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Rubber latex industry has been looking for techniques to rapidly estimate the dry rubber content (DRC) of rubber latex with accuracy, at a low cost, and to be used by non-technical people in the field. The basis of electrical charge in terms of proton-electron transfer (P.E.TF) was used to develop a new prototype. The prototype was created with the P.E.TF system, two electrode probe detectors, and a new code program on Arduino board. The data was collected using the P.E.TF system of fresh natural rubber latex and presented as the P.E.TF number and the percentage of dry rubber content (%DRC). The standard method (ISO126:2005(E)) was used to calculate %DRC. The comparison of the %DRC measurement using the prototype and the standard method was studied. It was found that the new code program on Arduino board could evaluate the data. In real-time, it converted the P.E.TF number into %DRC on the LCD screen. The %DRC measurement using the prototype was close to that calculated using the standard method. The correlation between the two methods is 0.9814 of Rsqr. Therefore, the novel measurement system can replace the standard method for the %DRC measurement of fresh natural rubber latex. The prototype is simple, fast to detect, small, and low-cost without operator training.

Raman spectroscopy including mapping technique appears as a powerful technique for the characterization of polymer blends like thermoplastic elastomers (TPEs) and thermoplastic vulcanizates (TPVs). The Raman spectra of polymers blends such as natural rubber/polypropylene (NR/PP) and 65% hydrogenated natural rubber/polypropylene (65%HNR/PP) were identified and the phase distribution was determined. The study was driven for the same type of blends in TPEs state and TPVs state obtained after to 2 different processes, either peroxide cure or sulfur cure. The morphology of TPEs and TPVs obtained by Raman spectroscopy were compared and confirmed using scanning electronic microscopy. Raman mapping shows that the phase morphology of NR/PP, 65%HNR/PP, were characterized as continuous rubber phase morphology of the thermoplastic elastomers (TPEs) and a fine dispersion of cross-linked rubber phase in a continuous matrix of the thermoplastic vulcanizates (TPVs). Raman spectroscopy is demonstrated to be a reference to determine the content ratio of each component in the TPVs. Moreover, Raman mapping could be used to calculate the phase size of cross-linked rubber phase dispersed in the thermoplastic vulcanizates (TPVs).

The Pascal’s law is a part of physics subject which difficult for students to imagine and understand. Therefore, the aim of this work is to help the students to easily understand the Pascal’s law via studying the effect of fluid volume on movement joint mechanisms degree and applying to build a reuse material robotic as effective physics leaning media. The process start with teaching the students about the Pascal’s law. After that, encouraged the students to test the effect of fluid volume to each joint movement. Finally, they can assemble each component to build a movement robot. It was found that the students can understand the Pascal’s law after studied and analyzed the effect of fluid volume on join movement of each part of the robot. This knowledge helped student to build a robot that can successfully move by the Pascal’s law. Thus, this leaning media is an important development leaning skill of students about the Pascal’s law in physics.

The ozone stability of partially hydrogenated natural rubbers (HNRs) was evaluated. HNRs with the hydrogenation levels of 14, 33 and 65 mol% including with vulcanization systems of peroxide and sulfur on ozone stability comparing with natural rubber (NR) and ethylene-propylene-diene-rubber (EPDM) vulcanizates were studied. The chemical structures of rubber vulcanizates were characterized by Raman spectroscopy. The surface cracks were observed by Raman optical microscopy. The results clearly exhibited that the ozone stability of HNRs vulcanizates was much greater than that of the NR vulcanizates. The difference between the integral intensities of C=C bonds of isoprene units in rubber chains by Raman spectroscopy before and after ozone exposed was minimized with the degree of hydrogenation. The depth of cracking observed by three-dimensional (3D) modes clearly decreased with an increase in the degree of hydrogenation, while no cracks on the surface of EPDM were found. These findings indicated that ozone stability increased with the degree of hydrogenation. Regarding the effect of vulcanizing systems, sulfur cure showed greater resistance to ozone degradation than peroxide cure.