Hao Dou^1,2,*, Hongxia Liu^1,2, Feng Wang^1,2, Yanli Sun^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 629-638, 2021, DOI:10.32604/fdmp.2021.015612

Abstract Electrospinning is a versatile and popular method for the fabrication of ultrafine fibers and many parameters in electrospinning can be adjusted when ideal micro/nanofibers are required. In particular, the selection of a proper solvent condition is a fundamental and crucial step to produce electrospun ultrafine fibers. In this study, a commonly used biomaterial, polylactic acid (PLA), was dissolved in 7 different solvents and PLA micro/nanofibers were prepared by electrospinning. The morphology, porosity, mechanical property and static contact angle were characterized to determine the quality of the obtained product. The results show that different solvent conditions have a significant effect on… More >

Ewa Szefer^*, Agnieszka Leszczyńska, Edyta Hebda, Krzysztof Pielichowski

Journal of Renewable Materials, Vol.9, No.6, pp. 1127-1142, 2021, DOI:10.32604/jrm.2021.014584

Abstract The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement. A series of all-bionanocomposites containing unmodified and surface modified cellulose nanocrystals with CNC content in the range of 1–3 %_w.t. were obtained by melt blending and tested by XRD, SEM, DSC and DMA to investigate the effect of surface esterification of CNCs on the structure, morphology, dynamic mechanical properties of bionanocomposites, as well as phase transitions of PLA in the presence of cellulosic nanofiller. DMA investigations showed the… More > Graphic Abstract

Norma M. P. Machado¹, Gustavo C. Melo¹, Matheus F. Camargo¹, Giulianna G. Feijó¹, Bruna M. S. Putton², Clarice Steffens², Rogerio L. Cansian², Luiz A. Pessan¹, Francys K. V. Moreira^1,*

Journal of Renewable Materials, Vol.9, No.2, pp. 337-349, 2021, DOI:10.32604/jrm.2021.011081

Abstract Food packaging materials compounded with antimicrobial additives can substantially diminish the incidence of foodborne diseases. Here, poly(L-lactic acid) (PLA) films containing sodium metabisulfite (NaM) were produced by melt extrusion as an attempt to develop a new biodegradable material with antimicrobial properties for packaging. Life cycle assessment (LCA) simulations revealed that the environmental footprints of the PLA film did not change upon NaM addition, and that NaM is more eco-friendly than silver nanoparticles. The PLA/NaM films with NaM content varying from 0.5 to 5.0 wt.% were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and optical and mechanical properties determinations.… More >

J. Y. Tey^*, W. H. Yeo, Y. J. King, W. O. Ding

Journal of Renewable Materials, Vol.8, No.12, pp. 1671-1680, 2020, DOI:10.32604/jrm.2020.011870

Abstract Polylactic acid (PLA) bioplastic is a common material used in Fused Deposition Modeling (FDM) 3D printing. It is biodegradable and environmentally friendly biopolymer which made out of corn. However, it exhibits weak mechanical properties which reduced its usability as a functional prototype in a real-world application. In the present study, two PLA composites are created through coextruded with 3K carbon fibres and twisted Kevlar string (as core fibre) to form a fibre reinforced parts (FRP). The mechanical strength of printed parts was examined using ASTM D638 standard with a strain rate of 1 mm/min. It has been demonstrated that the… More >

Matea Perić^1,*, Robert Putz¹, Christian Paulik²

Journal of Renewable Materials, Vol.8, No.7, pp. 759-772, 2020, DOI:10.32604/jrm.2020.09284

Abstract In the current study poly(lactic acid) PLA composites with a 3 wt% and 5 wt% of nanofibrillated cellulose (NFC) were produced by 3D-printing method. An enzymatic pretreatment coupled with mechanical fibrillation in a twin screw extruder was used to produce high consistency NFC. Scanning electron microscopy (SEM) equipped with Fibermetric software, FASEP fiber length distribution analysis, Furrier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), tensile tests, impact tests and differential scanning calorimetry were used to characterize NFC and PLA/NFC composites. The results of the fiber length and width measurements together with the results of the SEM analysis showed that enzymatic… More >

Mariia Stepanova¹, Ilia Averianov¹, Olga Solomakha¹, Natalia Zabolotnykh², Iosif Gofman¹, Mikhail Serdobintsev², Tatiana Vinogradova², Viktor Korzhikov-Vlakh^1,3, Evgenia Korzhikova-Vlakh^1,3,*

Journal of Renewable Materials, Vol.8, No.4, pp. 383-395, 2020, DOI:10.32604/jrm.2020.09206

Abstract The biocomposite films were prepared from poly(L-lactic acid) and cellulose nanocrystals. To improve interfacial compatibility of hydrophilic cellulose nanocrystals with hydrophobic matrix polymer as well as to provide the osteoconductive properties, cellulose was functionalized with poly(glutamic acid). The modified cellulose nanocrystals were better distributed and less aggregated within the matrix, which was testified by scanning electron, optical and polarized light microscopy. According to mechanical tests, composites filled with nanocrystals modified with PGlu demonstrated higher values of Young’s modulus, elongation at break and tensile strength. Incubation of composite materials in model buffer solutions for 30 weeks followed with staining of Ca²⁺… More >

Michael R. Snowdon^1,2, Amar K. Mohanty^1,2, Manjusri Misra^1,2*

Journal of Renewable Materials, Vol.5, Suppl.1, pp. 94-105, 2017, DOI:10.7569/JRM.2017.634134

Abstract This article assesses the performance of a biobased carbon as a nucleator using common techniques to stimulate poly(lactic acid) crystallization and enhance the thermal stability of PLA during injection molding. The combination of a biodegradable plasticizer, poly(ethylene glycol) (PEG), along with biobased carbon-rich pyrolyzed biomass char residue and an industrially available microcrystalline talc, were tested for nucleating agent capabilities at additions of 10 wt%. Differential scanning calorimetry (DSC) data demonstrated that the inclusion of the plasticizer could increase the PLA crystalline content with further improvements when nucleating agent was present. With a higher mold temperature, the PLA crystallinity surpassed 40%… More >

Ja-Ryong Koo¹, Hye Min Park¹, Se Kyung Kim², Hyun Shik Yun^1,*

Journal of Renewable Materials, Vol.7, No.4, pp. 365-372, 2019, DOI:10.32604/jrm.2019.04170

Abstract Lactic acid is an important organic acid that is widely used in the food, pharmaceutical, and cosmetic industries. Lactic acid was produced from coffee ground waste which contains fermentable sugars and is increasingly generated from our daily dietary life. Among 114 strains of Lactobacillus species, Lactobacillus rhamnosus ATCC 10863 was selected for the production of lactic acid from coffee ground waste. Through alkali pretreatment and saccharification, cellulose and hemicellulose in coffee ground waste were converted into fermentable sugars. Pretreatment experiments were conducted at various alkali solution, concentrations, and times. Alkali pretreatment with 35 g/L of KOH at 121oC for 60… More >

Laura Ribba, Jonathan Cimadoro, Silvia Goyanes^*

Journal of Renewable Materials, Vol.7, No.4, pp. 355-363, 2019, DOI:10.32604/jrm.2019.04083

Abstract In this work, conductive polymer nanocomposites were developed based on a biodegradable and biobased polymer (poly (lactic acid)), with the incorporation of only 0.3 wt% of carbon nanotubes (CNTs) to be used as volatile solvent sensors. The correct dispersion of the nanofiller was achieved thanks to a CNT non-covalent modification with an azo-dye (disperse orange 3) which allowed to reach the percolation for electric conduction in values as low as 0.3 wt%. The chemo-resistive properties of the developed sensors were investigated by exposure to organic vapors (ethanol, tetrahydrofuran and toluene) and water vapor, showing good selectivity. In addition, considering the… More >

Y. Shimamura¹, Y. Shibata², K. Tohgo³, H. Araki⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.3, pp. 189-194, 2008, DOI:10.3970/icces.2008.006.189

Abstract Polylactic acid (PLA) is a biodegradable plastic made from lactic acid, and can be produced by renewable raw materials. The mechanical properties of PLA are, however, not sufficient for structural materials. In our study, carbon nanofiber reinforced PLA was fabricated to overcome the deficiency of PLA and the mechanical properties were measured at room and elevated temperatures. Vapor grown carbon fiber (VGCF) was used for reinforcement. Three point bending specimens were fabricated by using injection molding, and then bending stiffness, bending strength and fracture toughness were measured for amorphous and crystallized specimens. As a result, it is shown that the… More >