Hongxiang Liu^1,2,,*, Neng Xiong^1,2, Songli Wang^1,2, Wei Zhang^1,2, Bo Yong^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.3, pp. 549-561, 2022, DOI:10.32604/fdmp.2022.017979 - 22 February 2022

Abstract

The effects of a magnesium-based layered composite on the flammability of a phenolic epoxy resin (EP) are studied. In order to produce the required composite material, first, magnesium hydroxide, aluminum salt and deionized water are mixed into a reactor according to a certain proportion to induce a hydrothermal reaction; then, the feed liquid is filtered out using a solid-liquid separation procedure; finally, the material is dried and crushed. In order to evaluate its effects on the flammability of the EP, first, m-phenylenediamine is added to EP and vacuum defoamation is performed; then, EP is poured into

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Li Wang^1,2,#, Rongbai Tong^3,#, Juanli Wang^1,2,*, Jintao Wan^1,2,*, Yuhu Li^1,2, Pujun Jin^1,2, Daodao Hu^1,2

Journal of Renewable Materials, Vol.10, No.5, pp. 1349-1364, 2022, DOI:10.32604/jrm.2022.019372 - 22 December 2021

Abstract Quest for bio-based halogen-free green flame retardant has attracted many concerns in recent years. Herein a reactive functional flame retardant containing phosphorus VDP is synthesized from vanillin, 9,10-dihydro-9-oxa-10-phosphophene-10-oxide (DOPO) and phenol via a facile way. VDP is characterized with ¹H NMR, ³¹P NMR, FTIR and Time of Flight Mass Spectrometry, and used as a new reactive flame retardant for bisphenol epoxy thermosets. Thermogravimetry analysis shows that when the VDP loading is only 0.5P% (based on phosphorus content), the residue increases from 14.2% to 21.1% at 750°C in N₂ compare with neat DGEBA. Correspondingly, the limit oxygen index… More >

JALPA V. CHOPDA, DHARMESH B. SANKHAVARA, JIGNESH P. PATEL, P. H. PARSANIA^*

Journal of Polymer Materials, Vol.38, No.1-2, pp. 35-48, 2021, DOI:10.32381/JPM.2021.38.1-2.4

Abstract Conventional curing study of epoxy resin of (2E, 6E)-bis (4-hydroxybenzylidene)-4-methyl cyclohexanone (EMBHBC) was conducted at 140 0 /150 0 C by using 4,4’-diaminodiphenylmethane (DDM),4,4’-diaminodiphenylsulphone (DDS),4-4’-diaminodiphenyl ether (DDE), p-phenylenediamine (PDA), 1,2,3,6-tetrahydrophthalic anhydride(THPA), maleic anhydride (MAH) and pyromellitic dianhydride (PMDA). The gel time for DDS, THPA and DDM hardeners are found considerably longer than those of DDE, PDA, MAH and PMDA systems indicated different reactivity towards curing of EMBHBC. Sol–gel analysis of cured resins was carried out in DMF at room temperature. Diamines cured samples showed 76.3-97.5% gel fractions, while anhydrides cured samples showed 84.6-99.6% gel fractions.… More >

DHARMESH B. SANKHAVARA, JALPA V. CHOPDA, JIGNESH P. PATEL, PARSOTAM H. PARSANIA^*

Journal of Polymer Materials, Vol.38, No.1-2, pp. 11-19, 2021, DOI:10.32381/JPM.2021.38.1-2.2

Abstract The curing of epoxy resin of (2E, 6E)-2,6-bis(4-hydroxy benzylidene) cyclohexanone (EBHBC) was carried out at four different heating rates in the nitrogen atmosphere by using 4,4’-diamino diphenylmethane (DDM), 4,4’-diamino diphenyl sulfone (DDS), and 1,2,3,6-tetrahydrophthalic anhydride (THPA) as hardeners. From DSC curves onset, peak exotherm and end set temperatures, as well as heat release, were derived. The energy of activation was derived following Kissinger and Ozawa methods. Observed trend in Ea is EBHBC-THPA > EBHBCDDS > EBHBC-DDM > EBHBC. Nature and chemical structure of the hardeners affected the curing of EBHBC. More >

Syed Waheedullah Ghori^1,*, G. Srinivasa Rao²

Journal of Renewable Materials, Vol.9, No.7, pp. 1283-1292, 2021, DOI:10.32604/jrm.2021.014987 - 18 March 2021

Abstract Date palm fiber (DPF) and kenaf fiber were reinforced in epoxy having various fiber loading 40%, 50%, and 60% by weight. These hybrid samples were manufactured by hot press technique and then characterized for tensile, impact, and morphological behavior to evaluate the ratio of fibers in the hybrid composites; the addition of kenaf improved the tensile properties, Scanning Electron Microscopy (SEM) revealed the interfacial bonding of fiber/matrix, and dispersion and void content in composites. Impact test studies reflected the effect of natural fiber with epoxy, level of stress transfer from matrix to reinforced material, and More > Graphic Abstract

ANIL KUMAR VEERAPANENI¹, CHANDRASEKAR KUPPAN^2,*, MURTHY CHAVALI^3,*

Journal of Polymer Materials, Vol.37, No.3-4, pp. 121-130, 2020, DOI:10.32381/JPM.2020.37.3-4.1

Abstract The mechanical properties of hybrid nanocomposites made of epoxy/glass fibre dispersed with nano-α-Al₂ O₃ powder at different weight percentages were studied.The effect of nano-α- Al₂O₃ size and wt% on mechanical properties like tensile, flexural, interlaminar shear stress and hardness enhanced because of their higher surface area and interfacial polymer-metal interaction. The nanoparticle embedded laminates have shown improvement in flexural strength,and hardness when compared to laminate without nano-α-Al₂ O₃. The properties varied with the loading and size of the nanoparticles. The tensile strength was highest for 0.5 wt% of 200nm nano-α-Al₂O₃, which is 167.80 N/m₂.The highest flexural strength was observed More >

Xiaofu Wang^1,*, Xiong Zhang¹, Yan He², Chunming Lian³

Journal of Renewable Materials, Vol.8, No.8, pp. 947-968, 2020, DOI:10.32604/jrm.2020.011327 - 10 July 2020

Abstract In order to solve the problem of urban surface runoff, it is necessary to study permeable brick deeply. Tensile test and DMA test were used to study the binder material of permeable brick, and a material with the best mechanical properties was selected as the binder of resin based permeable brick; The permeable brick with single gradation and continuous gradation and porosity of 0.1–0.5 gradient is constructed by 3D modeling method. The particle composition and the seepage simulation results of permeable brick under different design parameters were analyzed; A resin-based permeable brick with micro-pores was… More >

JIANGBO WANG^*

Journal of Polymer Materials, Vol.36, No.4, pp. 381-389, 2019, DOI:10.32381/JPM.2019.36.04.7

Abstract In this study, a novel flame retardant polyvinylphenylsilsesquioxane (PVP) was added into epoxy resin (EP) to prepare EP/PVP (FREP) composites. The results of cone calorimeter measurement showed that in comparison with virgin EP, the peak heat release rate (PHRR) and total heat release (THR) of FREP were reduced by 27.3% and 10.4%, respectively. Moreover, the thermal degradation behavior of FREP was studied by the Kissinger and Ozawa-Flynn-Wall methods. The results suggested that the addition of PVP greatly enhanced the thermal stability of EP in the final stage, which could be attributed to that the branched More >

JALPA V. CHOPDA, DHARMESH B. SANKHAVARA, JIGNESH P. PATEL, P. H. PARSANIA^*

Journal of Polymer Materials, Vol.36, No.1, pp. 101-109, 2019, DOI:10.32381/JPM.2019.36.01.8

Abstract The epoxy resin (EMBHBC) of (2E,6E)-bis (4-hydroxybenzylidene)-4-methyl cyclohexanone (MBHBC) was synthesized by condensing 0.5 mol MBHBC and 2.5 mol epichlorohydrin in 500 mL isopropyl alcohol as a solvent and 1.0 mol NaOH in 50 mL water as a catalyst at 80°C for 3 h. The structure of EMBHBC was supported by UV-Vis, FTIR, ¹ HNMR and ¹³CNMR spectroscopic techniques. Molecular weights and molecular weight distribution of EMBHBC were determined by gel permeation chromatography. DSC thermogram of EMBHC showed one endothermic transition (95.9°C) and two exothermic transitions (317.7°C and 382.2°C) due to melting and decomposition transitions, respectively. More >

DHARMESH B. SANKHAVARA, JALPA CHOPDA, JIGNESH P. PATEL, P. H. PARSANIA^*

Journal of Polymer Materials, Vol.36, No.1, pp. 13-21, 2019, DOI:10.32381/JPM.2019.36.01.2

Abstract Chalcone based epoxy resin (EBHBC) of (2E, 6E)- bis(4-hydroxybenzylidene) cyclohexanone (BHBC) was synthesized by condensing 0.5 mol BHBC and 2.5 mol epichlorohydrin in 500 mL isopropanol as a solvent and 1.0 mol NaOH in 50 mL water as a catalyst at 80o C. The structure of EBHBC is supported by spectral techniques. Molecular weights and molecular weight distribution of EBHBC were determined by gel permeation chromatography. DSC thermogram of EBHC showed one endothermic transition (146.1°C) and two endothermic transitions (253.52°C and 397.34°C) due to melting, some physical change and decomposition transitions, respectively. EBHBC is thermally More >