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 of saponified castor oil as… 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 of coatings, mechanical tests and… 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 polyols with a homopolymer content… 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 to 61 Shore D and… More >

Edgars Vanags*, Mikelis Kirpluks, Ugis Cabulis and Zuzana Walterova

Journal of Renewable Materials, Vol.6, No.7, pp. 764-771, 2018, DOI:10.7569/JRM.2018.634111

Abstract In this work, free tall oil fatty acids were epoxidized with in-situ generated peroxyacetic acid. Reaction kinetics of epoxidation was investigated by oxirane content and iodine value titrimetric determination, as well as FTIR spectra analysis. A highly functional biobased polyol was synthesized by functionalizing epoxidized tall oil fatty acids with triethanolamine using Montmorillonite K10 as a catalyst. The obtained polyol was analyzed by FTIR and MALDI-TOF MS. The most common chemical and physical characteristics of obtained polyol were determined. 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 allyl alcohol, glycerol-1-allyl ether, and… 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 group of cardanol, which is… More >

Kunal Wazarkar, Anagha Sabnis*

Journal of Renewable Materials, Vol.6, No.4, pp. 438-449, 2018, DOI:10.7569/JRM.2017.634159

Abstract The research work presented in this article deals with the synthesis of cardanol-based polyol and its curing with hexabutoxymethyl melamine (HBMM) for application in coatings. Cardanol-based polyol was prepared via thiol-ene click reaction using thioglycerol. Unsaturation present in the long chain of cardanol was successfully utilized to synthesize polyol via thiol-ene coupling. The reaction was carried out between cardanol and thioglycerol in the presence of Irgacure 184 (photoinitiator) and 1,8-Diazabicyclo[5.4.0]undec-7-ene (catalyst) under UV light for 12 h at 80 °C. After completion of the reaction, one mole of thioglycerol was successfully added across the double bond of a fatty chain… 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 dispersion and strong fiber-matrix interaction.… 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 number of double bonds… More >