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In order to prepare highly heat-resistant packaging insulation materials, in this paper, bismaleimide/epoxy resin (BMI/EP55) composites with different contents of BMI were prepared by melt blending BMI into amino tetrafunctional and phenolic epoxy resin (at a ratio of 5:5). The microstructures and thermal and electrical properties of the composites were tested. The electrostatic potential distribution, energy level distribution, and molecular orbitals of BMI were calculated using Gaussian. The results showed that the carbonyl group in BMI is highly electronegative, implying that the carbonyl group has a strong electron trapping ability. The thermal decomposition temperature of the composites gradually increased with the increase of BMI content, and the 20% BMI/EP55 composites had the highest heat-resistance index, along with a glass transition temperature (Tg) of >250 °C. At different test temperatures, with increase in the BMI content, the conductivity of epoxy resin composites showed a tendency to first decrease and then increase, the breakdown field strength showed a tendency to first increase and then decrease, and the dielectric constant was gradually decreased. Two trap centers were present simultaneously in the composites, where the shallow trap energy level is the deepest in 20% BMI/EP composites and the deep trap energy level is the deepest in 10% BMI/EP55 composites. Correspondingly, the 10% BMI/EP55 composite had a slower charge decay rate, while the 20% BMI/EP55 had a faster charge decay rate. In summary, the BMI/EP55 composites with high heat resistance and insulating properties were prepared in this study, which provided ideas for preparing high-temperature packaging insulating materials. [ABSTRACT FROM AUTHOR]

In this study, carbon spheres decorated with nickel nanoparticles (ACS@Ni NPs) were prepared through arginine-assisted hydrothermal treatment, followed by high-temperature carbonization in a nitrogen atmosphere. ACS@Ni NPs displayed uniform size and excellent monodispersity. The specific surface area increased from 9.03 m2/g to 428.69 m2/g after carbonization. The ACS@Ni NPs were employed as adsorbents in dispersive magnetic solid phase extraction (d-MSPE) to extract methylnaphthalene and acenaphthene. The adsorption capacities of ACS@Ni NPs for methylnaphthalene and acenaphthene were 1592.75 μg g−1 and 1652.83 μg g−1, respectively. In addition, ACS@Ni NPs sustained adsorption efficiencies > 90% even after ten reuse times. Coupled with high-performance liquid chromatography-ultraviolet detection technology, under the optimum experimental conditions, the detection limits of methylnaphthalene and acenaphthene were 0.58 and 0.12 ng mL−1. The recoveries of methylnaphthalene and acenaphthene in all samples remained > 95%, with relative standard deviations < 4.5%. The results indicated that ACS@Ni NPs could be applied in environmental pollution treatment and sample preparation. [ABSTRACT FROM AUTHOR]

The article discusses the construction of a protected outdoor enclosure (cold frame) for Spotted Turtles in Central Europe. The enclosure was designed to accommodate ten adult turtles and was built using upcycled materials to save resources. The author outlines the housing conditions for Spotted Turtles and describes the construction process and materials used in detail. The article also highlights the advantages and disadvantages of the enclosure, as well as the author's experiences with the new system over the past two years. [Extracted from the article]

This study investigates the synthesis and characterization of lignin-formaldehyde (LF) and fully biobased lignin-glyoxal (LG) resins as alternatives to the phenol-formaldehyde (PF) adhesive currently used in the manufacturing of plywood and oriented strand boards (OSB). In this process, phenol was entirely replaced by a commercially available kraft-softwood lignin, while formaldehyde was substituted with glyoxal (a biobased dialdehyde) in the LG resins. Additionally, lignin monomers were used as model compounds to better understand the behavior of lignin in LF and LG resins. The reactions of phenol, lignin monomers, and commercial lignin with formaldehyde and glyoxal were investigated through Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy in both solution and solid states. The results confirmed the successful integration of formaldehyde and glyoxal into phenolic structures, leading to the formation of methylene and glyoxylene linkages during resin synthesis. This process created a robust three-dimensional network, as evidenced by 2D 13C–13C correlation solid-state NMR spectra and FT-IR analyses, which are crucial in studying the structural properties of the cured thermoset solid resins that are insoluble in NMR solvents. These findings highlight the innovative potential of lignin as a renewable alternative to petroleum-based phenol and emphasize the practical applications of a fully biobased lignin-glyoxal adhesive in the production of greener, more sustainable, and formaldehyde-free plywood and OSB wood panels commonly used in building construction. [ABSTRACT FROM AUTHOR]

AbstractLignosulfonates (LS) are employed as partial substitution of phenol in phenolic resins; but to increase their reactivity they require an initial hydroxymethylation reaction. Dual-detection size exclusion chromatography (SEC) is here employed for analyzing the evolution of the molar mass distributions (MMDs) along that reaction. The chromatograms were obtained with a UV detector at 254 nm, in series with a differential refractometer (DR). While the DR was assumed to detect the total instantaneous eluent, the UV signal was assumed to detect the aromatic rings of the lignin polymer, but not the low molar mass carbohydrate contaminants. The reactive lignin fraction exhibited a bimodal distribution, with two main components of different average molar masses. Along the reaction, only the reactive lignin fraction increased the molar masses, and the higher molar mass component also exhibited the higher reactivity. Deconvolution procedures were applied to estimate the MMDs of the contaminants, the total lignin, and the reactive lignin components. [ABSTRACT FROM AUTHOR]

We report the enhanced erosive wear resistance of SiC/SiC ceramic matrix composites (CMCs) integrated with a knit fabric via high-temperature crystallization of relatively cost-effective first-generation (amorphous) Si–C–O–Al fibers (AM; short for Tyranno™ AM), desingned for use as a sliding component. A pyrocarbon (PyC) interface was formed via dip coating in liquid phenolic resin, and matrix densification was achieved by hot pressing at 1900 °C for 1 h at 30 MPa. The PyC-coated AM fibers exhibited low tensile strength values at temperatures below 1600 °C, which increased significantly at 1900 °C (2.68 ± 0.74 GPa). The hot-pressed AM-SiC/SiC CMCs exhibited typical quasi-ductile fracture in a three-point bending test. The erosive wear of the CMCs was investigated using a slurry erosion test, and the associated mechanism was clarified by laser-microscopy-based 3D profiling and scanning-electron-microscopy-based microstructural examination. The matrix of the hot-pressed AM-SiC/SiC CMCs was dense (1.99 % porosity), rigidly structured, and hard (27.1 ± 2.91 GPa), enabling the CMCs to outperform conventional SiC/SiC CMCs in terms of slurry erosion resistance. [ABSTRACT FROM AUTHOR]

The primary aim of this research was to repurpose truck tire rubber waste (TTRW) to address significant environmental challenges associated with tire disposal. This was achieved by devulcanizing the waste rubber and transforming it into versatile thermoplastic vulcanizates (TPVs), offering a novel approach to waste valorization. Devulcanized rubber (DR) was first prepared using a mechano-chemical process to break sulfur crosslinks, restoring the rubber's plasticity. Blends of dynamically cured DR and thermoplastic polyester elastomer (COPE) were then developed. Through experimental investigation, phenolic resin at 16 phr was identified as the optimal curing agent, providing the best curing conditions. This formulation resulted in the highest shear viscosity, facilitating the breakup of the vulcanizing DR phase into smaller domains, approximately 0.77 μm in size, which enhanced interfacial adhesion and mechanical properties such as tensile strength and durability. To further improve the DR/COPE blend, maleic anhydride (MA) was incorporated as a compatibilizer at an optimal loading of 5 wt% relative to DR. MA initially formed hydrogen bonds with COPE and subsequently reacted with the diene rubber in DR via free radical and Diels–Alder mechanisms. These interactions improved interfacial adhesion and promoted finer dispersion of DR domains within the COPE matrix, leading to a refined phase morphology with the smallest domain size of 0.29 μm. The result was enhanced rheological and mechanical properties, including increased tensile strength to 9.3 MPa, elongation at break of 135%, hardness (Shore A) of 75, along with greater elasticity and improved solvent resistance. This study demonstrates the potential of using devulcanized truck tire rubber waste to develop high-performance, sustainable materials for various technological applications. [ABSTRACT FROM AUTHOR]

This study aims to enhance the thermal stability and dielectric properties of an epoxy/phenolic resin-type novolac blend by incorporating carbon nanofibers (CNFs). The EP/novolac-CNF composite was created by dispersing a 10% weight fraction of CNFs into the EP/novolac blend. Various analyses were conducted to assess the improvements brought by the addition of CNFs. Differential Thermal Analysis (DTA) and Dielectric Measurements (DM) were employed to determine the Tg values. Thermogravimetric Analysis (TG) and Differential Thermogravimetric Analysis (DTG) were used to evaluate the thermal stability. Results indicated that the inclusion of carbon nanofibers enhanced the thermal stability of the composite, as evidenced by the increased char yield at temperatures exceeding 700℃, reaching 27.08% compared to 8.4% for the EP/novolac blend. Dielectric measurements were conducted across a frequency range of 10² - 107 Hz and a temperature range of 293-463 K. The results revealed a wide dielectric dispersion in all samples, indicating the presence of Debye relaxation and a broad distribution of relaxation times. Eyring's relaxation rate equation was applied to determine the thermodynamic parameters, such as the Gibbs free energy of activation (ΔG) and entropy (ΔS). The results indicated strong intermolecular interactions in all tested samples. The incorporation of carbon nanofibers into the EP/novolac blend led to improvements in thermal stability and dielectric properties. The analysis of various parameters suggests enhanced performance and potential applications of the EP/novolac-CNF composite in relevant fields. [ABSTRACT FROM AUTHOR]

A huge challenge is how to prepare flexible silicone aerogel materials with good flame retardancy, thermal stability, and hydrophobic properties. In this paper, resorcinol–formaldehyde was introduced into the silicone network composed of methyltrimethoxysilane (MTMS), phenyltriethoxysilane (PTES), and dimethyldimethoxysilane (DMDMS). Flexible hybrid aerogels with excellent thermal insulation, flame retardant, and hydrophobic properties were prepared by the sol–gel method and ambient pressure drying (APD), and the preparation process does not require long-term solvent exchange, only about 3 h of soaking and washing of the wet gel. The results show that the prepared phenolic-silicone aerogel has low density (0.093 g/cm3), low thermal conductivity (0.041 W/m·K), high flexibility, and compression fatigue resistance. The phenolic microspheres are bonded to the silicone skeleton to maintain the original flexibility. After 50% compression deformation, it returns to the original size normally, and there is no significant change in the stress of the sample after 50 compression cycles. Compared with pure silicone aerogels, the hybrid aerogels doped with phenolic have better char yield (65.28%) and higher decomposition temperature (609 °C). The hybrid aerogel sample has good flame-retardant properties, which can withstand alcohol lamp burning without being ignited. The micron-sized phenolic beads give the hybrid aerogels better hydrophobic properties, showing a higher static water contact angle (152°). The excellent thermal and mechanical properties mean that the hybrid aerogels prepared in this paper have good application prospects for aerospace, outdoor equipment, and other fields. [ABSTRACT FROM AUTHOR]

• Microplastics (MPs) in air mass from marine transport in the coastal city cannot be neglected. • Rubber and phenol-formaldehyde resin particles are the most common microplastic (MP) types in the coastal city. • MP particles are concentrated in the small particle size segment (20–50 µm). • The number concentration of MPs in the atmosphere is higher during the day than at night. Airborne microplastics (MPs) are important pollutants that have been present in the environment for many years and are characterized by their universality, persistence, and potential toxicity. This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime. Laser direct infrared imaging (LDIR) and polarized light microscopy were used to characterize the physical and chemical properties of MPs, including number concentration, chemical types, shape, and size. Backward trajectories were used to distinguish the air masses from marine and terrestrial transport. Twenty chemical types were detected by LDIR, with rubber (16.7%) and phenol-formaldehyde resin (PFR; 14.8%) being major components. Three main morphological types of MPs were identified, and fragments (78.1%) are the dominant type. MPs in the atmosphere were concentrated in the small particle size segment (20–50 µm). The concentration of MPs in the air mass from marine transport was 14.7 items/m3 – lower than that from terrestrial transport (32.0 items/m3). The number concentration of airborne MPs was negatively correlated with relative humidity. MPs from terrestrial transport were mainly rubber (20.2%), while those from marine transport were mainly PFR (18%). MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass. The number concentration of airborne MPs is higher during the day than at night. These findings could contribute to the development of targeted control measures and methods to reduce MP pollution. [ABSTRACT FROM AUTHOR]

Purpose: The study of microplastics (MPs) in soils is one of the most important contemporary challenges as they negatively influence soil properties and may adsorb heavy metals and pesticides. Recent data show that they can be transported in the terrestrial food chain, endangering human and animal health. In this pilot study, the qualitative–quantitative analysis of microplastics in soils of allotment gardens, which are mainly used for fruit and vegetable production, was done. Also, sources and environmental risks related to microplastics are discussed. Methods: We applied a four-step approach based on standard soil characteristics, density separation of MPs from the soil matrix, stereoscopic microscopy, and Fourier infrared spectrometry (FTIR). Results: In all studied topsoils, high abundance and heterogeneity of microplastics were found. Microplastics like polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), polyurethane (PUR), phenolic resins (PF), and alkyd resins (AR) were identified. Their sources are not only related to human activities on the allotments, but also deposition with wind or water cannot be excluded. Conclusions: We revealed that soil contamination of microplastics in allotment gardens can be a significant environmental problem that has been overlooked in research. Considering the high amount of people who use allotment gardens and the potential environmental risk, soil contamination by microplastics should be monitored. [ABSTRACT FROM AUTHOR]

This study analyzes the technology for creating polymer composite materials reinforced with glass fiber. Particular attention is given to their applications in the aerospace industry, where stringent requirements for strength, corrosion resistance, and specific strength render these materials indispensable. The main components of composite materials and their properties are examined. Phenol-formaldehyde resins, widely utilized as a matrix for fiberglass plastics in rocket and space engineering, are studied in detail. The thermomechanical resistance of composites, a critical factor determining their performance under extreme conditions, is highlighted. A significant part of the study focuses on the production and curing processes of composite materials. Various curing methods are analyzed, with a focus on the effectiveness of infrared radiation. The findings establish that infrared heating significantly enhances the physical and mechanical properties of composites while reducing production time. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced ceramizable phenolic resin composites (CF/CPR) have been widely used in the field of thermal protection materials. However, the industrial application of the CF/CPR is restricted by its easy oxidation failure at oxidizing environment. In this work, a series of Ni-coated carbon fiber reinforced ceramizable composites modified with AlB 2 and SiC were prepared. The thermal stability, phase evolution and anti-oxidation mechanism of the composites were investigated. The flexural strength and residual weight yield of obtained ceramizable composite after 15 min' static ablation at 1400 °C was 62.3 MPa and 84.0 %, increased by 154.2 % and 51.0 % compared to those of the composite without ceramic fillers. The excellent oxidation resistance and high temperature bearing capacity of the composites can be attributed to the synergistic effect of the multiphase ceramic protective layer and catalytic graphitization of the Ni phase. This work may provide great application prospects in thermal protection materials for hypersonic vehicles under harsh environments. [ABSTRACT FROM AUTHOR]

In this paper, alumina-modified wood liquefaction (AL-WP) was prepared by blending nano-alumina (Al2O3) into wood liquefaction phenolic resin (WP) using a co-blending method. Alumina-modified wood liquefaction protofilament fiber (AL-WPF) was obtained by melt-spinning, curing, and thermo-curing processes, which were followed by carbonization to obtain alumina-modified wood liquefaction carbon fiber (AL-WCF). This paper focuses on the enhancement effect of nano-alumina doping on the mechanical properties and heat resistance of wood liquefaction carbon fiber (WCF), explores the evolution of graphite microcrystalline structure during the high-temperature carbonization process, and optimizes the curing conditions of AL-WPF. The results showed that the introduction of Al2O3 significantly improved the mechanical properties and heat resistance of carbon fibers. When 1.5% Al2O3 was doped and carbonized at 1000 °C, the tensile strength of AL-WCF was increased from 33.78 MPa to 95.74 MPa, there was an enhancement of 183%, its residual carbon rate could reach 79.2%, which was better than that of the undoped wood liquefaction (WCF), and it exhibited a more substantial heat-resistant property. In addition, the best curing process for alumina nanoparticle wood liquefiers was obtained by optimizing the curing conditions: hydrochloric acid concentration of 16%, formaldehyde concentration of 18.5%, temperature increase rate of 15 °C/min, holding time of 3 h, and holding temperature of 100 °C. These studies provide a theoretical basis and technical support for developing and applying carbon fibers from alumina-modified wood liquefiers. [ABSTRACT FROM AUTHOR]

Mechanism of sand mold warping was systematically analyzed through experiments and numerical calculations. The results show that the asymmetric thermal stress is the main factor which leads to warping because of the temperature difference in the sand mold during printing. Then, composite powders with silica particle and thermosetting phenolic resin (TSPF) were developed, and they show better warping resistance below 0.15 J/mm2 compared with those of traditional coated sand. In addition, the thermoplastic phenolic resin (TPPF) was added to further reduce the thermal stress due to its cyclic solid-liquid phase change. When the TPPF content reaches 50% or more, the warping of no longer occurs, and warping ratio is reduced by an order of magnitude. However, when the TPPF content is 100%, the sand mold warps in reverse due to the lack of supporting skeleton. This work provides a new way to restrain the warping of casting sand mold. [ABSTRACT FROM AUTHOR]

The preparation of biological phenolic resin (PF) with green recyclable biomaterials instead of phenol is a research hotspot for solving current resource and environmental problems. In this study, on the basis of introducing lignin into the phenolic system, daidzein of a renewable resource with a rigid structure was selected to modify lignin-based phenolic resin (LPF), and the improvement of the mechanical and thermal properties of the modified phenolic resin under different substitution ratios was studied. The friction materials were prepared with a daidzein-modified lignin-based phenolic resin (D-LPF) as the matrix binder, and their effects on the mechanics and friction and wear properties of friction materials were investigated. The results show that when the proportion of daidzein replacing phenol is 12%, the highest Tp can reach 152.4 °C, and the Tg of the modified D-LPF resins is significantly higher than those of PF and LPF. The highest Ts of D-LPF is 203.3 °C, which is also significantly higher than those of PF and LPF (184.7 °C and 174.6 °C, respectively). The maximum carbon residue rate at 800 °C is 64.2% and is greatly improved compared with the 55.1% and 56.7% of PF and LPF. The bending strength and impact strength of D-LPF-matrix friction materials are obviously higher than those of PF- and LPF-matrix friction materials. The specific wear rate of D-LPF-matrix friction materials is 0.70 × 10−4 mm3/Nm, which is obviously lower than those of PF- and LPF-matrix friction materials and shows good applicational prospect as a matrix resin in friction materials. [ABSTRACT FROM AUTHOR]

Waste Tetra Pak containers, from the same brand of milk, were crushed into fibers. They were formed into composites with 40-mesh bamboo fibers with phenolic resin and hot pressed with different parameters. The effects of hot-pressing temperature, hot-pressing time, hot-pressing pressure, phenolic resin amount, and the ratio of Tetra Pak and bamboo on the elastic modulus, static bending strength, internal adhesive bonding strength, and 24 h thickness swelling rate of the composites were investigated by orthogonal testing. The results showed that during the hotpressing process, hot-pressing temperature was the most important factor for the elastic modulus and static bending strength of the composites and the hot-pressing pressure was the most important factor for the 24 h thickness swelling of the composites. Optimal hot-pressing parameters of TP/bamboo composites were a hot-pressing temperature of 180 °C, hotpressing time of 16 min, hot-pressing pressure of 1.0 MPa, phenolic resin amount of 12%, and ratio of Tetra Pak/bamboo of 9:1, in which the least phenolic resin and the most Tetra Pak materials were added. Moreover, the elastic modulus was 7670 MPa, the bending strength was 40 MPa, the internal adhesive bonding strength was 0.86 MPa, and 24 h thickness swelling rate was 10.6%, meeting the requirements for MDF in different states. [ABSTRACT FROM AUTHOR]

In ZL205A alloy fully enveloped castings, linear segregation has been observed to be a common fault that can cause significant harm to the mechanical properties of the castings. Numerical simulation and similar molding approaches were used to obtain fully enveloped low-pressure castings of ZL205A alloy with linear segregation. Using energy dispersive spectroscopy and scanning electron microscopy, the microstructure of the alloy was examined with the goal to look into the formation mechanism of linear segregation. Results show that when the pressurization pressure P3 = 2P2, the hindered factor ε = 0.129, and the sand core is a phenolic resin sand core, linear segregation takes place in fully enveloped low-pressure castings. In addition, the hindered factor of fully enveloped castings is related to the collapsibility of the sand core, the easier the sand core collapses, the higher the hindered factor. There is a significant risk of hot tearing in localized castings connected to the slit gating system. Melt with a high concentration of Cu in the slit gating to feed hot tearing under pressurization pressure. Linear segregation is formed, and the segregation phase is Al2Cu. [ABSTRACT FROM AUTHOR]

Sinapine adsorption was studied on four weak cation exchanges at pHs ranging from 2 to 8. The best adsorption rate was observed with C106 resin at pH 4 (95.25%). The adsorption kinetics followed a pseudo-second-order model while the isotherm data better fitted the Langmuir model. The ΔG°, ΔH°, and ΔS° values (−25.834 kJ·mol−1, −24.428 kJ·mol−1, and 0.004 kJ·mol−1·K−1) revealed that the adsorption process was spontaneous and exothermic. Acidified ethanol showed a better desorption rate (75.41%), while virtually no (3.32%) or low (31.14%) sinapine desorption was observed with 50% ethanol and 0.1 M HCl solution, respectively. This indicated that sinapine adsorption took place throughout both ionic and hydrophobic interactions. Very close sinapine adsorption performances were observed with an effluent of the patented rapeseed protein isolate process. Two-step desorption using 50% ethanol, then acidified ethanol, yielded a highly purified neutral sinapine-derivative phenol fraction (75.23%) in the first elution fraction and sinapine (98.85%) in the second one. [ABSTRACT FROM AUTHOR]

The rise in environmental and health concerns has led to increasing attention to nature‐derived materials. Natural resin (NR) is secreted by pine trees, and it is a great monomer source for synthesizing biopolymers. The objective of this study is to produce terpene rosin phenolic resin (TRPR) from NR, turpentine, and phenol by applying a novel polymerization technique. An environmentally friendly and reusable catalyst (Amberlyst15) was chosen instead of traditional ones. TRPR samples were chemically characterized using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), and gel permeation chromatography (GPC) analysis. The average molecular weight (Mw) of TRPR was detected as 560 g/mol. Artificial neural network (ANN) modeling was designed with three inputs (pressure, temperature, and terpene/NR ratio) and four outputs (reaction yield, acid value, saponification value, and softening point). The highest TRPR yield was obtained with a terpene/NR ratio of (1/2) at 80°C and under 3 atm. The lowest acid and saponification values were calculated as 90.54 and 100.11 mg KOH/g, respectively. The softening point of TRPR reached 80°C and it was suggested for use in the paper, ink, and adhesive industries. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increasing shortage of energy reserves, the exploration of new energy sources is a growing area of research. As a widely used energy storage device, supercapacitors have attracted widespread attention from researchers. In our study, N- and B-modified phenolic foam was prepared by polymerization using phenol and paraformaldehyde as raw materials, urea and 4-formylphenylboronic acid as modifiers of nitrogen and boron, respectively, and adding foaming agent and curing agent. Modified reduced graphene oxide was synthesized by modifying reduced graphene oxide with nickel and cobalt. Finally, modified reduced graphene oxide-doped phenolic resin-based carbon foams were prepared by mixing and carbonizing the above two modified materials. The effects of mass ratio of Ni to Co, carbonization temperature, and different addition amount of activator on the structure and electrochemical properties of the obtained carbon foam materials were studied. The results show that the specific surface area of the carbonized material can reach 744 m2/g and the pore volume of the material is 0.496 cm3/g when the mass ratio of Ni metal to Co metal salt is 1:1, the mass ratio of activator to modified phenolic foam is 5, and the carbonization temperature is 800°C. And its maximum specific capacitance can reach 1288 F/g at a current density of 1 A/g. When the current density is increased to 10 A/g, its specific capacitance is still maintained at 700 F/g. The electrode has a 65% capacitance retention rate after 1000 cycles. The preparation of carbon foam electrode materials based on phenolic resin provides a theoretical basis for the development of energy storage containers with low cost and high performance. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] Hard carbon is recognized as one of the most promising anode materials for sodium-ion batteries due to its high specific capacity and low cost. Enhancing the closed-pore structure, pseudo-graphite structure, and defects in hard carbon represents an effective strategy for improving the performance of hard carbon anodes. Thermosetting phenolic resin is considered one of the most promising precursors for hard carbon materials, owing to its multifunctional and tunable microstructure. In this study, hard carbon is designed to have a high proportion of pseudo-graphite structure and closed pores at the molecular level. It is found that urea promotes the formation of sp3-hybridized carbon and defects. The microcrystalline structure of hard carbon can be precisely tuned by controlling the sp3C/sp2C ratio. This evolution involves the formation of long-range ordered graphite-like structures, short-range pseudo-graphite structures, and ultimately an amorphous structure with a cross-linked graphite. A successful relationship is established between the evolution of the hard carbon microstructure and the formation of closed pores. The optimized HCUP-40 hard carbon material exhibits a high initial coulombic efficiency of 94.44 % at a current density of 0.1 A g-1, a reversible specific capacity of 418.90 mAh g-1, and excellent cycle stability, maintaining 184.80 mAh g-1 after 1000 cycles at a current density of 5 A g-1. This study provides valuable insights into the regulation of hard carbon microstructure and the design of high-capacity anode materials. [ABSTRACT FROM AUTHOR]

With increasing environmental problems, interest in natural polymers that have less toxic effects on the environment and are biodegradable is increasing day by day. Natural resin is a promising and valuable renewable non-wood forest product and is used as a natural resource in the production of many biochemical products. In this study, it is aimed to synthesize terpene-rosin phenolic resin (TRFR) from crude wood resin, turpentine and phenol in the presence of AlCl3 with an innovative polymerization technique. Before proceeding to the synthesis stage, the raw resin was separated into turpentine and rosin by distillation and characterized with a gas chromatography - mass spectroscopy (GC-MS) device. The synthesized TRFR samples were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance Spectroscopy (NMR), acid number, saponification number and softening point analyses. Moreover, the modeling of synthesis reactions Artificial Neural Network (ANN) was designed with 2 inputs (temperature and turpentine/crude wood resin ratio) and 4 outputs (reaction yield, acid value, saponification value and softening point). The highest reaction efficiency was found in the sample produced at 60°C with a turpentine/crude wood resin ratio of 1/2. The lowest acidity and saponification values were calculated as 90.79 and 103.79 mg KOH/g, respectively. The highest softening point was found to be 79°C.

Yolk–shell structured Sn@C materials are promising candidates of anode materials for lithium-ion batteries due to their high structural stability along cycling. However, their synthesis usually suffers from complicated procedures, low efficiency and uncontrolled morphology and size. In this study, a novel yolk–shell structured composite of phenolic-resin-based Sn@hollow carbon (C) composite was effectively synthesized using tributyl(ethenyl)stannane as the tin source and hexadecyltrimethylammonium bromide as the structure-directing agent. Small Sn particles, with diameters of 10–20nm, were discovered to be encapsulated within hollow carbon spheres of about 100nm and exhibited high dispersion. Benefiting from this excellent structural design, the specific lithium-storage capacity of this composite can still retain a value of 640mAh g−1 after 150 cycles at 0.1A g−1. An excellent rate performance of 280mAh g−1 was achieved at a high current density of 1A g−1, without decay after 600 cycles. The present study highlights the superiority of yolk–shell structure and provides a viable option for synthesizing advanced Sn-based anode materials of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Despite a lot of efforts devoted to construct efficient microbiomes, there are still major obstacles to moving from the lab to industrial applications due to the inapplicability of existing technologies or limited understanding of microbiome variation regularity. Here we show a domestication strategy to cultivate an effciient and resilient functional microbiome for addressing phenolic wastewater challenges, which involves directional domestication in shaker, laboratory water test in small-scale, gas test in pilot scale, water test in pilot scale, and engineering application in industrial scale. The domestication process includes the transition from water to gas, which provided complex transient environment for screening of a more adaptable and robust microbiome, thereby mitigating the performance disparities encountered when transitioning from laboratory experimentation to industrial engineering applications. Within the domestication and application processes for treating phenolic resin wastewater, a powerful functional microbiome was built by self-assembly. This leads to an augmented biodiversity and the development of more intricate phenol and formaldehyde metabolic pathways. The incorporation of increased stochastic processes and random network characteristics further suggested the stability of the microbial community during the application phase. This study elucidates the self-assembly process of microbial communities during the artificial construction process, showcasing their adaptive evolution under different adverse conditions. It serves as a noteworthy case study for the artificial construction of a microbiome for the engineering application of treating industrial wastewater. A domestication strategy to cultivate efficient and resilient functional microbiome for addressing phenolic wastewater challenges sheds light on the artificial construction of microbiome for the engineering application of treating industrial wastewater. [ABSTRACT FROM AUTHOR]

AbstractCarbon fiber/phenolic resin composites (CF/Ph) are often used on the surface of hypersonic vehicles as thermal protection materials. In this paper, the composite materials were prepared by a compression molding process with carbon fiber and boron phenolic resin modified by TiC and B4C. The high-temperature flexural strength and anti-ablation behavior of the composites (TB) were studied. The results showed that the residual weight yield at 1500 °C of TB-10 (B4C content of 10 phr) increased by 39.22% compared to that with no B4C (TB-0). The flexural strength of TB-10 was increased by 19.51% and 19.69% at 1400 °C and 1600 °C, respectively, with respect to TB-0 at the same temperatures. The linear ablation rate and mass ablation rate of TB-10 were reduced by 24.32% and 5.58%, respectively, compared with TB-0. By exploring the anti-ablative mechanisms, it was revealed that PyC, liquid B2O3 and TiO2, all of which were formed at high temperatures, tended to fill the inner cracks of the composite and, therefore, prevent the oxide to further diffuse in. Along with the outer ceramic layer, the three components above play a synergistic effect to improve the ablative property. [ABSTRACT FROM AUTHOR]

Combining the advantages of both containing-B compounds and containing-Ti compounds, a new TiB 2 addition is proposed in MgO-C refractories. In this paper, the high-temperature oxidation behavior of low-carbon MgO-C refractories with TiB 2 addition was investigated, especially the effect of microstructure and phase evolution on the high-temperature oxidation behavior was discussed. The results show that in the materials, TiB 2 preferentially reacts with oxygen, forming TiC x N 1-x , Mg 3 (BO 3) 2 and Mg 2 TiO 4 ceramic phases, and catalyzing the decomposition of phenolic resin to form bamboo-like nanotubes and carbon nanospheres to bond aggregates and fill pores. Meanwhile, TiB 2 also promotes the formation of regenerated MgO compact zone, hindering the diffusion of oxygen into the materials to improve the oxidation resistance. Compared with the blank control specimen and the specimen with B 4 C addition, the oxidation resistance increased by 243.4 % and 79.2 %, respectively. [ABSTRACT FROM AUTHOR]

The inherent susceptibility to oxidation limits the application of carbon fibre/phenolic resin composites (CF/Ph) in the thermal protection of hypersonic vehicle engines. Herein, TiB 2 -B 4 C modified Al-coated carbon fibre/boron phenolic resin ceramizable composites were fabricated. The optimal ceramizable composite (T 30 C 10) exhibited excellent ablation resistance and high-temperature insulation capacity at a linear ablation rate and bottom-surface temperature of −0.00768 mm/s and 129.8 °C, respectively. Oxygen consumption and inhibition, carbon fixation, and self-healing effects contributed to the excellent ablation resistance, and the effects of the Al coatings and carbothermal reduction reactions led to excellent high-temperature insulation capacities. [Display omitted] [ABSTRACT FROM AUTHOR]

In order to enhance the survivability of fighter aircraft, it is crucial to develop microwave absorbing (MA) materials with a low dielectric-temperature dependence. Reduced graphene oxide (RGO) has potential for military stealth applications, but its wave absorbing properties are highly sensitive to temperature fluctuations due to significant conductivity loss. In this work, conductivity and polarization loss are balanced through microstructural design to disrupt the conductive pathways by creating holes on the graphene surface. The holey RGO aerogel/phenolic resin (HRGA/PF) composites with a hierarchical pore structure were synthesized through combining freeze-drying and PF infiltration. The results show that the HRGA/PF composites possess excellent X-band full frequency absorption performance in the temperature range of 25 °C–250 °C, and the reflection loss (RL) is optimized to −62.78 dB. This work expands feasible thoughts for the design of stable MA materials with wide temperature range. [ABSTRACT FROM AUTHOR]

Benefiting from the synergistic effect of holey structures and carbon coating, the hG 0.01 @C 0.10 derived from waste graphite of used lithium-ion batteries displays excellent lithium storage properties. [Display omitted] • The NaOH was used for the separation and purification of waste graphite from used lithium-ion batteries and the creation of holey structures within waste graphite (hG). • The carbon coating by the annealing of phenolic resin enables hG 0.01 @C 0.10 with enhanced electrode kinetic and alleviated volume change during the cycles. • Benefiting from the synergistic effect of holey structures and carbon coating, the hG 0.01 @C 0.10 as anode for LIBs displays excellent lithium storage properties. The efficient recycling of waste graphite anode from used lithium-ion batteries (LIBs) has attracted considerable concerns mainly owing to the environment protection and reutilization of resources. Herein, we reported a rational and facile strategy for the synthesis of holey graphite coated by carbon (hG 0.01 @C 0.10) through the separation, purification and creation of holey structures of waste graphite by using NaOH and carbon-coating by using phenolic resin. The holey structures facilitate the hG 0.01 @C 0.10 with the quick penetration of electrolytes and rapid diffusion of Li+. The carbon coating is more favorable for hG 0.01 @C 0.10 with improved electronic conductivity and less alleviated volume during the cycles. Benefiting from the synergistic effect of holey structures and carbon coating, the hG 0.01 @C 0.10 as anode for LIBs displays a high reversible capacity of 377.6 mAh g-1 at 0.5 C and superior rate capabilities (e.g., 348.0 and 274.7 mAh g-1 at 1 and 2 C, respectively) and maintains a high reversible capacity of 278.7 mAh g-1 at 1 C after 300 cycles with an initial capacity retention of 80.0 %. [ABSTRACT FROM AUTHOR]

Distiller's spent grain (DSG) is a byproduct generated in large quantities during the mashing process, particularly in the production of alcoholic beverages such as whiskey. This study aimed to characterize DSG from nine different distilleries as a potential biorefinery feedstock for the synthesis of high-value bioproducts. Key components, including protein (12.38–26.32%), cellulose (11.75–32.75%), hemicellulose (6.97–19.47%), lignin (8.44–15.71%), and total phenolics (1.42 to 3.97 mg GAE/g), were analyzed to evaluate their variability and suitability for industrial applications. The results reveal that DSG composition varies significantly across distilleries due to differences in processing techniques, even though the starting grain composition had minimal influence. Statistical analysis highlighted the variability of water- and ethanol-soluble extractives (17.34–31.77%) and their potential impact on product consistency. This compositional variability highlights the importance of understanding DSG's structural properties to optimize its use as a lignocellulosic biomass feedstock. This study emphasizes the potential for utilizing DSG in the production of nanocellulose, bioplastics, phenolic resins, and other sustainable materials, thereby contributing to the circular economy. By linking compositional insights to specific applications, this work establishes a foundation for tailored utilization of DSG in biopolymer production and chemical synthesis. These findings provide valuable insights for biorefinery operations, addressing both sustainability challenges and the economic potential of industrial byproducts. [ABSTRACT FROM AUTHOR]

It is essential for the development of highly efficient polymeric photocatalysts for hydrogen peroxide (H2O2) production. Nevertheless, the non‐uniform molecular structures and sluggish reaction pathway of polymeric photocatalysts lead to low conversion efficiency. In this work, we report sulfur‐contained phenolic resins with regulated conjugation for photocatalytic H2O2 production. Due to the substitution of sulfur for methylene in the phenolic resin structure, the conjugation degree of the material is adjusted, resulting in the formation of a built‐in electric field. This effectively enhances the charge separation capability, enabling charge carriers to react faster with substrates. Through in situ characterization and theoretical calculations, we have unveiled that the introduction of sulfur can modulate the reaction pathway of phenolic resin materials, enabling a dual‐pathway photocatalytic H2O2 production mediated by non‐radical species. Impressively, the sulfur‐contained resin photocatalyst showcases exceptional H2O2 production activity with a solar‐to‐chemical conversion efficiency of 1.4 % exceeding most reported systems, and generates 25 mmol m−2 of H2O2 under natural sunlight through large‐scale equipment. This work provides a facile strategy to separate the photogenerated electron–hole pairs of polymer photocatalysts to achieve efficient artificial photosynthesis. [ABSTRACT FROM AUTHOR]

The study investigates the characterization and toxicity of two types of phenolic foams: Floral (FF) and Hydroponic (HF), used in floral arrangements and hydroponic structures. These foams contain a resin with a free phenol content ranging between 5.0% and 8.0%, a substance harmful to plant development and ecosystem contamination. Methods such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy‐energy dispersive spectroscopy (SEM‐EDS), and gas chromatography‐tandem mass spectrometry (GC‐MS/MS) are used for characterization. Acute exposure ecotoxicological tests are conducted with Daphnia magna for the FF sample and lettuce seeds (Lactuca sativa) for both FF and HF samples. Results reveal structural similarities between the foams and phenolic resin, including the presence of residual free phenol at concentrations of 180 ppm in FF and 73 ppm in HF, and possibly different additive treatments between samples. The FF sample had a half maximal effective concentration (EC50, 48 h) = 15.4 ± 2.7 g L−1 for D. magna. Surprisingly, the HF sample proves more toxic to L. sativa than FF, suggesting a potential influence of additives released from the sample's composition beyond the free phenol. This study shows that improper phenolic foam disposal can harm both aquatic and land ecosystems. [ABSTRACT FROM AUTHOR]

In light of the significant impact of climate change, it is imperative to identify effective solutions to reduce the environmental burdens of industrial production and to promote recycling strategies also for thermosetting polymers. In this work, the mechanical recycling of phenolic resins, obtained from industrial production scrap of plastic knobs for household appliances, was optimized. The feasibility of a partial substitution of virgin materials with recycled ones was investigated both at a laboratory and industrial scale. Finally, the environmental benefits arising from the use of recycled material were quantified through a life cycle assessment (LCA). The results of laboratory characterization demonstrated that the thermal properties of the phenolic resins were not influenced by the presence of recycled material, and the mechanical performances were not significantly impaired up to a recycled content of 30 wt%. The industrial production trials demonstrated the feasibility of replacing up to 15 wt% of virgin material without any influence on the aesthetical features of the produced components. Finally, LCA of industrially produced knobs highlighted a limited benefit of virgin material substitution in the case of novolac chromium-plated samples, while an overall environmental impact reduction of around 7–10% was detected in the case of resol-based materials. [ABSTRACT FROM AUTHOR]

This study investigates the development of biomimetic sound-absorbing components through laser sintering technology, drawing inspiration from wood's natural porous structure. Using a pine wood powder/phenolic resin composite, various specimens were fabricated with different structural configurations (solid, fully porous, and varying straight-pore ratios) and cavity thicknesses. Sound absorption performance was evaluated using the impedance tube transfer function method. The effect of different composite structures, placement orientations, and cavity thicknesses on sound absorption performance was evaluated. The results demonstrate that solid laser-sintered samples exhibit inherent sound absorption properties due to microscopic pores, with absorption coefficients exceeding 0.234. The biomimetic wood-like structure, featuring multi-scale porosity at both microscopic and mesoscopic levels, shows enhanced broadband sound absorption, particularly in mid-high frequencies, with characteristic double-peak absorption curves. The study reveals that absorption performance can be optimized by adjusting structural parameters and thickness, enabling targeted frequency-specific sound absorption. This research establishes the feasibility of creating multi-frequency sound-absorbing materials using laser-sintered biomimetic wood structures, providing a foundation for future applications and development in acoustic engineering. [ABSTRACT FROM AUTHOR]

The thermoplastic high-ortho phenolic resins (HPRs) were synthesized by a one-step synthesis using phenol, formaldehyde, zinc acetate, sulfuric acid, and small amounts of ethanol. It was then blended with epoxy resins, and a small amount of ethylenediamine (EDA) was added as a curing agent for dry spinning to produce the as-spun fibers. Heat curing and microwave curing treatments were performed to obtain phenolic epoxy fibers. Using Fourier transform infrared spectroscopy to study the structural changes during the fiber curing process revealed that the amino groups in EDA opened the epoxy groups to generate the hydroxyl groups. The hydroxyl groups can further react with the epoxy groups, which accelerate the curing reaction. Thermogravimetric analysis (TGA) results showed a higher residual carbon degree in the fibers after curing. Mechanical property testing demonstrated a significant improvement in the mechanical properties of the fibers. By modifying the blending and optimizing the curing process, the heat resistance of the fibers was successfully improved, resolving the issue of poor mechanical properties in the high-ortho phenolic epoxy fibers (HPEFs). [ABSTRACT FROM AUTHOR]

Silicon holds great potential as anode material for next-generation advanced lithium-ion batteries (LIBs) due to its exceptional capacity. However, its low conductivity and huge volume changes during charge/discharge process result in a poor electrochemical performance of silicon anode. This study introduces a cost-effective strategy to repurpose KL Si waste from photovoltaic industry into feedstock for LIBs. A Si@C composite with core–shell structure was synthesized from kerf loss (KL) Si waste as the primary capacity contributing ingredient. The nanoscale Si particles (Si NPs) was produced through ball milling and acid pickling of KL Si waste, and then coated a carbon shell by the pyrolyzed phenolic resin. This core–shell structure enhances the electrical conductivity of silicon-based anode, facilitates ion/electron movement, and reduces volume fluctuations of silicon during lithiation/de-lithiation process. Compared to the pure Si anode, the Li+ transmission efficiency of the Si@C anode was significantly improved, leading to a better cycle and rate performance. The resulting SP-2 electrode demonstrated a consistent capacity of 602 mAh g−1 after 150 cycles under current density of 0.5 A g−1. [ABSTRACT FROM AUTHOR]

In the last several decades, there has been significant growth in research and development activities in nanomaterials. Nanotech has been used to improve the quality of several materials, including wood and polymer composites, for their application in various fields. Nanofillers, including metal particles, nano oxides, pyrogenic silica, and carbon black, have been employed as polymer additives. However, the value of natural, low-cost, and plentiful clay materials such as nanoclay becomes more apparent as environmental regulations and consumer awareness become more rigorous. This literature outlines the role of nanoclay on polymer composites, especially in the case of thermosetting resins, including epoxy, polyester, urea-formaldehyde, and phenol-formaldehyde resins. The current article is intended to provide a comprehensive source of recent studies and literature on nanoclay as filler, its classification, polymer modification processes using nanoclay, and comparing the performance of different thermosetting polymers based on their fabrication methods through physical and mechanical properties. [ABSTRACT FROM AUTHOR]

This work presents the results of research on the influence of the amount of p-toluenesulfonic acid and phosphoric acid (V) added to the phenol-formaldehyde resin (pH 7.3–7.8) on its thermal properties and on the phenol-formaldehyde-carbon composite produced on its basis. This material undergoes pyrolysis under high temperature. The addition of a catalyst to the phenol-formaldehyde resin affects its curing rate and degree of cross-linking, but how it affects the thermal properties of the resin depending on the temperature is the subject of this work. This article presents the results of thermal tests for phenol-formaldehyde resin and phenol-formaldehyde-carbon composite. It was examined how the content of the catalyst used during the production process affects the individual thermal parameters of the mentioned materials. The results include experimental tests of thermal diffusivity with uncertainty (±3%), specific heat capacity (±2.5%), thermal expansion with resolution 2 nm analyzed in the temperature range −40–115 °C and thermogravimetric TG/DTA analysis with resolution 0.03 µg in the temperature range from room temperature (RT = 23 °C) to 550 °C. Individual thermal tests showed changes in the thermal properties caused by changes in the catalyst content of the tested materials and the influence of the addition of carbon fibers on the properties of the composite compared to the pure phenol-formaldehyde resin. It was found that there is a certain maximum level of catalyst weight fraction at which the greatest decrease in thermal diffusivity occurs. In the case of phenolic-formaldehyde-carbon composite at −40 °C, an increase in catalyst weight fraction from 2 to 4 wt% caused a decrease in thermal diffusivity by 18.2%, and for phenol-formaldehyde resin, it was 2.8% with an increase in catalyst fraction from 4 to 10 wt%. [ABSTRACT FROM AUTHOR]

This study investigated the influence of preformed composition and pore size on the microstructure and properties of SiCf/SiC composites fabricated via reactive melt infiltration (RMI). The process began with the impregnation of SiC fiber cloth with phenolic resin, followed by lamination and pyrolysis. Subsequent steps included further impregnations with phenolic resin, SiC slurry, and carbon black slurry, each followed by additional pyrolysis. This process resulted in three types of preforms, designated as PP, PS, and PC. These preforms exhibited a multimodal distribution of pore size, with peak pore diameters around 5 μm for PP, ranging from 200 nm to 4 μm for PS, and approximately 150 nm for PC. The preforms were then subjected to molten silicon infiltration at 1600 °C under vacuum for 1 h to create SiCf/SiC composites. The PP preform contained only pyrolytic carbon, leading to a composite with high closed porosity and unreacted carbon, resulting in poor mechanical properties. The PS preform, which was impregnated with SiC particles, displayed an optimized pore size distribution but retained significant amounts of residual silicon and carbon in the final composite. In contrast, the PC preform featured both an ideal pore size distribution and an adequate amount of carbon, achieving high density and low porosity with reduced residual phases in the final composite. This optimization led to a flexural strength of 152.4 ± 15.4 MPa, an elastic modulus of about 181.1 ± 0.1 GPa, and a thermal conductivity of 27.7 W/mK in the SiCf/SiC composites product. These findings underscore the importance of preform optimization in enhancing the performance of SiCf/SiC composites, potentially paving the way for more reliable nuclear fuel cladding solutions. [ABSTRACT FROM AUTHOR]

Cost-effective decarbonization and structural strengthening of carbon-containing refractory materials are crucial for the development of low-carbon steel (LCS) and ultra-low-carbon steel (ULCS) technologies. In this study, a carbonaceous-ceramic reinforcement assembly structure composed of multilayer graphenes and silicon carbide whiskers/particles (MLGs-SiC w /SiC p) has been successfully designed and fabricated. By employing three-roll milling (TRM) for low-cost exfoliation of expanded graphite (EG) into MLGs in a phenolic resin (PF) medium, we optimized the exfoliation cycles to fine-tune the morphology of MLGs. Subsequently, the catalytical solid-state conversion of PF/MLGs reacting with Si into SiC w /SiC p at 1400 °C, under varying C/Si molar ratios and catalyst contents, not only retained the structural integrity of MLGs but also embedded them within a novel SiC w /SiC p composite matrix. Our research elucidates the catalytic conversion mechanism, underscoring the significant role of nickel catalysts in promoting efficient SiC conversion. This work offers a promising pathway for developing high-performance, economical, low-carbon refractories. [ABSTRACT FROM AUTHOR]

In this study, moso bamboo and bamboo scrimber were regarded as the research objects, and their pyrolysis products were qualitatively analyzed by PY-GC/MS. The difference of volatile gas escaped between moso bamboo and bamboo scrimber was also investigated. The results showed that phenolic products, aldehydes-ketones products, furan products, ester products, alcohol products and acid products were detected during the pyrolysis of moso bamboo and bamboo scrimber. In the pyrolysis products, the GC content of phenolic products was significantly different between moso bamboo and bamboo scrimber. The GC content of phenolic substances in moso bamboo was 8.23%, while the GC content of phenolic substances in recombinant bamboo was as high as 26.36%. The GC content of aldehyde-ketone products and furan products from pyrolysis of moso bamboo was higher than that of bamboo scrimber. There was no significant difference in GC content of alcohol ester products between moso bamboo and bamboo scrimber. The GC content of acid products of bamboo scrimber was higher than that of moso bamboo. In addition, the pyrolysis of phenolic resin in bamboo scrimber accelerated the pyrolysis process of bamboo in it. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ablative materials are widely employed to protect space vehicles from the extreme thermal conditions experienced during their flight into a planetary atmosphere. Carbon-phenolic ablators are composed of a phenolic matrix and a fibrous carbon reinforcement. In the present study, the fibrous reinforcement has been modified through the deposition of thin protective layers of zirconium oxide and aluminum oxide, with the objective of reducing fiber recession and oxidation. The depositions were carried out via atomic layer deposition (ALD), a method that allows for the controlled deposition of uniform and conformal coatings on the carbon felt fibers. The depositions were subsequently evaluated through SEM-EDS analysis. Pristine and ALD-modified felts were impregnated with a phenolic resin matrix and the ablation performance of the composite materials was evaluated through oxyacetylene flame tests. The results demonstrated that, in comparison to uncoated ablators, the ALD-modified samples exhibited enhanced performance in terms of mass loss and surface recession: compared to uncoated ablators, the former was 14% lower and the latter was diminished by 50%. Moreover, the morphological characterization of the tested specimens revealed a significantly reduced degree of oxidation of the coated fibers which were directly exposed to the flame. [ABSTRACT FROM AUTHOR]

Copyright of China Synthetic Fiber Industry is the property of Sinopec Baling Petrochemical Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)