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  • Open Access

    ARTICLE

    GC-MS Analysis of Metabolites in Filling Grains of Rice-Tartary Buckwheat (Fagopyrum tataricum) in Comparison to Conventional Tartary Buckwheat

    Chenggang Liang1,#, Chunyu Wei1,#, Yan Wang1,*, Wujuan Yu1, Kai Liao1, Taoxiong Shi1, Dabing Xiang2,3, Qijiao Chen1

    Phyton-International Journal of Experimental Botany, Vol.90, No.3, pp. 871-893, 2021, DOI:10.32604/phyton.2021.014242

    Abstract Rice-Tartary buckwheat (RTB) is a special germplasm of Tartary buckwheat. In this study, the appraisal of taste quality between RTB and conventional Tartary buckwheat (CTB) was presented, and the metabolites in kernels at three typical grain filling stage (GFS) were investigated. Unlike CTB, RTB showed thin shell seeds without longitudinal furrows at maturity, which was easily artificially dehulled. Sense organ test indicated that RTB exhibited better taste quality because of the higher values of appearance, viscosity, taste and summary were appraised. In total, 92 metabolites were identified in kernels using GM-MS metabolomics platform. The levels of most metabolites changed greatly… More >

  • Open Access

    ARTICLE

    New Biobased Polyurethane Materials from Modified Vegetable Oil

    Chakib Mokhtari1, Fouad Malek1, Sami Halila2, Mohamed Naceur Belgacem3,*, Ramzi Khiari3,4,5,*

    Journal of Renewable Materials, Vol.9, No.7, pp. 1213-1223, 2021, DOI:10.32604/jrm.2021.015475

    Abstract Bio-based polyurethanes (PUs) have been occurred a large attention nowadays. It was found to be an alternative to the petrochemical based materials to the fact of their weak environmental influence, availability, good price and biodegradability. In addition, the nature shows several bio-derived compounds as raw materials for the synthesis of polyols, including the vegetable oils, polyphenol, terpene, and other bio-renewable sources. With the aim to develop a new family of biobased polyurethanes (PUs) via vegetable oils, the elaboration of new Jojoba-based PUs was performed by catalyst-free polycondensation reaction of a synthesized Jojoba diol with various diisocyanates such us toluene diisocyanate… More > Graphic Abstract

    New Biobased Polyurethane Materials from Modified Vegetable Oil

  • Open Access

    ARTICLE

    Dielectric Permittivity of Rigid Rapeseed Oil Polyol Polyurethane Biofoams and Petrochemical Foams at Low Frequencies

    Ilze Beverte1,*, Vairis Shtrauss1, Aldis Kalpinsh1, Uldis Lomanovskis1, Ugis Cabulis2, Irina Sevastyanova2, Sergejs Gaidukovs3

    Journal of Renewable Materials, Vol.8, No.9, pp. 1151-1170, 2020, DOI:10.32604/jrm.2020.010215

    Abstract Early investigations of dielectric permittivity of rigid polyurethane foams at low frequencies were made on petrochemical-origin foams, mainly by means of parallel plate capacitors. In the present investigation biopolyol was synthesized from Latvia-grown rapeseeds’ oil by the transesterification method with triethanolamine, in an environmentally friendly process, without emission of harmful substances, at temperatures 175°C ± 5°C. Rigid, closed-cell rapeseed oil polyol polyurethane biofoams and petrochemical foams were made ensuring content of the renewable rapeseed oil polyol in ready foams 27 wt.%–29 wt.%. Dielectric permittivity of the polyurethane foams and the underlying monolithic petrochemical-origin polyurethane and biopolyurethane was measured with a… More >

  • Open Access

    REVIEW

    Plant Oil-Based Waterborne Polyurethanes: A Brief Review

    Verónica L. Mucci1, M. E. Victoria Hormaiztegui2, Mirta I. Aranguren1,*

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

    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 are soluble in organic solvents… More >

  • Open Access

    Synthesis of Novel Biobased Polyol via Thiol-Ene Chemistry for Rigid Polyurethane Foams

    N. Elbers1, C. K. Ranaweera1, M. Ionescu2, X. Wan2, P. K. Kahol3, Ram K. Gupta1,2*

    Journal of Renewable Materials, Vol.5, Suppl.1, pp. 74-83, 2017, DOI:10.7569/JRM.2017.634137

    Abstract The objective of this research is to prepare rigid polyurethane (PU) foams from α-phellandrene, a biobased compound. Two types of polyols were synthesized by reacting α-phellandrene with 2-mercaptoethanol and α-thioglycerol via thiol-ene chemistry route. The completion of the reaction was identified by using FTIR. PU foams from α-phellandrene polyols and commercial polyol were compared with regard to foam characteristics and properties. All the PU foams showed apparent density of 28–39 kg/m3 with closed-cell content above 90%. The highest glass transition temperature of 229 °C and compressive strength of 220 kPa were observed for the polyol synthesized by reacting α-phellandrene and… More >

  • Open Access

    Biobased Polyols Using Thiol-Ene Chemistry for Rigid Polyurethane Foams with Enhanced Flame-Retardant Properties

    C. K. Ranaweera1, M. Ionescu2, N. Bilic2, X. Wan2, P. K. Kahol3, Ram K. Gupta1,2*

    Journal of Renewable Materials, Vol.5, Suppl.1, pp. 1-12, 2017, DOI:10.7569/JRM.2017.634105

    Abstract Biobased polyol was synthesized using 1-thioglycerol and limonene, an extract of orange peel, via thiol-ene chemistry as an alternative to petrochemical-based polyol for preparation of rigid polyurethane foams (RPFs). Fire-retardant polyurethane foams were prepared by addition of different amounts of dimethyl methyl phosphonate (DMMP) in the polyol. The effect of DMMP on the properties of RPFs was studied. All the biobased RPFs maintained a regular cell structure with uniform cell distribution and over 90% of closed cell. The RPFs showed excellent compressive strength of ~230 kPa without addition of DMMP. These RPFs almost retained their specific compressive strength even when… More >

  • Open Access

    ARTICLE

    Lightweight Biobased Polyurethane Nanocomposite Foams Reinforced with Pineapple Leaf Nanofibers (PLNFs)

    Xiaojian Zhou1,2, Hui Wang1, Jun Zhang2, Zhifeng Zheng1, Guanben Du1,2,*

    Journal of Renewable Materials, Vol.6, No.1, pp. 68-74, 2018, DOI:10.7569/JRM.2017.634150

    Abstract Pineapple leaf nanofibers (PLNFs) extracted from pineapple leaf fiber were used for reinforcing biobased polyurethane foam (BPU). The dispersion performance of PLNF in the foaming mixture system, nanocomposite foaming behavior, cell morphology, cell size, density, compressive strength and dimensional stability were investigated. The viscosity of the mixtures increased with increasing the PLNF content. The addition of a tiny amount of PLNF did not influence the exothermic temperature of the foam system, but reduced the expansion and gel time of the nanocomposite foams. This reduced time was found to increase the production efficiency. Scanning electron microscopy (SEM) images showed that the… More >

  • Open Access

    ARTICLE

    Mixed-Ligand Ni(II), Co(II) and Fe(II) Complexes as Catalysts for Esterification of Biomass-Derived Levulinic Acid with Polyol and in Situ Reduction via Hydrogenation with NaBH4

    Md. Anwar Hossain1,2, Lee Hwei Voon1,*

    Journal of Renewable Materials, Vol.7, No.8, pp. 731-748, 2019, DOI:10.32604/jrm.2019.04703

    Abstract Synthesizing polyol-based ester from biomass feedstocks for the preparation of biolubricant overcomes the dependence on petroleum oil usage. Albeit biomass-derived bio-oil is an alternative for the production of polyol ester, upgrading is essential prior to use as biolubricant. Levulinic acid (LA), obtained from bio-oil was applied for the catalytic esterification with two polyols, e.g., trimethylolpropane (TMP) and pentaerythritol (PE), in the presence of mixed-ligand Ni(II), Co(II), and Fe(II) complexes as catalyst. New mixed-ligand coordination complexes with empirical formula; [Ni(Phe)(Bpy)Cl].H2O, [Co(Phe)(Bpy)Cl].H2O, and [Fe(Phe)(Tyr)Cl].H2O were synthesized by the reaction of ligands [L-phenylalanine (Phe), 4,4'-bipyridine (Bpy), and L-tyrosine (Tyr)] with metal chloride salts… More >

  • Open Access

    ARTICLE

    Liquefaction of Kraft Lignin at Atmospheric Pressure

    Silvia Helena Fuentes da Silva1, Patricia Soares Bilhalva dos Santos2, Darci Alberto Gatto3, Maria Angeles Andres1, Itziar Egüés1,*

    Journal of Renewable Materials, Vol.7, No.6, pp. 527-534, 2019, DOI:10.32604/jrm.2019.04291

    Abstract Kraft lignin was liquefied using polyethylene glycol #400 (PEG) and glycerol (G) in a weight ratio of 80/20 (w/w) and sulphuric acid (SA) as catalyst under atmospheric pressure at 160ºC. The three independent variables: reaction time (60, 80 and 100 min), percentage of lignin (15, 20 and 25%, w/w), and catalyst concentration (0, 3 and 6%, w/w), were varied resulting in 27 experimental runs. The effect of these reaction conditions on the properties of the polyols was evaluated. The statistical analysis showed that only “the percentage of lignin” did not influence the properties of the liquefied products, however, reaction time… More >

  • Open Access

    ARTICLE

    Synthesis and Characterization of Novel Castor Oil-Based Polyol for Potential Applications in Coatings

    Azam Sardari1,2, Ali Asghar Sabbagh Alvani1,2,3,*, Seyed Reza Ghaffarian1,2

    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 of saponified castor oil as… More >

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