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  • 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 More >

  • Open Access

    ARTICLE

    Viscoelastic and Thermal Properties of Polyurethane Foams Obtained from Renewable and Recyclable Components

    S. Gaidukovs1,2,*, G. Gaidukova2, A. Ivdre1,3, U. Cabulis3

    Journal of Renewable Materials, Vol.6, No.7, pp. 755-763, 2018, DOI:10.7569/JRM.2018.634112

    Abstract This article deals with the study of the viscoelastic and thermal properties of polyurethane (PU) rigid foams from biobased and recycled components. Rapeseed oil (RO) and recycled poly(ethylene terephthalate) (PET) were used to synthesize PU polyols. Addition of adipic acid (ADA) to polyol resulted in improved thermal and viscoelastic properties of foam materials. ADA content was varied from 1 to 6 wt%. Results of the dynamic mechanical spectra indicate an increase of the storage modulus E′ and the loss modulus E″ in the whole temperature range for specimens with higher loading of ADA. In addition, More >

  • Open Access

    ARTICLE

    Application of Amine-Functionalized Cellulose Foam for CO2 Capture and Storage in the Brewing Industry

    Lars Helmlinger1, Yejun Zhu1, Julia Gensel1, Thomas Neumeyer1, Stefan Thäter2, Franziska Strube2, Christoph Bauer2, Bernd Rosemann2, Volker Altstädt1*

    Journal of Renewable Materials, Vol.6, No.3, pp. 219-225, 2018, DOI:10.7569/JRM.2017.634161

    Abstract Due to a lack of technology, smaller breweries simply dump excess CO2 into the atmosphere, fueling the greenhouse effect and global warming. State-of-the-art CO2 capture technologies using nanofibrillated cellulose are expensive and require laborious freeze-drying. Consequently, there is a high demand for affordable alternatives in order to reduce the environmental impact in this industry sector. This work describes a novel route for a quick and cost-efficient synthesis of amine-functionalized cellulose pellets by a surfactant-assisted steam explosion process. Typical values with this method were porosity of 92% and density of 67 g/cm³. Investigations on polyethylenimine (PEI) 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

    Variation of Physical Properties of Rigid Polyurethane Foams Synthesized from Renewable Sources with Different Commercial Catalysts

    Daniel Brenes-Granados1, Jorge M. Cubero-Sesin1,2, Felipe Orozco Gutiérrez3, Jose Vega-Baudrit3, Rodolfo Gonzalez-Paz3*

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 280-289, 2017, DOI:10.7569/JRM.2017.634118

    Abstract In this work, rigid polyurethane foams were synthesized from renewable sources using different catalysts to study their effect on the mechanical, thermal, chemical and surface properties of the foams. A commercial foam pattern was used as the reference pattern to compare the aforementioned properties. Concentrations of the commercial catalysts were optimized to obtain foams with similar mechanical properties to the commercial foam. Morphological characterization of the foams was performed by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) spectroscopy was employed to investigate the characteristic functional groups. Thermal characterization was performed by means of differential 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

    New Closed- and Open-Cell, Aldehyde-Free Protein Foams

    María Cecilia Basso1*, Antonio Pizzi1,2

    Journal of Renewable Materials, Vol.5, No.1, pp. 48-53, 2017, DOI:10.7569/JRM.2016.634124

    Abstract New aldehyde-free and isocyanate-free biofoams have been obtained by reacting albumin chicken egg white and dimethyl carbonate (DMC). The optimized formulations yielded lightweight foams whose densities were evaluated as 0.016–0.16 g/cm3. Mechanical resistance was 0.023–0.34 MPa and residual pH nearly neutral. The new foams presented up to 57% of closed cells as measured by helium pycnometry and good thermal insulation. These new natural foams are environmentally friendly materials and show very promising properties. More >

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