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This paper describes the fabrication of polymeric auxetic foam using a quasi tri-axial compression method. In this method, the conversion process is executed by applying a quasi tri-axial compression on conventional closedcell polyurethane foams. In order to achieve optimum auxetic characteristics, the densification points in various directions are evaluated. In addition, the heating time of the compressed foam is also determined and applied to minimize the residual stress due to the volumetric compression. It leads to the fabrication of auxetic foams with achievable maximum re-entrancy and minimum collapsed cells without surface creasing. The results also show that the optimized auxetic foam exhibits isotropic behavior compared to its precursor foam as verified by the morphological analysis. The produced foam has all the desired properties of auxetic foams. The auxetic foam with a negative Poisson's ratio may have a great potential as the supplementary materials in energy absorption and structural applications.

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Conductive polypyrrole (PPy) was synthesized using a chemical polymerization method in aqueous solution. A series of reactions were carried out with different reaction times of 240 mins and 20 mins. All results were compared to find the highest conductivity and yield. The formation of PPy was verified with Fourier transform infrared (FTIR) analysis which has detected the C-N and pyrrole stretching peaks at 1462 cm-1 and 1169 cm-1, respectively, while the x-ray diffraction (XRD) study has shown a broad halo pattern around 25 ̊ related to PPy. The PPy particles sizes of 5-20 microns were measured from the scanning electron microscope (SEM) image. It was found that in the presence of sodium dodecylbenzene sulfonate (DBSNa) as surfactant, the highest conductivity value of 3.18 S/cm and yield of 68% were achieved at 20 mins reaction time and temperature of 0 °C.

A review on the change mechanism of conjugated polymer upon radiation exposure is presented. The change mechanism is mainly focused on the polymer's optical properties instead of its electrical properties. This research explores the effect of ionizing radiation on the optical change of conjugated polymer. This study also reviewed the possibility of using conjugated polymer as a radiation sensor vis‐à‐vis radiation type and the optical response. From material point of view, topochemical reaction, conjugation length and the degree of anisotropy of the conjugated polymer itself were identified as factors affecting the polymer's optical properties. These factors are tunable to meet a required optical degree, thus making the observation using the optical properties of a conjugated polymer possible for a radiation sensing tool. Based on the review, alteration of the factors and its mechanism of change occurs at macromolecular level. Therefore, a material at its smallest size down to a single molecule could be possible for the indication of radiation. Thus, radiation sensor made of nano or micro colloidal conjugated polymer deserves attention for future development. Copyright © 2017 John Wiley & Sons, Ltd.

In polymer chemistry, polyol usually used as starting materials for polyurethane (PU) production in which upon reacted with isocyanate will affect the physical and chemical properties of the obtained PU. Polyols that are mostly derived from petrochemical resources are facing issues such as depletion of petroleum sources as well as the increasing in market price. Ring opening reaction (ROR) of epoxidized palm oil (EPO) had been carried out using isopropanolamine (IPA) to impart polyol with amine functionality. The effect of reaction time on the opening of oxirane ring was investigated. FTIR spectra showed that the oxirane ring opening of EPO can occur at 6 hours reaction time, corresponding to the deacreasing intensity of  oxirane COO twin band at 824-830 cm-1. The OH value of the amine- functionalized-polyol was calculated at around 240-253 mg KOH/g. By prolonging the reaction time the OH value has slightly reduced. Mass spectroscopy analysis revealed that the polyol has a molecular weight in the range of oligo-polyols (400 – 500 Da).