In this paper, firstly, new Hermite–Hadamard type inequalities for harmonically convex functions in fractional integral forms are given. Secondly, Hermite–Hadamard–Fejer inequalities for harmonically convex functions in fractional integral forms are built. Finally, an integral identity and some Hermite–Hadamard–Fejer type integral inequalities for harmonically convex functions in fractional integral forms are obtained. Some results presented here provide extensions of others given in earlier works.

The production of petroleum‐based polymers in huge amounts is perilous for our ecosystem and oil reserves. The use of biodegradable polymers instead of synthetic polymers for various commodity, engineering, and biomedical applications remains the overriding concern of the researchers in last decades. Although poly(lactic acid) (PLA) is considered to be the most befitting substitute for conventional petroleum‐based products because of its superlative mechanical properties, material & processing cost, and non‐toxicity, they have some consequential limitations for various applications because of their slow rate of crystallization, low thermal stability, high brittleness, and low toughness. To overwhelm these deficiencies during the last two decades, researchers have developed various techniques to tailor the properties of PLA, that is, blending with other polymers or using additives such as nanofillers. Among all the nanofillers, for example, carbon nanotubes and organoclays, polyhedral oligomeric silsesquioxanes (POSS) was found the most promising nanofiller because of its organic and inorganic nanostructure and fine dispersion into PLA matrix. This article reviews all the investigations relevant to POSS incorporation into PLA or blends of PLA with other polymers to compare the mechanical, morphological, and physical properties of the ameliorated composites and the neat PLA.

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The effect of octavinyl-polyhedral oligomeric silsesquioxane (OV-POSS) on the cross-linking, cure kinetics, and adhesion properties of natural rubber (NR)/textile cord (aramid, nylon 6.6, and polyester) composites was investigated in this study. OV-POSS could directly accompany the vulcanization reaction, thanks to its multiple vinyl groups. It was observed that incorporation of OV-POSS into the reference NR compound (REF) delayed the curing time and reduced the cross-linking density. Thermal gravimetric analysis revealed that OV-POSS improved the thermal stability of NR. NR/OV-POSS composites including 1 and 3 phr OV-POSS exhibited similar elongation at break and tensile strength values as compared to the REF compound. Adhesion characteristics of the compounds have been investigated in terms of strip H-adhesion test, and thermodynamic energy of adhesion was determined by contact angle measurements. It was observed that the addition of OV-POSS to the NR compound improved the interfacial adhesion significantly between NR and aramid and NR and nylon 6,6 fibers.

The research and development (R&D) in rubber formulation development require reproducible, repeatable, fast, accurate, and efficient sample preparation. The lab-scale formulation development is conventionally carried out using small-scale internal mixers and two-roll mills. However, high torque laboratory twin-screw micro-compounder, which have been serving the plastic industry for more than 30 years, can be used to formulate new rubber compounds for fast and accurate sample preparation that on top can contribute to the economics of R&D. In this study, we investigated the possibility of using lab-scale 15 mL high torque twin-screw micro-compounder as a tool for new rubber compound development. For this purpose, we formulated EPDM/carbon black and EPDM/silica recipes through conventional way using a Banbury mixer followed by a two-roll mill, and through the possible way using a lab-scale 15 mL twin-screw micro-compounder. We crosslinked both systems via hot press at a predefined temperature and time. The rheological and mechanical properties of the compounds were investigated. Moreover, the dispersion of carbon black and silica in the EPDM matrix was judged by DisperGrader and scanning electron microscope (SEM). The conventional way of sample preparation was compared with a possible sample preparation method based on materials’ parameters and ease of operation.