Search

Recycled polymeric materials recovered from E‐waste, have gained importance in the recent years, due to the value addition of properties in the recycled materials. In the current work, a polymeric blends formulated from keyboard waste plastics was value added using a flame retardant (FR), and these plastics are not incorporated with FR during its processing. This work was carried out to enhance the FR property of polymers recovered from keyboard waste, and to study the effects of these additives on the mechanical properties of the polymeric blends. The FR tri phenyl phosphate (TPP), and a hybrid FR combining TPP with sepiolite, was added in different proportions to the blend. The FR blends were analyzed with UL‐94 and LOI and it was observed that the blends with hybrid FR showed higher FR properties, as the results of UL‐94 and LOI showed V‐1 and 29%, respectively. The cone calorimetry results showed that the peak heat release rate of the blends was improved from 704 to 533 KJ/m2. The gas and condensed phase reaction has been explained with an illustration. FTIR and TGA with and without the FR were performed. The mechanical properties of the blends drastically reduced after the addition of FRs, hence an impact modifier was added in order to regain the lost mechanical properties, and a morphological analysis was carried out to compare the influence of impact modifier in the polymeric blend. [ABSTRACT FROM AUTHOR]

A trifunctional epoxy resin from itaconic acid (TEIA) was synthesized from a renewable resource-based itaconic acid by allylation of itaconic acid to form diallyl itaconate by using m-chloroperoxybenzoic acid as oxidizing agents followed by epoxidation of allylic C═C bond of diallyl itaconate methylhexahydropthalic anhydride as curing agent in the presence of 2-methyl imidazole as a catalyst. The chemical structure of the synthesized resins was confirmed by Fourier transform infrared and nuclear magnetic resonance (1H-NMR and 13C-NMR) spectroscopy analysis. The mechanical, thermal, and rheological performances of the TEIA were also investigated and compared with diglycidyl ether of bisphenol A and a plant-based epoxidized soybean oil bioresin cured with the same curing agent. The higher epoxy value of 1.02, lower viscosity (0.96 Pa s at 25°C), higher mechanical, and higher curing reactivity toward methylhexahydropthalic anhydride of TEIA as compared with epoxidized soybean oil and comparable with diglycidyl ether of bisphenol A demonstrated significant evidence to design and develop a novel bio-based epoxy resin with high performance to substitute the petroleum-based epoxy resin. [ABSTRACT FROM AUTHOR]

Catastrophic breakdown that occurs during the flight of supersonic vehicles demands more focused research in the insulation of rocket engines. At present, optimization of polymeric ablatives as viable insulation for solid rocket motor casing has a prominent role in the successful mission of rockets. Among polymers, elastomer serves an imperative part. Comprehensive investigations were disclosed, especially in the elastomeric heat shielding materials with various reinforcing agents. In this paper, research progress of mostly used elastomers is reviewed, and a circumstantial understanding about the features of ablation and insulation has been validated. [ABSTRACT FROM AUTHOR]

The main aim of this study was to synthesis of poly (lactic acid) (PLA)-graft-glycidyl methacrylate (GMA) as well as its influence on the properties of PLA/banana fiber biocomposites. PLA-graft-GMA graft copolymer (GC) was synthesized by melt blending PLA with GMA using benzoyl peroxide and dicumyl peroxide as initiators. Graft copolymerization was confirmed by FTIR and 1H-NMR spectroscopic studies. PLA/silane treated banana fiber (SiB) biocomposites with various GC concentrations were prepared by melt blending followed by injection molding techniques. The influence of GC content on the mechanical, thermal and moisture resistance properties of the composite was investigated. The addition of 15 wt% GC content in the biocomposite provided optimum tensile and flexural strength, which is attributed to the greater compatibility between fiber and PLA matrix. The thermal properties of biocomposites have been evaluated using thermogravimetric analysis which provided evidence of improved interfacial adhesion between SiB and PLA by the addition of GC. Additionally, GC enhanced the moisture absorption resistance of biocomposites. These results indicated that GC is indeed a good candidate as a compatibilizing agent to improve the compatibility in PLA/fiber biocomposites. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]