and 5% total titratable alkali (TTA). The effect of the pretreatment using gamma irradiation and Na2CO3 on the physical and chemical properties of the EFB fibres and the yield of the reducing sugar obtained from the acid hydrolysis process was investigated. The obtained results showed that the content of holocellulose was increased significantly with the increase of irradiation doses combined with Na2CO3 pretreatment, whereas lignin content of the EFB was decreased. The gamma irradiation and Na2CO3 pretreatment resulted in structure breakage and removal of silica of EFB fibres which can be due to the swelling of the fibres. A synergistic effect between gamma irradiation and Na2CO3 was observed, in which the yield of reducing sugars was increased by combining the gamma irradiation and Na2CO3 pretreatment

Structural and magnetic properties of type-m barium ferrite– thermoplastic natural rubber nanocomposites

Structural and magnetic properties of type-M barium ferrite (BaFe12O19) nanoparticles (~ 20 nm) embedded in non-magnetic thermoplastic natural rubber (TPNR) matrices were investigated. The TPNR matrices were prepared from high density polyethylene (HDPE) and natural rubber (NR) in the weight ratios of 80:20 and 60:40, respectively, with 10 wt% of NR in the form of liquid natural rubber (LNR) which act as a compatibiliser. BaFe12O19 – filled nanocomposites with 2 – 12 wt% BaFe12O19 ferrite were prepared using a melt- blending technique. Magnetic hysteresis was measured using a vibrating sample magnetometer (VSM) in a maximum field of 10 kOe at room temperature (25oC). The saturation magnetisation (MS), remanence (MR) and coercivity (Hc) were derived from the hysteresis loops. The results show that the structural and magnetic properties of nanocomposites depend on both the ferrite content and the composition of the natural rubber or plastic in the nanocomposites. All the nanocomposites exhibit an exchange bias-like phenomenon resulting from the exchange coupling of spins at the interface between the core ferrimagnetic region and the disordered surface region of the nanoparticles

Mechanical and thermal properties of palm-based polyurethane composites filled with Fe3O4, PANI and PANI/Fe3O4

In-situ polymerization method was used to prepare palm-based polyurethane (PU) composites loading with 15 wt% magnetite (Fe3O4), polyaniline (PANI) and Fe3O4 coated with PANI labeled as PU15, PP and PPM, respectively. FTIR spectroscopy analysis indicated a shift in the carbonyl, C=O and NH in PP. The shift of the peak indicated that there was hydrogen bonding between the C=O (proton acceptor) of urethane with NH (proton-donator) of PANI. PPM gave the highest impact and flexural strengths at 4875 kJ/ m2 and 42 MPa, respectively but with the lowest flexural modulus (1050 MPa). Two-stage degradation behavior was observed in the TGA thermogram

Mechanical and thermal properties of graphene oxide filled epoxy nanocomposites

In this study, graphene oxide (GO) filled epoxy nanocomposites were prepared using hot pressed method. The GO was produced using modified Hummers’ method. The produced GO at different compositions (0.1, 0.3 and 0.5 wt%) were mixed with epoxy before the addition of hardener using ultra-sonication. The produced epoxy nanocomposites were characterized in terms of mechanical and thermal properties. The mechanical properties of the nanocomposites were significantly enhanced by the addition of GO. About 50% of increment in the flexural strength of the composite sample filled with 0.3 wt% of GO as compared to the neat epoxy sample. However, only slight improvement in the impact strength of the composite were obtained by adding 0.1 wt% of GO

Sonication effect on the mechanical properties of MWCNTs reinforced natural rubber

This study investigated the sonication effect on the mechanical properties of thermoplastic natural rubber (TPNR) nanocomposites reinforced by multi-walled carbon nanotubes (MWCNTs). The TPNR nanocomposites were prepared using the melt blending method from polypropylene, natural rubber and liquid natural rubber as a compatibilizer, respectively, with 1% of MWCNTs. The results showed that a good dispersion on nanotubes was achieved by sonication. An optimal sonication time of 1 h was found to produce nanocomposites with maximum tensile and impact strength. The Young’s modulus, tensile strength, elongation at break and impact strength increased by almost 11%, 21%, 43% and 50%, respectively as compared with a pristine TPNR sample. The effect of sonication was also confirmed by dynamic mechanical analysis, it showed that the storage modulus E0, loss modulus E00 and glass transition temperature (Tg) also increased for all MWCNTs reinforced samples. Scanning electron micrographs confirm the effect of good dispersion of MWCNTs and their interfacial bonding in TPNR after sonication

Mechanical properties and dynamic mechanical analysis of thermoplastic-natural-rubber-reinforced short carbon fiber and kenaf fiber hybrid composites

The hybridization of thermoplastic natural rubber based on carbon fiber (CF) and kenaf fiber (KF) was investigated for its mechanical and thermal properties. Hybrid composites were fabricated with a melt-blending method in an internal mixer. Samples with overall fiber contents of 5, 10, 15, and 20 vol % were subjected to flexural testing, and samples with up to 30% fiber content were subjected to impact testing. For flexural testing, generally, the strength and modulus increased up to 15 vol % and then declined. However, for impact testing, higher fiber contents resulted in an increment in strength in both treated and untreated composites. Thermal analysis was carried out by means of dynamic mechanical analysis on composites with 15 vol % fiber content with fractions of CF to KF of 100/0, 70/30, 50/50, 30/70, and 0/100. Generally, the storage modulus, loss modulus, and tan d for the untreated hybrid composite were more consistent and better than those of the treated hybrid composites. The glasstransition temperature of the treated hybrid composite was slightly lower than that of the untreated composite, which indicated poor damping properties. A scanning electron micrograph of the fracture surface of the treated hybrid composite gave insight into the damping characteristics