Search

Blends of polylactic acid (PLA) and nanohydroxyapatite (NHA) were prepared through melt‐mixing by varying the composition of NHA from 1 to 5 wt%. The tensile properties of the PLA‐1 wt% NHA nanocomposite exhibited higher values than neat PLA. Beyond 1 wt% NHA, a drop in tensile properties of the PLA–NHA nanocomposites was observed due to agglomeration and poor interfacial adhesion between NHA and PLA. Therefore, NHA was surface modified (mNHA) using three different surface modifiers namely, 3‐aminopropyl triethoxysilane (APTES), sodium n‐dodecyl sulfate (SDS) and polyethylenimine (PEI). The surface treatment of NHA was studied through Fourier transform infrared spectroscopy (FTIR) and energy dispersive X‐ray (EDX). Results revealed that the tensile properties increased in order of PLA‐5 wt% mNHA (APTES) followed by PLA‐5 wt% mNHA (SDS), whereas PEI modified NHA resulted in lower tensile properties. Further, increasing mNHA loading to 30 wt%, decreased the tensile strength due to agglomeration of mNHA. POLYM. COMPOS., 39:2880–2888, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The effect of bisphenol A diglycidyl ether (BADGE) and electron beam (EB) irradiation on the properties of waste tire dust (WTD) -filled ethylene vinyl acetate (EVA) has been studied. The EVA/WTD ratio was fixed to 80:20, whereas the BADGE concentration varied from 1 to 5 wt%. The samples were then irradiated using a 3.0-MeV EB machine at 50 kGy to 200 kGy at increments of 50 kGy. All the samples were subjected to various mechanical, physical, and thermal tests. Prior to irradiation, the mechanical properties of the composites show a gradual decrease with increasing BADGE concentration. Such observation is attributed to the plasticizing effect of the BADGE, as indicated by the reduction in mixing torque and a 14% increase in the elongation at break with the addition of 5 wt% BADGE. Results of gel fraction indicated that BADGE did not accelerate the irradiation-induced crosslinking of EVA/WTD composites. The scanning electron micrographs and tan δ curves of EVA/WTD composites showed evidence that the addition of BADGE and EB irradiation of the EVA/WTD improves the compatibility of the composite. The overall results revealed that the irradiated EVA/WTD composite without BADGE gives a better enhancement in mechanical properties compared with the composites incorporated with the BADGE. J. VINYL ADDIT. TECHNOL., 23:172-180, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

This work focuses on the optimization and identification of blend with balanced mechanical properties of Co-PP/EPDM. The blending factors include time, temperature, screw speed, and blend ratio. Tensile strength and elongation at break were studied as the two responses. D-Optimal model was used to fit the regression line, which was validated using analysis of variance and “lack of fit” test. An average error of 10% (for tensile strength) and 3.2% (for elongation at break) was observed between the actual and predicted values. Further, the thermal stability, dynamic mechanical analysis, and phase morphology of the optimized blend were also investigated. [ABSTRACT FROM AUTHOR]

Herein, we report a facile process for the preparation of styrene and methyl-methacrylate copolymer nanocomposites containing reduced graphene oxide and silver nanoparticles ((R-(GO-(PS-PMMA))/AgNPs)) by using (i) microwave irradiation (MWI) to obtain R-(GO-(PS-PMMA))/AgNPs and (ii) the in situ bulk polymerization technique to produce RGO/AgNPs-(PS-PMMA). Various characterization techniques, including FT-IR, XPS, Raman spectroscopy, XRD, SEM, HR-TEM, DSC, and TGA analysis, were used to characterize the prepared nanocomposites. The Berkovich nanoindentation method was employed to determine the hardness and elastic modulus of the nanocomposites. The results showed that the MWI-produced nanocomposites were found to have enhanced morphological, structural, and thermal properties compared with those of the nanocomposites prepared by the in situ method. In addition, the antibacterial activity of the prepared nanocomposites against the E. coli HB 101 K-12 was investigated, whereby an inhibition zone of 3 mm (RGO/AgNPs-(PS-PMMA) and 27 mm (R-(GO-(PS-PMMA))/AgNPs) was achieved. This indicates that the MWI-prepared nanocomposite has stronger antibacterial activity than the in situ-prepared nanocomposite.