[en] Phenol formaldehyde (PF) resin has been extensively used in various branches of industry as adhesive especially in the production of wood-based panels. However, due to the use of expensive and limited petroleum-based phenol in its formulation, there is a strong interest to explore renewable biomass material to partially substitute the phenol. In this work, slow pyrolysis was used to convert oil palm frond into bio-oil. From there, the phenol-rich fraction of the bio-oil was separated and added into the formulation of PF resin to produce an economical and environmental-friendly type of PF resin, known as bio-oil-phenol-formaldehyde (BPF) resin. Rhizophora particleboard was then fabricated with the BPF resin as adhesive. The particleboard was found to display excellent mechanical and physical properties with satisfactory formaldehyde emission. A morphological study of the particleboard also supported previous findings. The corresponding atomic number of the particleboard obtained from the morphological study was compared with those of water phantom and a fascinatingly favourable similarity was observed. This finding, hence, proposed a novel higher value-added application of the Rhizophora particleboard which has been largely researched as a potential phantom material in diagnostic radiography. (author)

[en] The composite polymer films of poly pyrrole-poly(vinyl alcohol)-iron chloride were prepared in the form of as-cast films. The dielectric properties of the samples were measured at the frequency range of 20 Hz to 1 MHz at different temperatures (300 K up to 353 K) by Inductance Capacitance Resistance (LCR) meter. The results show that the dielectric properties were strongly dependent on the variation of temperature applied. The composite polymer films exhibit the combination of intrinsic dielectric anisotropy, as a result of the competition of free charges, mainly between the polaron in poly pyrrole and the electronic polarisation that corresponded to PVA matrix. The main mechanism behind this finding can be explained by the dipole movement which highly activate at higher temperatures. In addition, high mobility of dipoles movement induced by thermal energy enables them to easily orient towards applied electric field. (author)

[en] The composite polymer films of polyvinyl alcohol/polypyrrole/chloral hydrate (PVA-PPy-CH) had been prepared. Effects of γ-rays on the electrical conductivity of the composite polymer films had been investigated by using Inductance Resistance meter (LCR) meter at a frequency ranging from 20 Hz to 1 MHz. With the incorporation of choloral hydrate in the polymer sample, the conductivity increased indicates that it is capable to be used as dopant for polymerizing conjugated polymer. The electrical conductivity obtained increased as the dose increased, which is in the order of 10^-5 Scm^-1 indicates that γ-ray is capable to enhance the electrical conductivity of the composite polymer films. The parameter of s is in the range of 0.31 ≤ S ≤ 0.49 and obeyed simple power law dispersion ω^S. The Scanning Electron Microscopy (SEM) micrographs reveal the formation of polypyrrole globules in polyvinyl alcohol matrix which increased as the irradiation dose was increased. (Author)