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  • Open Access

    ARTICLE

    Influence of Isocyanate Index on Selected Properties of Flexible Polyurethane Foams Modified with Various Bio-Components

    Aleksander Prociak*, Elźbieta Malewska, Szymon Bąk

    Journal of Renewable Materials, Vol.4, No.1, pp. 78-85, 2016, DOI:10.7569/JRM.2015.634129

    Abstract In this article, the results of the foaming process analysis of fl exible polyurethane with different isocyanate indexes are presented. Two types of flexible polyurethane foams (FPURF) were obtained: (1) by using petrochemical components and a rapeseed-oil-based polyol (used in the amount of 20 wt%), (2) by using petrochemical components and cellulose as a natural fi ller in the amount of 3 php (per hundred parts of polyol). The characteristic parameters of the foaming process, such as the foam’s growth velocity, the core temperature and dielectric polarization, were measured using a Foamat device. Moreover, the following properties of flexible polyurethane… More >

  • Open Access

    ARTICLE

    Synthesis, Structure and Properties of Poly(ester-Urethane- Urea)s Synthesized Using Biobased Diamine

    Marcin Włoch, Janusz Datta*

    Journal of Renewable Materials, Vol.4, No.1, pp. 72-77, 2016, DOI:10.7569/JRM.2015.634130

    Abstract Modern polymer science and technology is focused on the development of partial or fully green polymers. This focus is related to green chemistry trends, which propose using natural and renewable resources as monomers in the synthesis of polymers. In this study, biobased diamine was used as a chain extender of ester-urethane prepolymer. Obtained poly(ester-urethane-urea) contains 16 wt% of biobased diamine. There is mention of an amine curing agent that is an amine derivative of dimerized fatty acids (obtained from vegetable oils). Application of two chain extenders, i.e., 1,4-butanediol and biobased diamine (applied separately or in mixture), with different molecular weights… More >

  • Open Access

    ARTICLE

    Biodegradation Pretreatment of Wood of E. grandis, E. dunnii, and E. benthamii to Work in Biorefi nery Processes

    Mary Isabel Lopretti1,2*, Natalia Irene Baldyga3, Maria Gonzalez1, Laura Beatriz Olazabal3, Marina Graciela Torres3, Fernando Resquin4, Leonidas Carrasco4

    Journal of Renewable Materials, Vol.4, No.1, pp. 66-71, 2016, DOI:10.7569/JRM.2015.634133

    Abstract Nowadays, there is a great interest in using lignocellulosic materials as substrate for the production of biorefi nery products. Eucalypti are good options to use as crops to obtain different kinds of biofuels and derivatives, since their plantations show high adaptation potential to soil and weather conditions in Uruguay. The basic process steps involved in the obtainment of biorefi nery materials are: pretreatment, hydrolysis, fermentation and products separation. As delignifi cation is an important process to obtain biorefi nery products, in this context the evaluation of the biological (BT) and hydrothermal (TT) pretreatment of different species of Eucaliptus was studied.… More >

  • Open Access

    ARTICLE

    Improved Permeability Properties for Bacterial Cellulose/ Montmorillonite Hybrid Bionanocomposite Membranes by In-Situ Assembling

    Itxaso Algar1, Clara Garcia-Astrain1, Alba Gonzalez2, Loli Martin3, Nagore Gabilondo1, Aloña Retegi1*, Arantxa Eceiza1*

    Journal of Renewable Materials, Vol.4, No.1, pp. 57-65, 2016, DOI:10.7569/JRM.2015.634124

    Abstract Bacterial cellulose/montmorillonite (BCMMT) hybrid bionanocomposite membranes were prepared by in-situ assembling or one-step biosynthesis process. The presence of MMT in BC membranes was confi rmed by thermogravimetric analysis and quantifi ed by mass spectrometry, resulting in bionanocomposites with MMT contents between 7–13 wt%. The incorporation of MMT during BC biosynthesis modifi ed BC morphology and led to lower porosity, even though higher water holding capacity was achieved. Bionanocomposites showed improved thermal stability and water vapor and oxygen gas barrier properties up to 70 and 80% with respect to neat BC membranes. This improvement was related to the tortuous path of… More >

  • Open Access

    ARTICLE

    Biobased Additives as Biodegradability Enhancers with Application in TPU-Based Footwear Components

    Isabel Patrícia Fernandes1, Mariana Barbosa1, Joana Soares Amaral2, Vera Pinto3, José Luís Rodrigues3, Maria José Ferreira3, Maria Filomena Barreiro1*

    Journal of Renewable Materials, Vol.4, No.1, pp. 47-56, 2016, DOI:10.7569/JRM.2015.634126

    Abstract Among the wide variety of materials employed in the manufacture of shoes, thermoplastic polyurethanes (TPUs) are one of the most widely used. Given its widespread use, and associated waste management problems, the development of more biodegradable and evironmentally compatible solutions is needed. In this work, a polyester-based TPU used in the footwear industry for outsoles production was modifi ed by compounding with lignin, starch and cellulose at content of 4% (w/w). The biodegradability was evaluated by using agar plate tests with the fungi Aspergillus niger ATCC16404, the Gram-negative bacteria Pseudomonas aeruginosa ATCC9027 and an association of both (consortium), and soil… More >

  • Open Access

    ARTICLE

    Natural Additive for Reducing Formaldehyde Emissions in Urea-Formaldehyde Resins

    Flávio Pereira1, João Pereira2, Nádia Paiva3, João Ferra3, Jorge Manuel Martins1,4, Fernão D. Magalhães1, and Luísa Carvalho1,4*

    Journal of Renewable Materials, Vol.4, No.1, pp. 41-46, 2016, DOI:10.7569/JRM.2015.634128

    Abstract This work studies the use of soy protein as a natural formaldehyde scavenger in wood particleboard production. The protein is incorporated in two forms: a) as a powder, during the blending process of wood particles with urea-formaldehyde binder resin, and b) as an aqueous solution, added at different times during resin synthesis. Analysis of variance (ANOVA) was used to evaluate the signifi cance level of two effects (amount of added soy and time of addition) on internal bond strength, thickness swelling, and formaldehyde content of the resulting panels. The results showed that soy protein can contribute to decrease the formaldehyde… More >

  • Open Access

    ARTICLE

    Superhydrophobic and Oleophobic UV-Curable Surface Engineering of Cellulose-Based Substrates

    José M. R. C. A. Santos*, Ana R. Sampaio, Joana Branquinho

    Journal of Renewable Materials, Vol.4, No.1, pp. 31-40, 2016, DOI:10.7569/JRM.2015.634123

    Abstract Cellulose-based materials are one of the most widely used materials provided by nature to mankind. In particular, cotton fi bers have been used for millennia to produce clothing items. This wide usage stems from the inherent properties of cotton fabrics such as hydrophilicity and permeability to water vapor. However, increasingly sophisticated uses for cotton-based clothing (e.g., technical textiles) demand specifi c properties such as hydrophobicity and oleophobicity for repellent functions. The current surface treatments used to attain these functionalities are based on thermally initiated polymerization reactions, using water-based formulations. Thus, the current technologies are energy- and water-intensive. The advantages of… More >

  • Open Access

    ARTICLE

    Ultrasound-Assisted Synthesis of Sucrose and Fructooligosaccharides Esters as Bio-Plasticizers

    Dragomir Vassilev1*, Nadezhda Petkova2, Milena Koleva1, Panteley Denev2

    Journal of Renewable Materials, Vol.4, No.1, pp. 24-30, 2016, DOI:10.7569/JRM.2015.634125

    Abstract This article presents the results obtained by the ultrasound-assisted synthesis of sucrose and fructooligosaccharides (FOS) esters with fatty acids (palmitic and 10-undecylenic), the identifi cation of the products and the study of their possible application as plasticizers in plastics processing. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H and 13C NMR) spectroscopy were used to identify the synthesized carbohydrate esters. The plasticizing effect of the sucrose palmitate applied in polyvinyl chloride (PVC) was evaluated by the glass transition temperatures; the decrease of the Tg with the increase of the ester content could be accepted as confi rmation of… More >

  • Open Access

    ARTICLE

    Polymers from Biobased-Monomers: Macroporous Itaconic Xerogels Prepared in Deep Eutectic Solvents

    Szczepan Bednarz*, Angelika Wesołowska, Magdalena Trątnowiecka, Dariusz Bogdał

    Journal of Renewable Materials, Vol.4, No.1, pp. 18-23, 2016, DOI:10.7569/JRM.2015.634131

    Abstract New methods of preparation of crosslinked polymers from itaconic acid as a renewable monomer have been explored. Synthesis of hydrogels and xerogels from the acid in deep eutectic solvents (DESs) are described and some basic properties of the materials are reported. Most importantly, a surfactant-free method of creation of macroporous poly(itaconic-co-bisacrylamide) by phase separation polymerization in binary mixture of the DES and poly(ethylene glycol) is demonstrated. More >

  • Open Access

    ARTICLE

    Preparation of β-Cyclodextrin/Latex Dispersion for Coating of Cellulose Fabric

    Monique de Alvarenga Pinto Cotrim1*, Jessyca Aparecida Paes Dutra2, Suzana Gonçalves Carvalho2, Janaina Cecília Oliveira Villanova2, Eliane Ayres1

    Journal of Renewable Materials, Vol.4, No.1, pp. 9-17, 2016, DOI:10.7569/JRM.2015.634122

    Abstract In recent years there has been an increasing demand for the application of natural products to address problems in the environment. The use of products derived from renewable resources can provide a sustainable strategy to replace totally or partially synthetic products. Cymbopogon, commonly known as lemongrass, is a tropical grass cultivated mostly for its essential oil, which has demonstrated several bioactivities, including antibacterial and antifungal properties. In the present work the formation of inclusion complex between β-cyclodextrin (β-CD) and lemongrass essential oil (LGEO) as well as its fi xation onto cotton fabric were investigated. Inclusion complex was prepared through solution… More >

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