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  • Open Access

    ARTICLE

    Oxypropylation of Brazilian Pine-Fruit Shell Evaluated by Principal Component Analysis

    Stephany C. de Rezende1,2, João A. Pinto1,3, Isabel P. Fernandes1,3, Fernanda V. Leimann1,2* and Maria-Filomena Barreiro1,3*

    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 >

  • Open Access

    ARTICLE

    Microwave Synthesis of Inulin Acetate as Potential Bio-Based Additive for Poly(Vinyl Chloride)

    D. Vassilev1,*, N. Petkova2, M. Koleva1, P. Denev2

    Journal of Renewable Materials, Vol.6, No.7, pp. 707-714, 2018, DOI:10.32604/JRM.2018.00015

    Abstract The paper presents the findings of an experimental study on the microwave synthesis (MW) of inulin acetate and its possible application as bio-additive in poly(vinyl chloride) (PVC). The obtained inulin acetate has been identified and characterized by spectroscopic methods. Advantages of the MW compared with the conventional synthesis were defined. In order to evaluate possible application of the product as bio-based additive for polymers, effect of the inulin ester on PVC behavior and characteristics has been investigated by differential scanning calorimetry (DSC) and deformation upon extension. Experimental results show that in concentration range up to 30.0 wt. % the inulin… More >

  • Open Access

    ARTICLE

    Impact of Natural Oil-Based Recycled Polyols on Properties of Cast Polyurethanes

    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 >

  • Open Access

    ARTICLE

    Sustainable Materials Based on Cellulose from Food Sector Agro-Wastes

    T. Côto1, I. Moura1, A. de Sá1,*, C. Vilarinho2, A. V. Machado1

    Journal of Renewable Materials, Vol.6, No.7, pp. 688-696, 2018, DOI:10.32604/JRM.2018.00006

    Abstract Biopolymers exhibit unique properties and can be produced from plants’ and crops’ wastes. Cellulose has been used for the production of sustainable materials, nevertheless due to the difficulty inherent to its extraction, several methods have been studied in order to optimize the process. Therefore, this paper reports the extraction of natural polymers from food sector agro-food wastes, including cellulose, following a green chemistry aproach. The cellulose extracted from pumpkin peel was acetylated and dispersed in a polylactic acid (PLA) matrix. The developed materials were characterized in terms of their structure, morphology and thermal stability. The results demonstrated the efficient chemical… More >

  • Open Access

    ARTICLE

    Novel Approaches of Using of Spirulina Platensis in Natural Rubber Based Composites

    Ewa Głowińska*, Janusz Datta, Paulina Parcheta and Natalia Kaźmierczak

    Journal of Renewable Materials, Vol.6, No.7, pp. 680-687, 2018, DOI:10.32604/JRM.2018.00003

    Abstract The aim of this work was to investigate the influence of Spirulina (Spirulina platensis) as a natural filler on the curing characterization, morphology and mechanical, thermomechanical and thermal properties of natural rubber (NR) based composites. Spirulina was introduced into NR mixture in amount of 0 phr, 10 phr and 30 phr. The vulcanization process was carried out at the determined process condition by using hydraulic press at optimum vulcanization time (t90). It was noticed that Spirulina affected on the reduction of t90, and scorch time (t2) of the NR mixtures. Obtained vulcanizates were subjected to the number of tests e.g.… More >

  • Open Access

    ARTICLE

    Microwave-Assisted Isolation and Acetylation of Inulin from Helianthus Tuberosus L Tubers

    Nadezhda Petkova1,*, Gergana Gencheva1, Dragomir Vassilev2, Milena Koleva2, Albert Krastanov3, Panteley Denev1

    Journal of Renewable Materials, Vol.6, No.7, pp. 671-679, 2018, DOI:10.32604/JRM.2018.00001

    Abstract Jerusalem artichoke (Helianthus tuberosus L.) tubers are industrial crop considered as a promising source for inulin production. “Green” method was performed for accelerated inulin extraction from Helianthus tuberosus L. tubers by the application of microwave irradiation. Further pretreatment of the water extract with acetone and ethanol yielded inulin (20%) with purity 89% and degree of polymerization 18. Jerusalem artichoke inulin was characterized by FTIR and NMR spectroscopy. For the first time eco-friendly synthesis of acetylated Jerusalem artichoke inulin was performed by the reaction with acetic anhydride, without toxic solvent, but only with sodium acetate as catalyst under microwave irradiation for… More >

  • Open Access

    ARTICLE

    Poly(phenylene oxide) and Renewable Polyamide 11 Blends Compatibilized by Ethylene-n-Octene Copolymer

    Regina Jeziorska*, Agnieszka Abramowicz, Agnieszka Szadkowska, Anna Pasnik and Ewa Spasowka

    Journal of Renewable Materials, Vol.6, No.7, pp. 772-783, 2018, DOI:10.7569/JRM.2018.634114

    Abstract Poly(phenylene oxide)/renewable polyamide 11 (PPO/PA11 20/80) blends toughened with glycidyl methacrylate grafted ethylene-n-octene copolymer (GEOC) were prepared in a co-rotating twin-screw extruder. The reaction between GEOC and PPO/PA11 blend was analyzed by gel content tests. The morphology of PPO/PA11/GEOC blends was observed by scanning electron microscope. The SEM results showed that PPO formed the continuous phase, though it is a minority component of blends. With increasing GEOC content from 5 to 15 wt% the morphology of the blends transformed from droplet-matrix to co-continuous structure, in which both PA11 and PPO phases are continuous. The blend with co-continuous morphology had better… More >

  • Open Access

    ARTICLE

    Highly Functional Polyol Synthesis from Epoxidized Tall Oil Fatty Acids

    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 >

  • 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, damping factor shifted to higher… More >

  • Open Access

    ARTICLE

    Effects of Processing Parameters on Mechanical Properties and Structure of Banana Fiber-Reinforced Composites

    Dan-Thuy Van-Pham1,*, Minh Tri Nguyen1, Chanh-Nghiem Nguyen2, Thi Truc Duyen Le1, Thi Yen Nhu Pham1, Khai Thinh Nguyen2, Yukihiro Nishikawa3, Qui Tran-Cong-Miyata3

    Journal of Renewable Materials, Vol.6, No.6, pp. 662-670, 2018, DOI:10.7569/JRM.2018.634107

    Abstract The mechanical properties of unidirectional natural fiber-reinforced composites are generally affected by several processing parameters during compression molding. This study investigates the effects of processing temperature, time, and pressure on the tensile and flexural properties of acrylonitrile butadiene styrene reinforced by banana fibers. X-ray CT imaging was employed to find the relationship between the mechanical properties and structure of the processed composite. Besides, the water absorption of composites was observed and the way in which the mechanical properties evolved after water absorption was analyzed. The tensile and flexural properties of the unidirectional banana fiber-reinforced composite were found to be inversely… More >

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