Ethyl vinyl acetate (EVA) copolymers are recyclable plastics with exceptional biocompatibility, thus they are potent candidate materials for biomedical applications. In this study, improvement in the EVA biostability was aimed by the incorporation of hybrid nanofillers. EVA copolymer incorporating 3 wt % organically modified montmorillonite/bentonite (OMMT/Bent) hybrid nanofillers in different ratios (3:0, 2.75:0.25, 2.5:0.5, 2.25:0.75, 2:1 and 0:3 in wt %) were prepared by melt compounding process and then analyzed for their biostability upon in vitro physiological fluid exposure. Results indicated that the addition of OMMT 2.75 / Bent 0.25 hybrid nanofillers can reduce the degradation of the EVA copolymer under physiological fluid environment through hydrophilic bentonite-vinyl acetate interactions. The obtained nanocomposite material achieved the best retention in tensile and thermal properties upon 4 weeks exposure in the in vitro physiological fluid. The findings indicate the potential of using the hybrid OMMT/ Bent nanofillers for biostability enhancement of the EVA while reducing the nanocomposite production costs through the addition of cheaper natural bentonite as co-nanofiller with the OMMT.

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In this contribution, we report the effect of ultrasonication time on thermal stability and swelling of organically modified montmorillonite (O-MMT) upon ultrasonication in a water medium. In the production of well-exfoliated polymer/clay nanocomposite, ultrasonication was employed as a method to exfoliate and disperse organically modified montmorillonite (O-MMT) platelets prior to melt compounding with the polymer matrix. The suspension of distilled water and O-MMT was magnetically stirred for 2 hours and then ultrasonicated at the different sonicating time, namely, 2 minutes, 5 minutes, 10 minutes, 15 minutes and 20 minutes (min) at room temperature. Thermogravimetry analysis (TGA) suggested that dispersion of the O-MMT by ultrasonication for 5 minutes resulted in thermal stability enhancement without destruction of the organic surface modifier structure and bonding on the clay platelets. X-ray diffraction (XRD) also indicated that application of 5 minutes ultrasonication time has most obviously improved the swelling of the O-MMT platelets. This was further proved by Field emission scanning electron microscope (FeSEM) which revealed greater interlayer spacing within the O-MMT platelets was obtained.

Nowadays, there is huge demand for novel materials which are desired for new functions and new technological advancements. All technological demands for new applications cannot be implemented by many of the well-established materials, such as single plastics, metals or ceramics. Hence, engineers and scientists realized that, in comparison with pristine counterparts of material, the mixtures of materials can produce much better properties. Polymer nanocomposites is a new form of materials that resulted by the combination of polymers and nanofillers which contributed to various benefits over the neat polymer such as improvement in biocompatibility, biostability, thermal stability, flame retardancy, mechanical and barrier properties. Due to these factors, nanocomposites have received an extraordinary consideration for use in broad range of applications. However, the polymer nanocomposites which comprised of copolymer as matrix material are not widely studied, especially those involved poly(ethylene-co-vinyl acetate) (PEVA). The production of PEVA copolymer-based nanocomposites for various applications has been reported by few research papers. In this communication, a review on the properties of PEVA-based nanocomposites with different types of nanofiller was summarized, revealing the high potential of this class of nanocomposite for advanced applications.

Fuel cell is one of alternative method to replace fossil fuel energy. The important component of fuel cell is a membrane that used for separating cathode and anode also as a proton conductor. The purpose of this research is to produce polymer electrolyte membrane from poly (eugenol sulfonate) (PES) as polymer matrix, characterize the resulting membrane analysis using ionic properties analysis by calculating ionic conductivity using impedance spectroscopy, ion exchange capacity (IEC), solvent absorption analysis by calculating water uptake and methanol permeability, and studying mechanism Proton transport that occurs on the membrane. This research was initiated by making polymer of PES, and then fabrication and characterization of electrolytic polymer membrane. The formed membrane has an optimal proton conductivity of 0.00095 S.cm-1 with PES composition of 22% (wt).