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 was low for pure phenolic… More >

M. Asim¹, M. Jawaid^1,4*, K. Abdan², M.R. Ishak³, O.Y. Alothman^4,5

Journal of Renewable Materials, Vol.6, No.1, pp. 38-46, 2018, DOI:10.7569/JRM.2017.634148

Abstract In this study, pineapple leaf fiber (PALF), kenaf fiber (KF) and PALF/KF/phenolic (PF) composites were fabricated and their mechanical properties were investigated. The mechanical properties (tensile, flexural and impact) of the PALF/KF/PF hybrid composites were investigated and compared with PALF/KF composites. The 3P7K exhibited enhanced tensile strength (46.96 MPa) and modulus (6.84 GPa), flexural strength (84.21 MPa) and modulus (5.81 GPa), and impact strength (5.39 kJ/m2) when compared with the PALF/PF and KF/PF composites. Scanning electron microscopy (SEM) was used to observe the fracture surfaces of the tensile testing samples. The microstructure of the 7P3K hybrid composite showed good interfacial… More >

F. J. Santiago-Medina¹, A. Pizzi^{1, 2*}, M. C. Basso¹, L. Delmotte³, S. Abdalla²

Journal of Renewable Materials, Vol.5, No.5, pp. 388-399, 2017, DOI:10.7569/JRM.2017.634142

Abstract The reaction of a desulphurized kraft lignin with hexamethylene diamine as a model of a polyamine has been investigated. For this purpose, guaiacol was also used as a lignin model compound and treated under similar conditions. Solid state CP-MAS 13C NMR, FTIR and MALDI-TOF spectroscopy studies revealed that polycondensation compounds leading to resins were obtained by the reaction of the amines with the phenolic and aliphatic hydroxy groups of lignin. Simultaneously a second reaction leading to the formation of ionic bonds between the same groups occurred. These new reactions have been clearly shown to involve several phenolic and alcohol hydroxyl… More >

Mohamed Ammar¹, Ramzi Khiari^2,3,4*, Mohamed Naceur Belgacem^3,4*, Elimame Elaloui¹

Journal of Renewable Materials, Vol.5, No.2, pp. 116-123, 2017, DOI:10.7569/JRM.2016.634136

Abstract The present study investigated the preparation of biomatrices from Stipa tenacissima L. and its valorization for fiberboard application. Resins were produced by extracting lignin from the Stipa tenacissima L. black liquor by soda process and combining it with glyoxal as crosslinking agent to produce lignin-glyoxal-resin (LGR). The matrix was characterized by several methods, such as FTIR and ATG/ATD, and then mixed with date palm rachis as reinforcing fibers in different proportions of 30 and 50% (w/w with respect to the matrix) to produce biodegradable composite materials. Then, their thermal and mechanical properties were determined, using differential scanning calorimetry (DSC) and… More >

Arunjunairaj Mahendran^1*, Günter Wuzella¹, Thomas Hardt-Stremayr¹, Wolfgang Gindl-Altmutter²

Journal of Renewable Materials, Vol.4, No.3, pp. 215-224, 2016, DOI:10.7569/JRM.2016.634110

Abstract Woven natural fiber-reinforced composites were fabricated using four different flax fabrics and two biobased epoxy resin matrices. The reinforced composites were prepared using resin infusion technique and fiber volume fractions of between 28–35% were achieved using this method. The fiber matrix interaction and the failure mechanism in the composite were observed using scanning electron microscopy. The flexural strength and modulus on the warp and weft directions were characterized and it was found that based on yarn count and yarn thickness change in the flexural strength was observed. Dynamic water absorption and thickness swelling were observed for a certain period of… More >

A. Sammaiah¹, K. V. Padmaja¹, K. I. Suresh^*,2, R. B. N. Prasad¹

Journal of Renewable Materials, Vol.4, No.2, pp. 113-122, 2016, DOI:10.7569/JRM.2015.634118

Abstract This article reports the effect of epoxidized jatropha oil (EJO) on the thermal, cure and viscoelastic properties of epoxy resins. Epoxidized jatropha oil with an oxirane value of 5.0 was prepared and epoxy formulations containing different concentrations of EJO were evaluated for cure, morphology, thermal and viscoelastic properties. The curing temperature of the formulations increased with increasing EJO content. The glass transition temperature of the cured films decreased from 56 °C for unmodified epoxy resin to 23 °C for the sample with 60 wt% EJO reactive diluent, suggesting good plasticizing action. The thermal decomposition was only marginally affected. More >

Flávio Pereira¹, João Pereira², Nádia Paiva³, João Ferra³, Jorge Manuel Martins^1,4, Fernão D. Magalhães¹, and Luísa Carvalho^1,4*

Journal of Renewable Materials, Vol.4, No.1, pp. 41-46, 2016, DOI:10.7569/JRM.2015.634128

Abstract This work studies the use of soy protein as a natural formaldehyde scavenger in wood particleboard production. The protein is incorporated in two forms: a) as a powder, during the blending process of wood particles with urea-formaldehyde binder resin, and b) as an aqueous solution, added at different times during resin synthesis. Analysis of variance (ANOVA) was used to evaluate the signifi cance level of two effects (amount of added soy and time of addition) on internal bond strength, thickness swelling, and formaldehyde content of the resulting panels. The results showed that soy protein can contribute to decrease the formaldehyde… More >

R.H. Haney¹, R.V. Mohan²

CMES-Computer Modeling in Engineering & Sciences, Vol.95, No.5, pp. 431-452, 2013, DOI:10.3970/cmes.2013.095.431

Abstract The use of Graphics Processing Units (GPUs) as co-processors for single CPU/GPU computing systems has become pronounced in high performance computing research, however the solution of truly large scale computationally intensive problems require the utilization of multiple computing nodes. Multiple CPU/GPU computing systems bring new complexities to the observed performance of computationally intensive applications, the more salient of which is the cost of local CPU-GPU host and intra-nodal communication. This paper compares and analyzes the performance of a computationally intensive application represented by resin infusion flow during liquid composite molding process for the manufacture of structural composites application via two… More >

D.S. Liu^1,2, Z.H. Fong¹, I.H. Lin¹, Z.W. Zhuang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.93, No.6, pp. 441-468, 2013, DOI:10.3970/cmes.2013.093.441

Abstract In this study, we proposed a novel numerical technique to simulate the transient moisture diffusion process and to apply it to heterogeneous composite resins. The method is based on a heterogeneous hybrid moisture element (HHME), with properties determined through an equivalent hybrid moisture capacitance/ conductance matrix that was calculated using the conventional finite element formulation in space discretization and the q-method in time discretization, with similar mass/stiffness properties and matrix condensing operations. A coupled HHME with finite element scheme was developed and implemented in the computer code by using the commercial software MATLAB to analyze the transient moisture diffusion process… More >

Duning Li¹, Yufeng Nie^1,2, Xuemei Zhou¹, Li Cai¹

CMES-Computer Modeling in Engineering & Sciences, Vol.72, No.2, pp. 149-166, 2011, DOI:10.3970/cmes.2011.072.149

Abstract In this study, the efficient discrete model including the resin infusion and the fiber compaction is developed to simulate the RFI (resin film infusion) process. The non-linear governing equations are derived by the Darcy's law, the Terzaghi's law and the continuity equations. The finite element method and the finite difference method are used to discretize the proposed equations, and the VOF method is used to track the filling front. Compared with the analytical results of Park, our numerical results agree well with them. Furthermore, we analyze the RFI process of BMI/G0814, and simulate the resin pressure, the fiber volume fraction… More >