Xing Zhou^*

Journal of Renewable Materials, Vol.10, No.6, pp. 1623-1639, 2022, DOI:10.32604/jrm.2022.018935 - 20 January 2022

Abstract A facile method, focusing on emulsification, chain extension and dispersion process in preparing waterborne polyurethane, was developed to prepare emulsion with rod-like nanoparticles. The facile method involves a water addition procedure by in situ generated water to react with polyurethane prepolymer instead of the external water addition process. As a comparison, waterborne polyurethane was synthesized through the external water addition process. According to the characterization methods including FTIR, ¹H-NMR, TEM and water swelling experiments, it is suggested there are two kinds of hydrogen bonds interactions in hard/soft domain of the novel polyurethane, and the phase separation of More > Graphic Abstract

Yuhao Jiang, Jialan Yao, Chengfei Zhu^*

Journal of Renewable Materials, Vol.10, No.1, pp. 135-148, 2022, DOI:10.32604/jrm.2021.016304 - 27 July 2021

Abstract Poly(urea-formaldehyde) (PUF) microcapsules were prepared by in-situ polymerization with four different processes in this paper. The chemical composition, surface morphology, particle size distribution, and thermal stability were characterized by FTIR, SEM, particle size analyzer, and TGA, respectively. The results demonstrated that the agglomeration of the PUF microcapsules was related to the agglomeration of the emulsion particles caused by the changes of emulsion interface during the shell polymerization. Due to the slow deposition of the shell material, the PUF microcapsules with the core-shell structure prepared by the process with ammonium chloride as the last additive showed More > Graphic Abstract

Qiaoxin Zhang^1,2, Rui Chen¹, Ding Jin², Chen Zhou^2,*, Xuewu Li^3,4,5,*

Journal of Renewable Materials, Vol.9, No.1, pp. 129-144, 2021, DOI:10.32604/jrm.2021.011596 - 30 November 2020

Abstract In this paper, the microstructures and rolling contact fatigue behaviors of laser cladding Inconel 625 coatings with or without post-heat treatments were analyzed. The results revealed that the fatigue resistance of the laser cladding coating after any post-heat treatment was worse than that of the as-deposited coating. First, through the finite element analysis, the distribution of stress along the thickness direction of the coating was obtained, and it was concluded that the bonding interface between the coating and the matrix had little effect on the fatigue properties of the coating. Then X-ray diffraction (XRD), scanning… More >

Kamlendra Vikram¹, Uvaraja Ragavendran², Kanak Kalita^1,*, Ranjan Kumar Ghadai³, Xiao-Zhi Gao⁴

CMC-Computers, Materials & Continua, Vol.66, No.2, pp. 1771-1784, 2021, DOI:10.32604/cmc.2020.013946 - 26 November 2020

Abstract In this work, diamond-like carbon (DLC) thin film coatings are deposited on silicon substrates by using plasma-enhanced chemical vapour deposition (PECVD) technique. By varying the hydrogen (H₂) flow rate, CH₄−Argon (Ar) flow rate and deposition temperature (T_d) as per a Box-Behnken experimental design (BBD), 15 DLC deposition experiments are carried out. The Young’s modulus (E) and the coefficient of friction (COF) for the DLCs are measured. By using a second-order polynomial regression approach, two metamodels are built for E and COF, that establish them as functions of H₂ flow rate, CH₄-Ar flow rate and T_d. A non-dominated sorting More >

Verónica L. Mucci¹, M. E. Victoria Hormaiztegui², Mirta I. Aranguren^1,*

Journal of Renewable Materials, Vol.8, No.6, pp. 579-601, 2020, DOI:10.32604/jrm.2020.09455 - 12 May 2020

Abstract The increasing pressure from consumers and policy makers to reduce the use of synthetic polymers, whose production contributes to the depletion of non-renewable resources and are usually non- biodegradable, has prompted the efforts to find suitable bio-based sources for the production of polymers. Vegetable oils have been a frequently spotted in this search because they are versatile, highly available and a low cost liquid biosource, which can be used in the synthesis of a wide plethora of different polymers and reactive monomers. Following the same idea of reducing the environmental stress, the traditional polyurethanes that… More >

Ingrid Souza Vieira da Silva¹, Natália Soares Prado¹, Patrícia Gontijo de Melo², Danilo Campion Arantes³, Mara Zeni Andrade⁴, Harumi Otaguro¹, Daniel Pasquini^1,*

Journal of Renewable Materials, Vol.7, No.1, pp. 73-87, 2019, DOI:10.32604/jrm.2019.00042

Abstract In this work, nine different types of edible coating based on pectin, cellulose nanocrystals, glycerol, and essential oil of lemongrass were prepared and used to coat strawberries with a film formed directly on the surface of the coated fruit. The effects of the different edible coatings on refrigerated fruits in terms of weight loss, titratable acidity, total soluble solids, pH, and anthocyanin content was evaluated after 2 days, 4 days, 6 days, and 8 days of storage. Application of the edible coatings reduced the weight loss of the coated strawberries and the anthocyanin content. The More >

Azam Sardari^1,2, Ali Asghar Sabbagh Alvani^1,2,3,*, Seyed Reza Ghaffarian^1,2

Journal of Renewable Materials, Vol.7, No.1, pp. 31-40, 2019, DOI:10.32604/jrm.2019.00045

Abstract In this study, three sorts of polyols were successfully synthesized from castor oil using a Dean-Stark quick, eco-friendly and high-efficiency method. For this purpose, castor oil was epoxidized in the presence of two types of catalysts including γ-alumina and formic acid, named as ECOAl and ECOF, respectively. Epoxidized castor oils were then characterized by use of hydrogen nuclear magnetic resonance (H-NMR) and oxirane oxygen content analysis. The relative percentages of conversion double bond to oxirane were obtained 96% and 74% for ECOAl and ECOF, respectively. Ring opening reaction of ECOAl was performed by two types More >

A. Abolins*, V. Yakushin and D. Vilsone

Journal of Renewable Materials, Vol.6, No.7, pp. 737-745, 2018, DOI:10.32604/JRM.2018.00119

Abstract Linseed oil was epoxidized using hydrogen peroxide (H2O2), acetic acid (AcOH) and ion exchange resin Amberlite IR-120 as a catalyst. Epoxidized oil was separately dissolved in isopropyl alcohol (IPA) or diethylene glycol butyl ether (DGBE) and phosphorylated with different amounts of phosphoric (H3PO4) acid (1%, 2%, 3% and 5%). The formation of phosphate polyesters was confirmed by Fourier-transform infrared (FTIR) and 31P nuclear magnetic resonance (NMR) spectra. Based on the synthesized polyols, polyurethane (PU) coatings were prepared. PU coating based on linseed oil diethylene glycol ester polyol was used as the reference. For the characterization More >

Kunal Wazarkar, Anagha Sabnis*

Journal of Renewable Materials, Vol.6, No.5, pp. 517-528, 2018, DOI:10.7569/JRM.2017.634181

Abstract This research work discloses the preparation of polyurethane coatings from cardanol modified using thiolene chemistry, wherein unsaturated long alkyl chain of cardanol was successfully utilized via thiol-ene click reaction to synthesize polyol. For this purpose, cardanol and thioglycerol was reacted in the presence of Irgacure 184 (photoinitiator) and 1,8-Diazabicyclo[5.4.0]undec-7-ene (catalyst) and exposed to UV light for 12 h at 80 °C. One mole of thioglycerol was successfully added across the double bond of fatty chain of cardanol and confirmed by chemical and spectroscopic analysis. Further, the polyol thus prepared was cured with various polyisocyanates, viz., More >

Dinesh Balgude, Anagha Sabnis^*

Journal of Renewable Materials, Vol.2, No.3, pp. 235-245, 2014, DOI:10.7569/JRM.2014.634115

Abstract Renewable resource-based hybrid crosslinker was successfully synthesized via sol-gel technology. The synthesis involved malenization of Cashew Nut Shell Liquid (CNSL) followed by its silane modifi cation and subsequent hydrolysis and condensation with tetraethyl orthosilicate (TEOS). The synthesized crosslinker was characterized by spectroscopic analysis (FT-IR, ¹ H-NMR, ¹³C-NMR and ²⁹Si-NMR) for structural elucidation. The crosslinker was further formulated in a conventional stoving system. Fully-cured coatings were obtained after stoving at 120°C for ½ hr and were then evaluated for physical, mechanical, chemical, optical, accelerated weathering, electrochemical and morphological properties. The incorporation of hybrid crosslinker in a conventional stoving More >