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The influence of boric acid (BA) and borax (BO) neutron‐absorbing fillers on thermal stability and viscoelastic behavior of natural rubber (NR) low‐density polyethylene composites has been studied. The thermal degradation and dynamic mechanical properties of the composites have been analyzed as a function of temperature. The results revealed the enhancement of thermal stability of the composites by the addition of BA and BO fillers. The flame resistance of the material was improved by the addition of both the fillers. The storage modulus was found to be dependent upon the temperature and nature of the filler. The amount of NR chains immobilized by filler particles has been quantified from dynamic mechanical analysis and secondary filler/filler interactions have been verified by the Payne effect analysis. Finally, the experimental results have been compared with theoretical predictions.

Recycled plastic (rHDPE) was coupled with different weight percentage of ronier palm leaf fiber (RLFs) to prepare eco‐friendly polymer biocomposites. Fourier transform infrared analysis, tensile test, dynamic rheological test, hardness test, scanning electron microscopy (SEM) analysis, and density measurement were used to determine the structural, mechanical, morphological and physical properties of the biocomposites. The modulus showed excellent improvement with the addition of RLFs. G′ and G″ were found to increase with the increment of both the filler content and the angular frequency. At low frequencies, the loss factor was increased with the frequency and decreased with the RLFs content. However, at high frequencies, it was decreased with both the angular frequency and the RLFs content. The complex viscosity η* was found to be increasing and decreasing with the RLFs content and the angular frequency, respectively. SEM micrographs of tensile fractured surfaces of biocomposites show pulled out RLFs zones and voids due to the presence of agglomeration. Finally, the experimental Young's modulus data was compared with theoretical predictions. A good fit was obtained with Einstein Model.

Flexible polymer composites have been the focus of demanding interest in classical studies of neutron radiation shielding applications. The influence of varied loading of carbon black on the morphology, mechanical and neutron shielding properties of Ethylene Diene Monomer Rubber/High-Density Polyethylene (100/30) blends are observed through this experimental work. EPDM and HDPE were blended in a Brabender type internal mixer and other functional additives were dispersed using two roll mill and later cured using a compression molding, on determining the cure time on rubber rheometer. The carbon black addition enhanced HDPE dispersion in the EPDM matrix, as evidenced through morphological and mechanical analysis. The improvement in the tensile parameters indicates the reinforcing efficiency of the carbon black in EPDM/HDPE blends. Lower tear resistance suggests a weak interface within the EPDM / HDPE blend at low black carbon concentration. Carbon black filled EPDM/HDPE composites displayed a total neutron macroscopic cross-section of 0.28 cm−1 for 2 MeV energy neutrons.