Fei Song¹, Puyou Jia^1,*, Yanan Xiao², Caiying Bo¹, Lihong Hu¹, Yonghong Zhou^1,*

Journal of Renewable Materials, Vol.7, No.10, pp. 1011-1021, 2019, DOI:10.32604/jrm.2019.08044

Abstract Phenolic foams (PFs) as thermal insulation material with outstanding flame retardancy are required to match society’s ever expanding safety expectations; however, a trade off exists between flame retardancy and toughness. Here, for the first time, we synthesized a novel reactive phosphorus containing tung oil based derivative and used it to toughen PF, resulting in PFs with a combination of excellent mechanical properties and flame retardancy. Compared with pure PF, the modified PFs exhibit enhanced mechanical properties, with specific compressive and flexural strengths as high as 5.67 MPa and 12.46 MPa, which represent increases of 90.67% More >

Yin Yang¹, Xiaoyan Cao¹, Zhiqiang Wang^1,*, Zhijun Liang¹, Jianhui Zhou^2,*

Journal of Renewable Materials, Vol.7, No.10, pp. 957-965, 2019, DOI:10.32604/jrm.2019.07558

Abstract The out-of-plane shear properties of cross-laminated timber (CLT) substantially influence the overall mechanical properties of CLT. Various testing methods and theories related to these properties have recently been developed. The effects of the number of layers (three and five layers) and testing method (short-span three- and four-point bending tests) on the out-of-plane shear properties of CLT were evaluated. The out-of-plane shear strength values were calculated based on different theories for comparison. The failure mode in the short-span four-point bending (FPB) method was mainly the rolling shear (RS) failure in the cross layers, indicating that the More >

Haitao Li^1,2,*, Zhenyu Qiu², Gang Wu^1,*, Dongdong Wei³, Rodolfo Lorenzo⁴, Conggan Yuan³, Huizhong Zhang^1,2, Rong Liu^1,2

Journal of Renewable Materials, Vol.7, No.7, pp. 583-600, 2019, DOI:10.32604/jrm.2019.07592

Abstract In order to investigate the influence of length and compression directions upon behaviour of parallel bamboo strand lumber (PBSL) specimens, 240 axial compression tests have been performed. With three similar one different typical failure modes, the mechanical performance for PBSL specimens under compression parallel to grain and perpendicular to grain are different as a whole. From the point of the characteristic values, the compression strength parallel to grain is 2.1 times of the compression strength perpendicular to grain. The elastic modulus for compression parallel to grain is 3.64 times of the compression strength perpendicular to… More >

Puyou Jia¹, Fei Song¹, Qiaoguang Li^2,*, Haoyu Xia³, Mei Li^1,*, Xugang Shu², Yonghong Zhou¹

Journal of Renewable Materials, Vol.7, No.7, pp. 601-619, 2019, DOI:10.32604/jrm.2019.07011

Abstract Polymers from renewable resources are receiving tremendous attention due to the increasing concerns on the depletion of fossil oils and deteriorated environments. Cardanol, as an abundant and renewable chemical raw material, has been widely used for the production of renewable polymer materials via converting into various of chemical monomers with active functional groups. This comprehensive review deals with various aspects of cardanol as a starting material the preparing various polymer and polymer composites such as benzoxazine resins, phenolic resin, polyurethanes, epoxy resin, vinyl ester polymers, polyamide and cyanate ester resins. The assessment of the future More >

Abdelkrim Trabelsi^1,*, Zakaria Slimani¹, Akli Younsi², Joseph Virgone¹, Rafik Belarbi²

Journal of Renewable Materials, Vol.7, No.6, pp. 547-556, 2019, DOI:10.32604/jrm.2019.04426

Abstract Water adsorption and capillarity are key phenomena involved during heat and moisture transfer in porous building materials. They account for interaction between solid matrix, liquid water and moist air. They are considered through Water Vapor Adsorption Isotherm (WVAI) and Retention Curve (RC) functions which are constitutive laws characterizing water activity within a porous medium. The objective of this paper is to present a water vapor adsorption and retention models built from multimodal Pore Size Distribution Function (PSDF) and to see how its parameters modify moisture storage for hygroscopic and near saturation ranges. The microstructure of… More >

Aklouche Leila¹, Monteau Jean-Yves², Rezzoug Sid-Ahmed¹, Maugard Thierry³, Guihard Luc², Cohendoz Stephane¹, Maache-Rezzoug Zoulikha^1,*

Journal of Renewable Materials, Vol.7, No.6, pp. 535-546, 2019, DOI:10.32604/jrm.2019.04361

Abstract Specific heat (Cp) and effective thermal conductivity (λ) of native maize starch (NS) were measured by DSC and transient heat transfer method, respectively, at different moisture contents and temperatures. The dependency of temperature (T) and moisture content (W) on the two parameters were investigated. The thermophysical properties of treated starch (TS) by four hydrothermal processes (RP-HMT, IV-HMT, DV-HMT and FV-HMT) were measured and compared to native strach. Hydrothermal treatments were performed at 3 bars (133°C) for 10 min. For Cp and λ measurements, moisture content varied for NS from 5 to 21.5% d.b. and from… More >

Engozogho Anris Starlin Peguy^1,2, Bikoro Bi Athomo Arsene^1,2, Vidal Marcia⁵, Denaud Louis⁴, Safou Tchiama Rodrigue^2,3, Charrier Bertrand¹

Journal of Renewable Materials, Vol.7, No.6, pp. 517-522, 2019, DOI:10.32604/jrm.2019.04051

Abstract In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre (okoume) timber industry, various chemical analysis were carried out on samples from different origins. Total extractives content of the bark, sapwood and heartwood of okoume were evaluated. thermogravimetric analyses were performed and the stiasny number was calculated. it was found that the bark was richer in fatty acid of high molecular weight while the sapwood was rich in fatty acid of low molecular weight. the condensed tannins content varied according to the origin and the part of the tree. More >

Samir Kamel^1,*, Ahmed A. Haroun², Amany M. El-Nahrawy³, Mohamed A. Diab¹

Journal of Renewable Materials, Vol.7, No.2, pp. 193-203, 2019, DOI:10.32604/jrm.2019.00144

Abstract In this work, conducting composites of nanocellulose (NC)/polypyrrole nanoparticles (NPPy) and silver nanoparticles (AgNPs), i.e., NC/NPPyAg, were synthesized for the first time, to the best of our knowledge, via in situ emulsion polymerization of pyrrole in the presence of surfactant dopants. The AgNPs acted as an oxidizing agent to simultaneously incorporate nanoparticles into the prepared composites. The structures and morphologies of the prepared composites were studied using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), UV-Vis Spectra, thermogravimetric analysis (TGA), and scanning and transmission electron microscopy (SEM and TEM) techniques. Additionally, the prepared composites were characterized More >

Hiroshi Okada^*, Tatsuro Ishizaka, Akira Takahashi, Koichiro Arai, Yasunori Yusa

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.1, pp. 10-11, 2019, DOI:10.32604/icces.2019.05037

Abstract In this paper, a new three-dimensional J-integral for non-homogeneous solids undergoing large deformation and associated with residual stresses is presented. The formulation of J-integral involves the strain energy density W that is generally defined by the integral W = ∫₀^t τ_ijε^·_ijdt⁻ over the entire deformation history of a material point where t_ij and ε^·_ij are the components of the Kirchhoff stress and those of velocity strain. t and t represents the time. It is assumed that at t = 0 the body is free from any deformation and therefore the stresses are zeros.
Residual stresses are induced by… More >

Jinxing Liu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.1, pp. 8-8, 2019, DOI:10.32604/icces.2019.04952

Abstract A new method is proposed to simulate progressive failure processes in heterogeneous brittle materials such as concrete, ceramics, rocks etc., by considering the time-dependence of stress redistributions induced by local breakages. Two mechanisms of stress redistribution are incorporated into the proposed model in order to account for the influence of each local breakage on the remaining specimen: (1) One is the immediate release of internal forces in the breaking element, which is assumed to happen within an infinitesimal time when compared with the characteristic time of external loadings. The release of such internal forces is… More >