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The use of residues from human activities has been currently gaining ground in the national and international markets, aiming toward the production of more sustainable materials that are less aggressive to the environment. Reusing and adding value to new products has also become an important factor in reducing production costs and the best alternative for this is process optimization. The choice for residual balsa wood was due to its rapid growth and low density, as well as for its ease of engineering and determining the ideal amount of resin for different types of panels. This study aims to investigate the influence of the content variation of castor oil-based polyurethane resin on the physical and mechanical properties of OSB board particles made from residual balsa wood in reforestation areas. The panels were produced with 8, 10, and 12 % commercial castor oil-based polyurethane resin and 9 mm long particles; their physical and mechanical characterizations followed international normative recommendations. The results indicated that the panels with resin contents higher than 10 % reached the minimum regulatory requirements for type 2 OSB panels, suitable for structural application. On the other hand, the panels produced with 8 % resin reached the minimum requirements for type 1 OSB panels, suitable for non-structural use by the furniture industry, such as linings and partitions. Therefore, our study concludes that the variation of resin contents for OSB panels of residual balsa wood allowed us to achieve optimal levels for the use of castor oil-based polyurethane resin, reaching minimum values recommended by regulations for OSB panels type 1 and 2 and a great possibility of application of this product for engineered materials. [ABSTRACT FROM AUTHOR]

The use of residues from human activities has been currently gaining ground in the national and international markets, aiming toward the production of more sustainable materials that are less aggressive to the environment. Reusing and adding value to new products has also become an important factor in reducing production costs and the best alternative for this is process optimization. The choice for residual balsa wood was due to its rapid growth and low density, as well as for its ease of engineering and determining the ideal amount of resin for different types of panels. This study aims to investigate the influence of the content variation of castor oil-based polyurethane resin on the physical and mechanical properties of OSB board particles made from residual balsa wood in reforestation areas. The panels were produced with 8, 10, and 12 % commercial castor oil-based polyurethane resin and 9 mm long particles; their physical and mechanical characterizations followed international normative recommendations. The results indicated that the panels with resin contents higher than 10 % reached the minimum regulatory requirements for type 2 OSB panels, suitable for structural application. On the other hand, the panels produced with 8 % resin reached the minimum requirements for type 1 OSB panels, suitable for non-structural use by the furniture industry, such as linings and partitions. Therefore, our study concludes that the variation of resin contents for OSB panels of residual balsa wood allowed us to achieve optimal levels for the use of castor oil-based polyurethane resin, reaching minimum values recommended by regulations for OSB panels type 1 and 2 and a great possibility of application of this product for engineered materials.

This study investigated the effect of organic resin contained in glass wool on synthesis of alkali-activated binders. The study was performed on glass wool containing sugar or phenolic resin, comparing it with glass wool that did not contain resin, as a reference. The results showed that the organic resin could be qualitatively identified using Fourier-transform infrared spectroscopy (FTIR) and thermo gravimetry-mass spectrometer (TG-MS), with gradual decomposition occurring between 200 °C and 550 °C. The presence of organic resin reduced the milling efficiency of glass wool, modified the rheology by increasing the liquid demand, and slowed the strength development at room temperature. However, interestingly, the effect of the resin on the strength of the paste was less obvious at an age of 28 days. Curing for 24 h at 40 °C was beneficial for one-day strength development, in comparison to 20 °C and 60 °C, independent of the presence of the resin. All the cured paste samples, with and without resin, achieved a compressive strength of more than 40 MPa at 28 days, satisfying the requirement for many structural applications. Nevertheless, water immersion affected the materials’ strength, suggesting their suitability for dry environments or the need for suitable co-binders to increase their durability and water resistance.

Resorcinol 1,4-phthalaldehyde resin (RPR) was successfully synthesized using a solvent-free self-assembly method employing a template (F127) and a mixture of resorcinol and 14-phthalaldehyde. After the removal of the template (F127) by heating, the PRR exhibited an ordered mesoporous structure with a size of approximately 5.8 nm. After impregnating with Pd species, a RPR supported Pd catalyst (Pd/RPR) was finally obtained, which demonstrated outstanding catalytic performance and good stability in the hydrodeoxygenation of vanillin. With an optimal catalyst, 100% conversion of vanillin and 96.7% selectivity for 2-methoxy-4-methylphenol were achieved under the reaction conditions of 2 MPa H 2 in ethanol at 90 ℃ over 4 hours. The superior catalytic properties of Pd/RPR with high activity and stability are anticipated to be significant for future biofuel upgrades. [Display omitted] • A synthetic method of resorcinol 1,4-phthalaldehyde resin (RPR) and its utilization as a support for palladium nanoparticles are reported. • Pd/RPR catalyst shows a superior activity and a high stability in the hydrodeoxygenation (HDO) of vanillin. • The effects of various reaction conditions in the HDO process are also investigated. [ABSTRACT FROM AUTHOR]

This work presents a study for using Balsa wood (Ochroma pyramidale) waste in the production of oriented strand boards (OSB) agglomerated with castor oil polyurethane resin. For this study, were produced OSB panels with different densities (300 kg/m3 and 400 kg/m3), with 10 mm thickness and castor oil polyurethane resin in different contents (11% and 15%). The Balsa wood particles were characterized by physical, chemical and anatomical tests that identified the potential of this by-product as raw material for the production of OSB panels. Subsequently, the thermo-physical-mechanical properties of low density OSB panels produced with Balsa wood waste were determined. The results indicated that panels with a density of 400 kg/m3 and a resin content of 15% obtained a performance that classifies them as OSB type 1—internal and non-structural use panels according to the European Standard EN 300: 2002—OSB—definitions, classification and specifications. [ABSTRACT FROM AUTHOR]

Adsorption behaviors of Se(IV) and Te(IV) on the inorganic ion exchanger ceric tungstate (CeW) was studied under static and dynamic conditions and compared with the adsorption on the organic cation and anion exchangers Dowex-50X8 and AG-2X8, respectively. The radioactive isotopes 75Se and 123mTe were used to trace the respective elements. Some parameters affecting the adsorption were investigated under static conditions. In the case of batch technique the adsorption was studied from slightly acidic HCl as well as slightly alkaline media, i. e. at two pH-ranges. Se(IV) and Te(IV) were adsorbed on both the inorganic ion exchanger (CeW) and on AG-2X8, from slightly alkaline solutions. From the similarity of adsorption on both ion exchangers it was clear that (CeW) acts as an anion exchanger. Moreover, the obtained Kd-values for the adsorption on (CeW) were much higher than those for the adsorption on the organic anion exchanger AG-2X8. Se(IV) was not adsorbed on Dowex-50X8 all over the studied pH-range whereas Te(IV) was slightly adsorbed. Loading and elution behaviors of Se(IV) and Te(IV) on columns of AG-2X8 and (CeW) were studied using solutions of HCl of different concentrations. Some good separation alternatives of Se(IV) and Te(IV) under certain conditions were achieved. [ABSTRACT FROM AUTHOR]

Poly(acrylic acid-dimethylaminoethyl methacrylate) was prepared by γ-radiation-induced copolymerization at a radiation dose of 60 kGy and a dose rate of 1.25 kGy h. The resin obtained was used to remove U(VI) from simulated solution of the waste from the Fuel Manufacturing Pilot Plant (FMPP). A preliminary test of U(VI) adsorption onto the resin showed high affinity of this resin for U(VI) ions. The adsorption behavior toward the U(VI) ions was studied in relation to the contact time, pH, temperature, resin dosage, and initial concentration of metal ions. The adsorption isotherms of uranium onto the resin were described using the Langmuir and Freundlich models, with the Langmuir model being more adequate to the experimental equilibrium data. Without foreign ions, the maximum adsorption capacity of the resin for U(VI) was 105.7 mg g. X-ray fluorescence was used to evaluate the amount of U(VI) ions on the resin sample before and after the adsorption. [ABSTRACT FROM AUTHOR]

The prepared organic resin based N-enriched porous carbon nanosheets possess ultrahigh specific surface area (3542 m2 g−1), and exhibit high energy density of 31.4 Wh kg−1 in the Agar/Na 2 SO 4 gel electrolyte based symmetric flexible capacitor. [Display omitted] • N-enriched carbon nanosheets (N-PCNs) are prepared by using organic resin as precursor and g-C 3 N 4 as template. • N-PCNs exhibit an ultrahigh specific surface area of 3542 m2 g−1 and hierarchical porous structure. • N-PCNs show a high energy density of 31.4 Wh kg−1 in the Agar/Na 2 SO 4 gel electrolyte based symmetric flexible capacitor. Organic resins are considered as a kind of promising precursors to prepare carbon materials due to its broad resource, high char yield. Nevertheless, it is still a chanllenge on preparing of electrode materials with large specific surface area, high content of heteroatom doping, and remarkable electrochemical properties from organic resins for supercapacitors. Here we report a efficient and facile synthetic strategy to fabricate ultrahigh specific surface area and N-enriched porous carbon nanosheets (N-PCNs) using g-C 3 N 4 as template, L-Tyrosine-based resin as carbon precursor by hydrothermal polymerization and following KOH activation process. The effects of activator ratio and activation temperature on the morphology, structure and capacitance performance of N-PCNs have been systematacially studied. The prepared N-enriched (4.13 at%) porous carbon nanosheets with ultrahigh specific surface area (3542 m2 g−1) show excellent capacitance performance. The optimized sample presents an excellent specific capacitance of 349 F g−1 at 0.5 A g−1, and can also maintain 218 F g−1 at 50 A g−1, showing an outstanding rate performance. Moreover, the symmetric flexible capacitor assembled by Agar/Na 2 SO 4 gel electrolyte displays a relatively high energy density of 31.4 Wh kg−1 at 225 W kg−1. [ABSTRACT FROM AUTHOR]

Highlights: [•] Use of multiple linear regression to model the silicone paint coating. [•] Evaluation of selected factors on selected properties of silicone paint coatings. [•] Use of statistical methods in silicone paint recipe technology. [Copyright &y& Elsevier]

A carboxylic gel-type resin, poly-4-vinylpyridine-methacrylic acid-N, N'-methylenebisacrylamide is designed and synthesized in order to be able to incorporate both FeIII and, potentially, also AuIII in its polymer framework. Along with the gradual substitution of H+ with Na+, of Na+ with Fe3+/3 and after a very controlled and gradual precipitation of FeIII as oxihydroxides induced by the hydrolysis of urea directly inside the nanoporous domains of the metalated resin particles, an organic-inorganic composite is obtained. The material is characterized with TGA, ESEM, XRMA and Mössbauer spectroscopy. [ABSTRACT FROM AUTHOR]

The sorption behaviour of phosphate on strong basic anion exchanger, Amberlite IRA-400 (SO42- form) is studied as a function of pH (3-11) at two different initial concentration ranges (0.161 - 0.807 mmol l-1, 3.874 - 6.134 mmol l-1) at 25 °C. The stiochiometry of the exchange reactions is observed to be dependent upon concentration and pH of the solutions. It is suggested that the sorption of phosphate takes place initially as PO43- followed by HPO42-/H2PO4-. The data obtained is explained with the help of a modified Langmuir and mass law action equations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The resin in glass wool waste could be gradually eliminated by thermal treatment from 200 to 550 °C. • The resin affected the milling efficiency, rheology, heat of reaction and strength development. • Curing at 40 °C was beneficial for strength development in comparison to 20 and 60 °C. • The 28-days compressive strength was less affected by the presence of the resin. • The incorporation of suitable co-binders would increase the materials' stability. This study investigated the effect of organic resin contained in glass wool on synthesis of alkali-activated binders. The study was performed on glass wool containing sugar or phenolic resin, comparing it with glass wool that did not contain resin, as a reference. The results showed that the organic resin could be qualitatively identified using Fourier-transform infrared spectroscopy (FTIR) and thermo gravimetry-mass spectrometer (TG-MS), with gradual decomposition occurring between 200 °C and 550 °C. The presence of organic resin reduced the milling efficiency of glass wool, modified the rheology by increasing the liquid demand, and slowed the strength development at room temperature. However, interestingly, the effect of the resin on the strength of the paste was less obvious at an age of 28 days. Curing for 24 h at 40 °C was beneficial for one-day strength development, in comparison to 20 °C and 60 °C, independent of the presence of the resin. All the cured paste samples, with and without resin, achieved a compressive strength of more than 40 MPa at 28 days, satisfying the requirement for many structural applications. Nevertheless, water immersion affected the materials' strength, suggesting their suitability for dry environments or the need for suitable co-binders to increase their durability and water resistance. [ABSTRACT FROM AUTHOR]