Alexandr Arshanitsa^*, Matiss Pals, Daniela Godina, Oskars Bikovens

Journal of Renewable Materials, Vol.12, No.11, pp. 1927-1948, 2024, DOI:10.32604/jrm.2024.056466 - 22 November 2024

Abstract The isolated hydrophilic black alder (Alnus glutinosa) bark extractives were characterized in terms of component and functional composition and converted at 150°C–170°C into liquid green polyols using solvent-free and low-toxic base-catalyzed modification with propylene carbonate (PC). FTIR spectroscopy, HP-LC, GC, GPC, and wet chemistry methods were used to characterize the starting constituents, intermediate and final products of the reaction and to monitor the different pathways of PC conversion. The reaction of extractives as well as the model compounds, including catechol, xylose, PEG 400, and benzoic acid, with PC indicated the ability of OH groups of different… More > Graphic Abstract

Chenggang Liang^1,#, Chunyu Wei^1,#, Yan Wang^1,*, Wujuan Yu¹, Kai Liao¹, Taoxiong Shi¹, Dabing Xiang^2,3, Qijiao Chen¹

Phyton-International Journal of Experimental Botany, Vol.90, No.3, pp. 871-893, 2021, DOI:10.32604/phyton.2021.014242 - 30 March 2021

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… 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 >

Silvia Helena Fuentes da Silva¹, Patricia Soares Bilhalva dos Santos², Darci Alberto Gatto³, Maria Angeles Andres¹, Itziar Egüés^1,*

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 More >

Stephany C. de Rezende^1,2, João A. Pinto^1,3, Isabel P. Fernandes^1,3, Fernanda V. Leimann^1,2* and Maria-Filomena Barreiro^1,3*

Journal of Renewable Materials, Vol.6, No.7, pp. 715-723, 2018, DOI:10.32604/JRM.2018.00028

Abstract Pine-fruit shell (PFS) is a lignocellulosic residue derived from the fruit of Araucaria angustifolia, a coniferous tree native of South America, part of a whole vegetation of the Atlantic Forest, found in the South and Southwest of Brazil. In this work PFS will be characterized and used in the production of PFS-based polyols through oxypropylation. Three series were chosen (PFS/propylene oxide (PO) (w/v, g/mL) of 30/70, 20/80 and 10/90) with four catalyst levels (5%, 10%, 15% and 20%, (w/w, PFS based)). Oxypropylation occurred at moderate conditions of temperature, pressure and time giving rise to liquid… More >

Hynek Beneš, Aleksandra Paruzel*, Jiří Hodan and Olga Trhlíková

Journal of Renewable Materials, Vol.6, No.7, pp. 697-706, 2018, DOI:10.32604/JRM.2018.00011

Abstract In this study, castor oil, rapeseed oil and medium chain triglycerides of coconut oil, were transesterified by means of 2-ethyl-2-hydroxymethyl-1,3-propanediol (trimethylolpropane) and consequently used to convert polycarbonate waste from end-of-life vehicles into liquid polyols. The prepared recycled polyols, composed uniquely of renewable and recycled components, had a hydroxyl number of ca. 250 mg KOH·g−1. They were successfully applied as 100% replacement of a virgin polyol for preparation of solid crosslinked polyurethanes (PU) by solvent-free casting. The produced rigid cast PU exhibited the main transition temperature ranging from 44°C to 53°C, the hardness value from 46 More >

Maha L. Shrestha^1,2,*, Mihail Ionescu¹, Xianmei Wan¹, Thomas Upshaw³

Journal of Renewable Materials, Vol.6, No.6, pp. 630-641, 2018, DOI:10.7569/JRM.2018.634106

Abstract Aromatic-aliphatic polyols were obtained previously from the thiol-ene reactions of propoxylated cardanol with hydroxyalkyl mercaptans; these aromatic-aliphatic polyols were then utilized in the preparation of rigid polyurethane foams with excellent properties. The current work describes a variant of cardanol polyol synthesis by thiol-ene reactions in three steps. The first step is propoxylation of cardanol by reacting cardanol with propylene oxide; the second step is mercaptanization of propoxylated cardanol by reacting double bonds with hydrogen sulfide; and the third step involves the addition of the thiol groups of mercaptanized propoxylated cardanol to the double bonds of More >

Maha L. Shrestha^{1, 2,*}, Mihail Ionescu¹, Xianmei Wan¹, Zoran S. Petrović¹

Journal of Renewable Materials, Vol.6, No.5, pp. 504-516, 2018, DOI:10.7569/JRM.2017.634187

Abstract Biobased aromatic-aliphatic polyols were previously synthesized from a thermal thiol-ene reaction of propoxylated cardanol with 2-mercaptoethanol (ME) in the presence of azobisisobutyronitrile (AIBN) as a radical initiator. Cardanol used for this purpose was obtained as a dark-brown liquid (Gardner Color Reference ∼18). The photochemical thiol-ene reaction can also be used to prepare aromatic-aliphatic polyols by employing cardanol. Via the photochemical thiol-ene reaction, 2-mercaptoethanol was added successfully to C=C double bond of cardanol, suggesting that phenolic group may not play an inhibitory role in the radical thiol-ene reaction. However, we preferred to alkoxylate the phenolic hydroxyl More >

S. Michałowski¹, M. A. Mosiewicki^2*, M. Kuran´ska¹, M. I. Aranguren², A. Prociak¹

Journal of Renewable Materials, Vol.6, No.4, pp. 426-437, 2018, DOI:10.7569/JRM.2017.634163

Abstract Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils. The reference material was modified by replacement of the commercial polyol by 10% of biopolyols and also by addition of sisal fibers up to 5 wt%. The higher functionality of the biopolyols increased the crosslinking density of the networks and this was reflected by an increase in hardness and a decrease in water absorption. The effect of the sisal fibers mainly improved the mechanical and thermomechanical properties of the system with rapeseed oil because of good More >

Maha L. Shrestha¹, Mihail Ionescu^1*, Xianmei Wan¹, Nikola Bilić¹, Zoran S. Petrović¹, Tom Upshaw²

Journal of Renewable Materials, Vol.6, No.1, pp. 87-101, 2018, DOI:10.7569/JRM.2017.634153

Abstract Cardanol is a natural phenol which is obtained from high vacuum distillation of cashew nut shell liquid. It contains a hydrocarbon chain of 15 carbon atoms in the meta position, either with one, two or three non-conjugated double bonds. This article describes thermal thiol-ene reaction to synthesize new cardanol-based polyols for polyurethanes with aromatic-aliphatic structure. Phenolic hydroxyl group was blocked by alkoxylation and 2-mercaptoethanol was added to the double bonds of propoxylated cardanol. The resultant product is a mixture of polyols that may contain one, two, three or four hydroxyl groups, as a function of the More >