Abeer M. Adel¹, Amira M. El-Shafei², Atef A. Ibrahim¹, Mona T. Al-Shemy^1,*

Journal of Renewable Materials, Vol.7, No.6, pp. 567-582, 2019, DOI:10.32604/jrm.2019.00034

Abstract In this study, nanocrystalline celluloses were used to enhance physical, mechanical and water vapor barrier properties of chitosan films for potential food packaging applications. Two different mineral acids (sulfuric and phosphoric) were used to extract nanocrystalline cellulose from date palm sheath fibers. The influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses (e.g., yield, energy and length of intra- and intermolecular hydrogen bonds, and degree of substitution) were studied too. The characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline cellulose. Results showed that besides cellulose polymorphism,… More >

Marcia Cristina Branciforti^1,*, Caroline Faria Bellani², Carolina Lipparelli Morelli², Alice Ferrand³, Nadia Benkirane-Jessel³, Rosario Elida Suman Bretas²

Journal of Renewable Materials, Vol.7, No.3, pp. 269-277, 2019, DOI:10.32604/jrm.2019.01833

Abstract Although nanocomposites have recently attracted special interest in the tissue engineering area, due to their potential to reinforce scaffolds for hard tissues applications, a number of variables must be set prior to any clinical application. This manuscript addresses the evaluation of thermo-mechanical properties and of cell proliferation of cellulose nanocrystals (CNC), poly(butylene adipate-co-terephthalate) (PBAT), poly(ε-caprolactone) (PCL) films and their bionanocomposites with 2 wt% of CNC obtained by casting technique. Cellulose nanocrystals extracted from Balsa wood by acid hydrolysis were used as a reinforcing phase in PBAT and PCL matrix films. The films and pure CNC at different concentrations were cultured… More >

Fatima Ezzahra El Abbassi^1,*, Mustapha Assarar², Rezak Ayad², Hamid Sabhi², Stephane Buet², Nouzha Lamdouar³

Journal of Renewable Materials, Vol.7, No.3, pp. 253-267, 2019, DOI:10.32604/jrm.2019.01759

Abstract This paper aims at studying the effect of recycling on the static and dynamic properties of short alfa fibre reinforced polypropylene. For this purpose, alfa fibres reinforced composites were elaborated by an injection moulding process and were subjected to different mechanical recycling cycles. Then, non-recycled and recycled materials were subjected to static tests and Dynamic Mechanical Analysis (DMA) to evaluate the effect of recycling on their behaviour. Besides, the effects of alkali and salt water treatments on the static and dynamic properties of the alfa composite were also investigated. The obtained results show that tensile and flexural properties of alfa… More >

Ana Clara Lancarovici Alves, Rafael Grande, Antonio José Felix Carvalho^*

Journal of Renewable Materials, Vol.7, No.3, pp. 245-252, 2019, DOI:10.32604/jrm.2019.00833

Abstract The interest in thermoplastic starch (TPS) as a substitute material to replace conventional thermoplastics continues especially due its biodegradability, availability, low cost and because it is obtained from renewable sources. However, its poor mechanical properties and its high sensitivity to humidity have limited its use in several applications. Here, the copolymer poly (ethylene-co-vinyl alcohol) (EVOH), with two different ethylene contents, 27 and 44 mol% were blended with TPS by extrusion in order to overcome these limitations. The obtained blends were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), mechanical tensile testing, Scanning Electron Microscopy (SEM) and moisture absorption test.… More >

Paula do Patrocínio Dias, Marcelo Aparecido Chinelatto^*

Journal of Renewable Materials, Vol.7, No.2, pp. 129-138, 2019, DOI:10.32604/jrm.2019.00037

Abstract In this study a low molecular weight triblock copolymer derived from ε-caprolactone and tetrahydrofuran was used as a non-reactive compatibilizer of immiscible PLA/PCL blends. Ternary blends with 0, 1.5 wt%, 3 wt% and 5 wt% copolymer and about 75 wt% PLA were prepared by single screw extrusion and characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), tensile and Izod impact testing. SEM micrographs showed that the size of the dispersed PCL domains was practically constant regardless of copolymer concentration. This result can be explained by the low shear rate employed during processing step and… More >

B. Benobeidallah¹, A. Benhamida¹, A. Dorigato^2,*, A. Sola³, M. Messori³, A. Pegoretti²

Journal of Renewable Materials, Vol.7, No.1, pp. 89-102, 2019, DOI:10.32604/jrm.2019.00136

Abstract Various amounts (up to 10 wt%) of palygorskite nanofibers functionalized by 3-aminopropyltriethoxysilane (APTES) coupling agent were used to reinforce polyamide 11 nanocomposites prepared by melt compounding. The covalent bonding of the silane on the palygorskite surface was confirmed by infrared spectroscopy and thermogravimetric analysis. X-ray diffraction revealed the retention of the α-form of polyamide crystals upon the addition of both natural and silane treated palygorskite nanorods. All the investigated nanocomposites showed an improvement of the thermal stability, especially when surface treated palygorskite nanofibers were considered. Tensile tests and dynamic mechanical thermal analyses on the prepared materials evidenced how the incorporation… More >

Yang Yu¹, Ramiz Boy^1,2,*, Richard Kotek¹

Journal of Renewable Materials, Vol.7, No.1, pp. 41-55, 2019, DOI:10.32604/jrm.2019.00105

Abstract Current industrial methods for dissolution of cellulose in making regenerated cellulose products are relatively expensive, toxic and dangerous and have environmental problems coming with the hazard chemical wastes. To solve these problems, a novel ethylenediamine and potassium thiocyanate (ED/KSCN) solvent system was developed, that is economical, ecofriendly, and highly efficient. The ED/KSCN solvent system was proven to be a suitable solvent for fabricating cellulose (blended with other polymers) membranes. In this study, gluten was used to develop nonporous membranes with cellulose. The method of casting these membranes provided better ones than the former researchers’ techniques. These composite membranes’ physical and… More >

Dan-Thuy Van-Pham^1,*, 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 >

Haitao Wang¹, Zhenhan Yao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.7, No.1, pp. 85-96, 2005, DOI:10.3970/cmes.2005.007.085

Abstract This paper addresses a new boundary element method (BEM) for the numerical analysis of mechanical properties in 3D particle-reinforced composites. The BEM is accelerated by a new version fast multipole method (FMM) in order to perform large scale simulation of a representative volume element (RVE) containing up to several hundred randomly distributed elastic spherical particles on only one personal computer. The maximum number of degrees of freedom (DOF) reaches more than 300,000. Efficiency of the developed new version fast multipole BEM code is evaluated compared with other conventional solutions for BEM. The effects of micro-structural parameters, namely the particle size,… More >

Andrea Dorigato^1,*, Martino Negri², Alessandro Pegoretti^1,*

Journal of Renewable Materials, Vol.6, No.5, pp. 493-503, 2018, DOI:10.7569/JRM.2017.634177

Abstract Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch (TPS) matrices. The microstructure and physical properties of the resulting unidirectional and bidirectional laminates were studied. The investigated materials presented a complex microstructure, in which the porosity of the wood laminae was almost entirely occluded by the polymer matrix. The mechanical behavior of the laminates was strongly affected by the obtained microstructure, and matrix penetration in wood pores led to biodegradable composites with elastic modulus and tensile strength higher than those of their constituents. Finally, thermal welding… More >