Open Access
ARTICLE
A. M. Borrero-López1, F. J. Santiago-Medina1, C. Valencia1,2*, M. E. Eugenio3, R. Martin-Sampedro3, J. M. Franco1,2
Journal of Renewable Materials, Vol.6, No.4, pp. 347-361, 2018, DOI:10.7569/JRM.2017.634160
Abstract It is known that large amounts of residual lignin are generated in the pulp and paper industry. A new alternative for Kraft lignin valorization, which consists of first a chemical modification using a diisocyanate and then the efficient dispersion in castor oil to achieve stable gel-like systems, is proposed in this work. Rheological properties and microstructure of these materials were determined by means of small amplitude oscillatory shear tests and viscous flow measurements and atomic force microscopy observations, respectively. Moreover, both standardized penetration tests and tribological assays, usually performed in the lubricant industry, were carried out to evaluate the performance… More >
Open Access
ARTICLE
Galia Moreno, Karla Ramirez, Marianelly Esquivel, Guillermo Jimenez*
Journal of Renewable Materials, Vol.6, No.4, pp. 362-369, 2018, DOI:10.7569/JRM.2017.634167
Abstract Cellulose, microcrystalline cellulose and nanocellulose were prepared from three agricultural waste resources: pineapple leaf (PALF), banana rachis (BR), and sugarcane bagasse (SCB). Each waste resource was first converted into microcrystalline cellulose which was subsequently converted into cellulose nanoparticles by using mild (30% w/v) and strong (60% w/v) sulfuric acid concentrations for extraction. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to characterize each waste resource and extracted cellulosic materials. Furthermore, nanocelluloses were studied by zeta potential, size analysis, and transmission electron microscopy (TEM). Cellulose nanowhiskers were successfully obtained and isolated with a 33% average… More >
Open Access
ARTICLE
O. Gil-Castell1, J. D. Badia1,2, A. Ribes-Greus1,*
Journal of Renewable Materials, Vol.6, No.4, pp. 370-382, 2018, DOI:10.7569/JRM.2017.634170
Abstract A blending strategy of virgin and reprocessed polylactide may be postulated as an alternative to reduce the material cost at industrial level, and as a valorization route to plastic waste management of production scraps. The performance of blends prepared from virgin polylactide and polylactide mechanically reprocessed up to two cycles (PLA-V/R) was assessed in terms of thermo-oxidative stability, morphology, viscoelasticity and thermal kinetics for energetic valorization. PLA-V/R blends showed appropriate thermo-oxidative stability. The amorphous nature of polylactide was preserved after blending. The viscoelastic properties showed an increment of the mechanical blend effectiveness, which suggested the feasibility of using PLA-V/R blends… More >
Open Access
ARTICLE
M. Asim1, M. Jawaid1,2*, M. Nasir3, N. Saba1
Journal of Renewable Materials, Vol.6, No.4, pp. 383-393, 2018, DOI:10.7569/JRM.2017.634162
Abstract This study deals with the analysis of dynamic mechanical, thermal and flammability properties of treated and untreated pineapple leaf fiber (PALF) and kenaf fiber (KF) phenolic composites. Results indicated that storage modulus was decreased for all composites with increases in temperature and pattern of slopes for all composites, having almost the same values of E' at glass transition temperature (Tg). The peak of the loss modulus of pure phenolic composites was shown to be much less. After the addition of kenaf/PALF, peaks were higher and shifted towards a high temperature. The Tan delta peak height was low for pure phenolic… More >
Open Access
ARTICLE
Ragab E. Abou-Zeid1*, Mohamed A. Diab1, Salah A. A. Mohamed2, Ahmed Salama1, Hind Abdullah Aljohani3, Kamel Rizq Shoueir4
Journal of Renewable Materials, Vol.6, No.4, pp. 394-401, 2018, DOI:10.7569/JRM.2017.634156
Abstract The current article addresses a new strategy for the preparation of polylactic acid/cellulose nanocrystal (PLA/CNCs) nanobiocomposite films with improved structural morphology, mechanical and barrier properties for food packaging applications. The addition of hexadecyltrimethylammonium bromide (CTAB) and sodium lauryl sulfate (SLS) as cationic and anionic surfactants respectively, was found to play a crucial role in preventing re-aggregation of the CNCs during drying and improving the dispersion of CNCs in the PLA. The coated paper was characterized using mechanical tests, water vapor permeability (WVP), X-ray diffraction (XRD), scanning electron microscopy (SEM) and air permeability. The results showed that the paper coated with… More >
Open Access
ARTICLE
Nikolay Dishovsky1*, Petrunka Malinova1, Ivan Uzunov2
Journal of Renewable Materials, Vol.6, No.4, pp. 402-412, 2018, DOI:10.7569/JRM.2017.634171
Abstract Natural products from agricultural wastes are finding importance in the polymer industry due to their many advantages such as being lightweight, low cost and environmentally friendly. In the present study the potential of the two types of rice husk ash (RHA) prepared under different conditions as fillers in natural rubber-based elastomer composites was investigated. The fillers were prepared by rice husks incineration and characterized by means of X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET) specific surface area, Hg-porosimetry and N2-adsorption. The evaluation involved determining the vulcanization characteristics of the compounds and their… More >
Open Access
ARTICLE
F.J. Santiago-Medina1, M.C. Basso1, A. Pizzi1,2,*, L. Delmotte3
Journal of Renewable Materials, Vol.6, No.4, pp. 413-425, 2018, DOI:10.7569/JRM.2017.634172
Abstract The reaction of a desulphurized kraft lignin with hexamethylene diamine and dimethyl carbonate has allowed the development of isocyanate-free polyurethane resins. The present research work is based on previous studies made with hydrolyzable and condensed tannins, but takes advantage of the higher number of hydroxyl groups present in lignin and their different aliphatic and aromatic character. The obtained materials were analyzed by Fourier transform infrared (FTIR) spectroscopy, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and solid-state cross-polarization/magic angle spinning (CP MAS) 13 C nuclear magnetic resonance (NMR), which have revealed the presence of urethane functions. The interpretation of the… More >
Open Access
ARTICLE
S. Michałowski1, M. A. Mosiewicki2*, M. Kuran´ska1, M. I. Aranguren2, A. Prociak1
Journal of Renewable Materials, Vol.6, No.4, pp. 426-437, 2018, DOI:10.7569/JRM.2017.634163
Abstract Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils. The reference material was modified by replacement of the commercial polyol by 10% of biopolyols and also by addition of sisal fibers up to 5 wt%. The higher functionality of the biopolyols increased the crosslinking density of the networks and this was reflected by an increase in hardness and a decrease in water absorption. The effect of the sisal fibers mainly improved the mechanical and thermomechanical properties of the system with rapeseed oil because of good dispersion and strong fiber-matrix interaction.… More >
Open Access
ARTICLE
Kunal Wazarkar, Anagha Sabnis*
Journal of Renewable Materials, Vol.6, No.4, pp. 438-449, 2018, DOI:10.7569/JRM.2017.634159
Abstract The research work presented in this article deals with the synthesis of cardanol-based polyol and its curing with hexabutoxymethyl melamine (HBMM) for application in coatings. Cardanol-based polyol was prepared via thiol-ene click reaction using thioglycerol. Unsaturation present in the long chain of cardanol was successfully utilized to synthesize polyol via thiol-ene coupling. The reaction was carried out between cardanol and thioglycerol in the presence of Irgacure 184 (photoinitiator) and 1,8-Diazabicyclo[5.4.0]undec-7-ene (catalyst) under UV light for 12 h at 80 °C. After completion of the reaction, one mole of thioglycerol was successfully added across the double bond of a fatty chain… More >