Considering the importance of urea-formaldehyde (UF) resins in the wood industry, this work reports on a new bio-based modification of UF resins. The use of 5-hydroxymethyl furfural (HMF) is motivated by the current concerns about the effects of formaldehyde on human health. UF and urea-HMF-formaldehyde (UHF) resins were synthesized by an alkaline-acid method and characterized by FTIR, thermogravimetric analysis, and differential scanning calorimetry. The UHF, as a newly modified polymeric resin, was thermally characterized, and it was found that its thermo-stability and char yield was improved. In order to investigate the performance of the UHF, the preparation of particleboards with the UHF as adhesive, as well as its film formation ability have been studied. The UHF films formed on wood panels were uniform without any crack. Film formation ability of the UHF resin was improved due to the presence of more hydroxyl groups as well as furan rings of the HMF moieties resulting in more activated groups to be bonded by wood. Furthermore, formaldehyde release of the particleboards bonded by UHF was significantly lower than that of which bonded by the UF resin. Lab particleboards using the UHF resins showed higher modulus of rupture, modulus of elasticity, and internal bond compared to boards with UF resins, as well as lower water absorption and thickness swelling. Based on these results UHF resin can be considered as a possible candidate as adhesive for wood and wood based panels.

A facile solvent-less approach to toughen epoxy thermosets by means of a bio-based resin, that is, poly(furfuryl alcohol) (PFA; furan resin) is reported. The bio-resin PFA was firstly synthesized through polycondensation reaction of furfuryl alcohol as a bio-monomer and maleic anhydride as a catalyst. Different amounts of PFA were blended with diglycidyl ether of bisphenol A epoxy resin and cured by diethylenetriamine as a hardener, which simultaneously cross-linked both of the epoxy and PFA resins. The curing process was studied by Furrier transform infrared spectroscopy and differential scanning calorimetry. Scanning electron microscopy of the chemically cured blends revealed no phase separation. It was found remarkable increase in flexural modulus and strength of the neat and modified epoxies with increasing PFA content up to around 15%. Moreover, in comparison with neat epoxy, the epoxy-PFA thermosets showed 60% increase in critical stress intensity factor and 123% increase in critical strain energy release rate. In fact, chemical reaction of PFA-incorporated epoxy could toughen the epoxy matrix without sacrificing the flexural strength and modulus. Toughening was obtained through cross-link density reduction. As exhibited by dynamic mechanical thermal analysis, Tan δ and magnitude of β-relaxation were also increased for the epoxy-PFA alloys. Overall, this green, simple, concise and cost-effective approach was suggested for being considered to produce toughened epoxy thermosets in industrial scale.

Furfuryl alcohol as a biomass-derived monomer was used for synthesizing poly(furfuryl alcohol). A diglycidyl ether of bisphenol A (DGEBA) epoxy resin along with 3% and 15% by weight of the poly(furfuryl alcohol) was cured using an aliphatic amine hardener. The cure kinetics of the DGEBA/poly(furfuryl alcohol)/amine systems were investigated by nonisothermal differential scanning calorimetry. The kinetic triplets [E a , A a , and f(a)] were computed by using an integral isoconversional method. Based on the E a -dependency results a single-step autocatalytic model was suggested for the reactions mechanism, however, the A a -dependency and f(a) analysis did not confirm the suggested model. Detailed kinetics analysis revealed that the cure reaction mechanism of the DGEBA did not change due to the presence of the poly(furfuryl alcohol) in the degree of conversion range < 0.75, nevertheless, it dramatically changed in the degree of conversion range > 0.75 due to the presence of 15 wt % poly(furfuryl alcohol). V C 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45432.

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This study focuses on the utilization of ZnO (as synthetic) and mango peel (natural adsorbent) to remove blue 221 dye from aqueous solutions. First, ZnO nanoparticles (NPs) were synthesized and detected using the descriptorbased techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), N2 adsorption/desorption isotherms (BET), and X-ray diffraction (XRD). Various operational parameters including adsorbent concentration, pH, adsorbent dose, contact time, and stirring speed were investigated. The obtained kinetic results demonstrated great compatibility of the pseudo-second-order model with the experimental data. The effects of thermodynamic parameters were calculated to confirm the endothermic, spontaneous and physical nature of adsorption process. Langmuir and Freundlich isotherm models were utilized to fit the obtained equilibrium data. Freundlich model was found sufficient to explain the adsorption of blue 221 dye by ZnO NPs and mango peel. The results indicated that the ZnO NPs performed better in blue 221 dye removal as compared with mango peel. The mean size of ZnO NPs was found to be 22.16 nm. The specific surface area of ZnO NPs was obtained 26.85 m 2 .g -1 and pore volume and pore-size were 0.0581 cm 3 .g -1 and 1.22 nm, respectively. The maximum adsorption capacity of blue 221 dye on ZnO NPs and mango peel was estimated as 133.33 and 476.19 mg.g -1 , respectively.

To find a chemical sensor for detection of Cyclosarin (GF) nerve agent, we studied its interaction with B 24 N 24 , AlB 23 N 24 , B 16 N 16 and AlB 15 N 16 nanoclusters by means of density functional theory calculations. All calculations were investigated whit the M06 method and 6-311G(d,p) basis set. It was demonstrated that the interaction of GF with AlB 23 N 24 and AlB 15 N 16 is more stable than that of the B 24 N 24 and B 16 N 16. Thermodynamic parameters indicated that the AlB 23 N 24 and AlB 15 N 16 interactions with the GF are exothermic and spontaneous. Despite both AlB 23 N 24 and AlB 15 N 16 demonstrated strong adsorption, the electronic properties calculation indicated that AlB 15 N 16 sensitive to the nerve agent adsorption. Our results predicted AlB 15 N 16 has good potential as a sensor for the detection of GF.