Kunal Wazarkar, Anagha Sabnis*

Journal of Renewable Materials, Vol.6, No.5, pp. 517-528, 2018, DOI:10.7569/JRM.2017.634181

Abstract This research work discloses the preparation of polyurethane coatings from cardanol modified using thiolene chemistry, wherein unsaturated long alkyl chain of cardanol was successfully utilized via thiol-ene click reaction to synthesize polyol. For this purpose, cardanol and thioglycerol was reacted in the presence of Irgacure 184 (photoinitiator) and 1,8-Diazabicyclo[5.4.0]undec-7-ene (catalyst) and exposed to UV light for 12 h at 80 °C. One mole of thioglycerol was successfully added across the double bond of fatty chain of cardanol and confirmed by chemical and spectroscopic analysis. Further, the polyol thus prepared was cured with various polyisocyanates, viz., More >

Maha L. Shrestha^{1, 2,*}, Mihail Ionescu¹, Xianmei Wan¹, Zoran S. Petrović¹

Journal of Renewable Materials, Vol.6, No.5, pp. 504-516, 2018, DOI:10.7569/JRM.2017.634187

Abstract Biobased aromatic-aliphatic polyols were previously synthesized from a thermal thiol-ene reaction of propoxylated cardanol with 2-mercaptoethanol (ME) in the presence of azobisisobutyronitrile (AIBN) as a radical initiator. Cardanol used for this purpose was obtained as a dark-brown liquid (Gardner Color Reference ∼18). The photochemical thiol-ene reaction can also be used to prepare aromatic-aliphatic polyols by employing cardanol. Via the photochemical thiol-ene reaction, 2-mercaptoethanol was added successfully to C=C double bond of cardanol, suggesting that phenolic group may not play an inhibitory role in the radical thiol-ene reaction. However, we preferred to alkoxylate the phenolic hydroxyl 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 More >

A. Atiqah¹, M. Jawaid^1,*, S. M. Sapuan^1,2, M. R. Ishak³

Journal of Renewable Materials, Vol.6, No.5, pp. 477-492, 2018, DOI:10.7569/JRM.2017.634188

Abstract The aim of the present study was to develop sugar palm fiber (SPF) reinforced thermoplastic polyurethane (TPU) composites and to investigate the effects of fiber surface modification by 2% silane treatment and fiber loading (0, 10, 20, 30, 40 and 50 wt%) on the mechanical and thermal properties of the obtained composites. Surface treatment was employed to improve the fiber-matrix interface, which was expected to boost the mechanical strength of the composites, in terms of tensile, flexural and impact properties. Thermal properties were also investigated by thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA)… More >

Min Fan^1,2,3*, Qiaoling Hu⁴

Journal of Renewable Materials, Vol.6, No.5, pp. 457-463, 2018, DOI:10.7569/JRM.2017.634178

Abstract The absorption behavior of chitosan in alkaline solution by freeze-blasting was studied. The influence of alkaline type, concentration, and small molecules was investigated, as well as the different roles of LiOH and NaOH in the absorption. Chitosan reached its maximum absorption rate when LiOH concentration was 4.8 wt% and NaOH 4.0 wt%, respectively. Chitosan showed better absorption capacity in LiOH solution. Urea could improve the absorption when its concentration was more than or equal to 4.0 wt%, and the improvement was greater in NaOH solution. Thiourea showed no obvious effect in LiOH solution, but showed More >

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 More >

Nikolay Dishovsky^1*, 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… More >

Ragab E. Abou-Zeid^1*, 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 More >

M. Asim¹, M. Jawaid^1,2*, 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 More >

O. Gil-Castell¹, J. D. Badia^1,2, A. Ribes-Greus^1,*

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 More >