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Showing posts from December, 2020

Wishing you Happy and Prosperous New year

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Every end marks a new beginning. Keep your spirits and determination unshaken, and you shall always walk the glory road. With courage, faith and great effort, you shall achieve everything you desire. We Juniper Publishers, Wish you a Happy New Year - 2021.

A Polymethylvinylsiloxane/Low Density Polyethylene Blending Melt: Dynamic Rheological Behavior and Relaxation Time

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   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract The dynamic rheological behavior of a polymethylvinylsiloxane (PMVS)/ low density polyethylene (LDPE) blending melts at 150,180 and 210 ℃ is investigated by small amplitude oscillatory shear on a rotational rheometer. LDPE has higher viscosity than PMVS at three temperatures, which affects the morphology and rheological response of the blends. The LDPE-rich blends have smaller dispersed droplets and longer relaxation time than the PMVS-rich blends. Higher temperature means less viscosity as well as dynamic modulus difference between the LDPE-rich blend and the PMVS-rich blend. Increasing temperature fastens relaxation of polymer samples thus relaxation time at higher temperature is shorter than that at low temperature. Phase separation can be shown at some weight ratio of PMVS/LDPE through the failure of time-temperature superposition principle and double peaks of relaxation time including the form relaxation time pe

Polyurethane: Recent Engineering Contributions

       JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Polyurethane is one of the most versatile polymers which stands out with a wide range of tunable properties such as chemical stability, flexibility, abrasion and scratch resistance, toughness and biodegradability. It is a unique polymer containing alternating soft and hard segments. This review covers the most recent (2018-2019) engineering research contributions done for the synthesis, properties and applications of the polyurethane foams, coatings, adhesives, sealants, elastomers, composites and insists on the important aspects and realizations related to the polyurethane flammability and acoustic. Keywords:  Polyurethane Synthesis; Applications; Properties; Flammability; Acoustics Abbreviations:  AC: Alternative Current; BPAF: 4,4’ [2,2,2,-trifluoro-1-(trifluoromethyl)ethylidene] bisphenol; CNT: Carbon Nano tube; DAP: Dimer fatty acid band polyol; DC: Direct current; DMA: Dynamic mechanic analysis; DSC: Dynami

Aggregation on the Study of Tribological Properties of Polymer Composites: Molecular Dynamics Simulations

   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract In this study, a brief review of the molecular dynamic’s simulations application in research of tribological properties of polymer composites were presented. To better classify and aggregate, particular attention is given to the frictional factor analysis and the enhancement of polymer composites on the tribological properties. The review of the latest research progress of the tribological research by molecular dynamics simulations and some proposals for further research may have implications for the relevant research and applications, which is practically meaningful and helpful for the related researchers to have a better understanding of this field. Keywords:  Molecular Dynamics Simulation; Polymer Composites; Tribological Properties Introduction Polymer composites are widely applied in various aspects of scientific and engineering applications, such as industrial production, petrochemicals, automotive industry, mi

Effect of the Polyethyleneimine Coating on the Bending Properties of the Natural Fiber-Reinforced Biocomposites

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   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract In the scope of this study woven flax fibers are coated with aqueous polyethyleneimine (PEI) solution, in order to improve the bending properties of the produced flax fiber-reinforced epoxy composite. The textiles are coated with the different concentrations of PEI solution and integrated into the biobased epoxy using hand impregnation with subsequent hot-press. The results show that 1 wt% and 5 wt% PEI can considerably improve the bending properties of the tested biocomposites. Keywords:  Natural Fibers; Polyethyleneimine; Biocomposites; Surface Treatments Introduction Cellulose-based fiber composites have already approved their beneficial performance in the fields of automotive (interior) and sport and leisure [1,2]. Compared with synthetic fiber-reinforced composites, biocomposites containing cellulose-based natural fibers as a reinforcement offer numerous material specific advantages, like e.g. low density and go