Lara Greiner^1,*, Philipp Kukla², Sebastian Eibl¹, Manfred Döring³

Journal of Renewable Materials, Vol.10, No.7, pp. 1931-1950, 2022, DOI:10.32604/jrm.2022.019548

Abstract A novel, versatile flame retardant substructure based on phosphorylated salicylic acid (SCP) is described and used in the synthesis of new flame retardants for HexFlow^® RTM6, a high-performance epoxy resin used in resin transfer molding processes as composite matrix. The starting material salicylic acid can be obtained from natural sources. SCP as reactive phosphorus chloride is converted with a novolak, a novolak containing 9, 10-dihydro-9- oxa-10-phospha-phenanthrene-10-oxide (DOPO) substituents or DOPO-hydroquinone to flame retardants with sufficient thermal stability and high char yield. Additionally, these flame retardants are soluble in the resin as well as react into the epoxy network. The determined… More >

Daša Krapež Tomec, Angela Balzano, Jure Žigon, Milan Šernek, Mirko Kariž^*

Journal of Renewable Materials, Vol.10, No.7, pp. 1787-1796, 2022, DOI: 10.32604/jrm.2022.019760

Abstract As additive manufacturing technologies advance, new opportunities are opening up for their application in the furniture industry. Wood remains one of the leading raw materials in the furniture industry; therefore, possible options for combining it with 3D printing have been researched. The bonding of 3D-printed polymer parts with wood or 3D printing with wood-plastic composites is already known, but in our research we attempted to directly 3D print polylactic acid (PLA) on wood surfaces. The effect of printing parameters, as well as the surface preparation of wood on the shear strength of the bond between wood and on-printed material was… More >

Jürgen Kern^1,*, Judy Libra¹, Christian Ammon¹, York Neubauer², Wenceslau Teixeira³

Journal of Renewable Materials, Vol.10, No.7, pp. 1773-1786, 2022, DOI:10.32604/jrm.2022.019608

Abstract The emissions of two greenhouse gases (GHG), carbon dioxide (CO2) and nitrous oxide (N2O), from six substrates with different carbonaceous content were compared in short and long-term incubation experiments. Three natural soils and three artificial chars were mixed with carbon (C) poor soil (Cambisol) to simulate real conditions after application of char to farmland. The natural soils were a Cambisol, an Anthrosol and a Histosol with C contents of 1.3%, 4.4% and 13.2%, respectively. The three chars produced through thermal conversion of wood chips by hydrothermal carbonisation (HTC), fluidized bed gasification and pyrolysis had C contents of 56.9%, 75.4% and… More >

Wenwen Guo^1,2,3, Wei Cai³, Dong Wang¹, Junling Wang⁴, Xiefei Zhu^5,*, Bin Fei^2,*

Journal of Renewable Materials, Vol.10, No.7, pp. 1875-1888, 2022, DOI:10.32604/jrm.2022.018823

Abstract Fabrication of flame retardants from renewable biomass has aroused extensive interest over the past decade. This work reported a synthesis of isosorbide-derived polyphosphonate (PICPP) as an anti-flammable agent for poly (lactic acid) (PLA). The presence of PICPP notably declined the storage modulus of PLA/PICPP owing to the declined molecular weight of PLA catalyzed by the presence of PICPP. PLA and PLA/PICPP thermally degraded in one stage under either air or nitrogen atmosphere. With increasing the amount of PICPP, the onset thermal decomposition temperature of PLA/PICPP was decreased gradually, owing to the earlier decomposition of PICPP. With only 10 wt% of… More >

Tao Zeng^1,3, Lisheng Deng^1,3,*, Jiechao Chen^2,*, Hongyu Huang^1,3, Hanli Zhuang²

Journal of Renewable Materials, Vol.10, No.7, pp. 1845-1858, 2022, DOI:10.32604/jrm.2022.018803

Abstract A numerical study on the conjugated heat-mass transfer of helical hollow fiber membrane tube bank (HFMTB) for seawater desalination was carried out. Physical and mathematical models of fluid flow, temperature and humidity distribution were constructed to investigate the influences of flow type, Reynolds number, and temperature on the conjugated heat-mass transfer performance of hollow fibers in the distillation membrane module. The conjugated heat-mass transfer characteristics of HFMTB were discussed by utilizing the friction coefficient, Nusselt number (Nu), and Sherwood number (Sh). Results demonstrate that a distillation efficiency enhancement of 29% compared to the straight HFMTB has been detected for four-helical… More >

Cuicui Wang¹, Xin Wei¹, Lee M. Smith², Ge Wang¹, Shuangbao Zhang³, Haitao Cheng^1,*

Journal of Renewable Materials, Vol.10, No.7, pp. 1829-1844, 2022, DOI:10.32604/jrm.2022.018782

Abstract In order to investigate the effect of the relative motion of nano CaCO₃ reinforced bamboo pulp fiber (BPF)/HDPE composite components on the mechanical performance, a comparative study was performed. BPF was treated by nano CaCO₃ blending (BM) and impregnation modification (IM) technology. The composites were produced using hot press (HPMP), extrusion (EMP) and injection molding process (IMP). The physical morphology of BPF was similar at different manufacturing processes. Compared to the samples manufactured by HPMP, a decrease in the (specific) flexural strength of BPF/HDPE composites and an increase in those of composites treated by nano CaCO₃ manufactured by EMP and… More >

Wu Jing^1,2,#, Ren Luo^3,#, Sha Ding², Ping Duan^3,4,5,6,7,*

Journal of Renewable Materials, Vol.10, No.7, pp. 1813-1828, 2022, DOI:10.32604/jrm.2022.018771

Abstract In this study, the workability and reaction mechanism of metakaolin (MK) based geopolymer blended with rice husk ash (RHA) and silica fume (SF) was investigated. The prepared samples were subjected to tests including compressive strength and fluidity tests. X-ray diffraction (XRD) and Scanning electron microscope (SEM) were employed to explore the phase composition and microstructure of geopolymers. The molecular bonding information of geopolymer was provided by Fourier transform infrared spectroscopy (FTIR). Meanwhile, the porosity of geopolymer was obtained by Mercury intrusion porosimeter (MIP) analysis. The high-activity RHA obtained after calcination at 600°C was used as a supplementary cementitious material to… More > Graphic Abstract

Omar Salih Omar^*

Journal of Renewable Materials, Vol.10, No.7, pp. 1979-1988, 2022, DOI:10.32604/jrm.2022.018765

Abstract Monolayer MoS₂ has a promising optoelectronics property, with a bandgap in the visible range; the material is a potential candidate for solar cell applications. In this work, we grew MoS₂ monolayers using a low-pressure chemical vapor deposition approach. To produce uniform wafer-scale MoS₂ monolayer films, precursors molybdenum dioxide (MoO₂) and sulfur (S) are utilized. Atomic force microscopy was used to quantify the thickness of the monolayers, and the result was validated by Raman spectroscopy. Transmission electron microscopy (TEM) was used to confirm the crystalline quality of the monolayers, and photoluminescence spectroscopy was used to evaluate their optical properties. We were… More >

Shaochun Ma^1,2,*, Lin Wang¹, Peng Bao^1,*

Journal of Renewable Materials, Vol.10, No.7, pp. 1961-1978, 2022, DOI:10.32604/jrm.2022.018755

Abstract There are a large number of historic buildings which were mainly made of blue-brick masonry in today’s world. However, for the natural and man-made reasons, these historic buildings have been damaged in different degrees. In order to protect historic buildings more scientifically and learn about the preservation state of existing historic buildings, it is necessary to ascertain the material properties of blue brick in historic buildings. The article takes the blue bricks of historical buildings in Kaifeng area of the Central Plains as an example to study. Through the analysis of physical properties, X-ray fluorescence spectroscopy, X-ray diffraction and scanning… More > Graphic Abstract

Daqin Zhang^1,2, Chufeng Yang³, Huayang Ran^1,2, Juanli Wang^1,2,*, Jintao Wan^1,2,*, Yuhu Li^1,2, Pujun Jin^1,2, Daodao Hu^1,2

Journal of Renewable Materials, Vol.10, No.7, pp. 1797-1811, 2022, DOI:10.32604/jrm.2022.018754

Abstract The development of efficient green flame retardants is an important way to realize more sustainable epoxy thermosets and downstream materials. In this work, a monoepoxide is synthesized through O-glycidylation of eugenol, and then reacted with DOPO (9,10-dihydro-9-oxa-10-phosphophenanthrene-10-oxide) to obtain a new bio-based flame retardant, DOPO-GE. DOPO-GE is blended with a bisphenol A epoxy prepolymer exhibiting good compatibility and DDS (4,4′-diaminodiphenylsulfone) is used as the curing agent to afford epoxy thermosets. Although DOPO-GE leads to the reduced glass transition temperature of the thermosets, the storage modulus increases considerably. The DOPO-GE-modified thermosets exhibit the high thermal stability with the onset thermal decomposition… More >