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  • Open Access

    ARTICLE

    Development of Cardanol-Based Polyol via Click Chemistry and Crosslinking with Melamine Formaldehyde Resin for Coating Applications

    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 More >

  • Open Access

    ARTICLE

    Polyurethane Composites Synthesized Using Natural Oil-Based Polyols and Sisal Fibers

    S. Michałowski1, M. A. Mosiewicki2*, 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 >

  • Open Access

    ARTICLE

    Biobased Aromatic-Aliphatic Polyols from Cardanol by Thermal Thiol-Ene Reaction

    Maha L. Shrestha1, Mihail Ionescu1*, 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 >

  • 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 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… More >

  • Open Access

    ARTICLE

    Rapeseed Oil as Feedstock for High Functionality Polyol Synthesis

    M. Kirpluks1*, D. Kalnbunde1, Z. Walterova2, U. Cabulis1

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 258-270, 2017, DOI:10.7569/JRM.2017.634116

    Abstract In this study, polyols with high average functionality were synthesized from a renewable resource, rapeseed oil, as raw material for rigid PU foam production. A well-known method of rapeseed oil fatty acid double bond epoxidation was used to introduce oxirane rings into rapeseed oil structure. The temperature influence on epoxidation reaction conversion rate was studied by volumetric and FTIR spectra analysis. After epoxidation of rapeseed oil, an oxirane ring-opening reaction was carried out to obtain high functionality polyols. Diethylene glycol, a conventional oxirane ring-opening reagent, was compared to amine-based polyfunctional alcohols, diethanolamine and triethanolamine. The More >

  • Open Access

    ARTICLE

    Thermal-Mechanical Characterization of Polyurethane Rigid Foams: Effect of Modifying Bio-Polyol Content in Isocyanate Prepolymers

    Luis Daniel Mora-Murillo1, Felipe Orozco-Gutierrez2, José Vega-Baudrit2, Rodolfo Jesús González-Paz2*

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 220-230, 2017, DOI:10.7569/JRM.2017.634112

    Abstract Nowadays, green polyurethane (PU) foams are mostly synthesized by replacing an amount of petrochemical polyol with biobased polyol. Here we report five different families of isocyanate prepolymer formulations that were prepared with biobased sources and the correlation between the structure of chains and the properties of the produced PU foam. Foam behavior in tension, torsion, compression, shape memory tests and physical properties were studied by dynamic mechanical thermal analysis (DMTA); interactions in the polymer chains were analyzed by Fourier transform infrared spectroscopy (FTIR); and thermal analysis was performed by thermogravimetry (TGA) and differential scanning calorimetry More >

  • Open Access

    ARTICLE

    Karanja Oil Polyol and Rigid Polyurethane Biofoams for Thermal Insulation

    M. Himabindu1, K. Kamalakar2, MSL Karuna2, Aruna Palanisamy1*

    Journal of Renewable Materials, Vol.5, No.2, pp. 124-131, 2017, DOI:10.7569/JRM.2016.634137

    Abstract Rigid polyurethane biofoams were prepared from karanja polyol which was derived by ring-opening reaction of epoxidized karanja oil. The polyol, which had a hydroxyl value of 186 mg KOH/g, was thoroughly characterized and the structure confirmed by spectral techniques. The foam formulations were developed to achieve shrinkage-free foams with water used as the blowing agent. The resulting foams were characterized for their mechanical properties like density, compression strength and flexural strength. The densities and mechanical properties, such as compression and flexural strength, varied with the amount of methylene diphenyl diisocyanate (MDI) for a fixed amount More >

  • Open Access

    ARTICLE

    Polyol Preparation by Liquefaction of Technical Lignins in Crude Glycerol

    Louis C. Muller1*, Sanette Marx1, Hermanus C.M. Vosloo2

    Journal of Renewable Materials, Vol.5, No.1, pp. 67-80, 2017, DOI:10.7569/JRM.2016.634130

    Abstract This work reports a study of polyol synthesis through liquefaction of technical lignins in crude glycerol by means of 1H and 31P NMR spectroscopy. The polyols are intended for preparation of polyurethane foam; thus, it is important to know how different lignin types as well as crude glycerol influence and contribute to the final polyol hydroxyl contents. Polyols prepared from organosolv lignin, kraft lignin and lignosulphonate had hydroxyl numbers suitable for rigid foam of 435, 515 and 529 mgKOH/g, respectively. The polyols differed in composition with glycerol, showing significant variation. During liquefaction the glycerol content More >

  • Open Access

    ARTICLE

    Polyols Based on Poly(ethylene terephthalate) and Tall Oil: Perspectives for Synthesis and Production of Rigid Polyurethane Foams

    A. Ivdre1*, G.D. Soto2, U. Cabulis1

    Journal of Renewable Materials, Vol.4, No.4, pp. 285-293, 2016, DOI:10.7569/JRM.2016.634122

    Abstract This study presents the synthesis of novel polyols made from tall oil (TO) and poly(ethylene terephthalate) (PET) with different TO/PET molar ratios. Rigid polyurethane foams based on these synthesized polyols were obtained and characterized to evaluate polyols’ suitability for the development of light materials with insulating properties. The effect of TO/PET molar ratios on the physical, morphological and mechanical properties of the obtained foams, as well as their thermal insulation characteristics, were evaluated. Increasing amounts of PET in polyurethane foams resulted in higher compression strength and closed cell content, while water absorption was not affected. More >

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