Search

Carbon‐based materials are widely deployed in carbon capture but are only limited to physisorption procedures. Further extending functionalized carbon materials to CO2 chemisorption under low CO2 concentration is highly desirable yet challenging. Herein, a carbon fiber composed of solely ultra‐micropores (∼0.45 nm) was deployed as the precursor to avoid the pore blocking effect, which was modified by superbase‐derived ionic liquids (ILs) containing strong interaction sites with CO2. By forming a thin coating layer on the surface, the as‐afforded surface‐functionalized fiber materials demonstrated enhanced CO2 uptake capacity and improved CO2 sorption kinetics, as evaluated by both the volumetric method and thermogravimetric analysis, as well as the calculated energy distribution curves. The achievements made in this work provide guidance on the functionalization of carbon‐based materials towards enhanced CO2 chemisorption by forming a thin layer of selected IL coating. [ABSTRACT FROM AUTHOR]

Functionalized silicon dioxide nanoparticles (nano-fSiO2) were uniformly deposited on the surface of carbon fibers (CFs) using a coating process which consisted of immersing the fibers directly in a suspension of nano-fSiO2 particles and epoxy monomers in 1-methyl-2-pyrrolidinone (NMP). The 0° flexural properties, 90° flexural properties, and Interlaminar shear strength (ILSS) mechanical properties of unidirectional epoxy composites made with nano-fSiO2+epoxy sized carbon fibers, with control fibers, and with epoxy-only sized fibers were measured and compared. An obvious increase of the fiber/matrix adherence strength was obtained with the nano-fSiO2+epoxy coating. The nano-fSiO2+epoxy sized CF/epoxy composites showed a relative increase of 15%, 50%, and 22% in comparison to control fibers, for the Interlaminar shear strength, the 90° flexural strength and the 90° flexural modulus, respectively, but little e difference was measured between the different systems for the 0° flexural properties. The observation of the fracture surfaces by scanning electron microscopy of composite fracture confirmed the improvement of the interfacially dependent mechanical properties. POLYM. COMPOS., 38:1474-1482, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this study, a novel method consisting of coating carbon fibers (CF) with graphite nanoplatelets (GnP) is investigated for its ability to modify the mechanical properties in the interphase region. Coating the CF was achieved by immersing CF in a solution of GnP dispersed in an epoxy-based solution for a few seconds. The influence of the processing conditions on the properties of the coating (thickness, homogeneity, quality of the GnP dispersion) is reported. Interfacial adhesion and the associated failure modes were evaluated by the single fiber fragmentation test. The maximum value of interfacial shear strength (IFSS) was achieved when a relative GnP concentration of 7.9 wt% on CFs, which led to 45 and 34% improvements in IFSS in comparison with the non-coated CF and epoxy coated CF, respectively. POLYM. COMPOS., 37:1549-1556, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A reactive sizingwas designed to achieve high levels of interfacialadhesion and improved mechanical properties with a carbon fiber–acrylatesystem cured by electron beam (EB). The sizing was made of a partiallycured epoxy sizing with a high density of pendant functional groups(acrylate functionality) to facilitate covalent bonding with the matrix.The interlaminar shear strength improved from 61 to 81 MPa (+33%)without postprocessing, reaching a shear strength similar to thatof the same system cured by a thermal treatment. Observation of thefracture profiles clearly highlighted a change in the fracture mechanismfrom a purely adhesive failure to a cohesive failure. To the bestof our knowledge, such improvements of the mechanical properties ofcarbon fiber composites cured by EB, without any postcure, have notbeen reported previously. This constitutes a breakthrough for theindustrial development of EB curing of composites. [ABSTRACT FROM AUTHOR]

The development of technologies to tune lignin properties for high-performance lignin-based materials is crucial for the utilization of lignin in various applications. Here, the effect of methanol (MeOH) fractionation on the molecular weight, molecular weight distribution, glass transition temperature ( Tg), thermal decomposition, and chemical structure of lignin were investigated. Repeated MeOH fractionation of softwood Kraft lignin successfully removed the low-molecular-weight fraction. The separated high-molecular-weight lignin showed a Tg of 211 °C and a char yield of 47 %, much higher than those of as-received lignin ( Tg 153 °C, char yield 41 %). The MeOH-soluble fraction of lignin showed an increased low-molecular-weight fraction and a lower Tg (117 °C) and char yield (32 %). The amount of low-molecular-weight fraction showed a quantitative correlation with both 1/ Tg and char yield in a linear regression. This study demonstrated the efficient purification or fractionation technology for lignin; it also established a theoretical and empirical correlation between the physical characteristics of fractionated lignins. [ABSTRACT FROM AUTHOR]

Recent advances in large‐scale additive manufacturing (AM) with polymer‐based composites have enabled efficient production of high‐performance materials. Cellulose nanomaterials (CNMs) have emerged as bio‐based feedstocks due to their exceptional strength and sustainability. However, challenges such as hornification and poor dispersion in polymer matrices still limit large‐scale CNM–polymer composite manufacturing, requiring novel strategies. This review outlines an approach starting with atomic‐level simulations to link molecular composition to key parameters like bulk density, viscosity, and modulus. These simulations provide data for finite element analysis (FEA), which informs large‐scale experiments and reduces the need for extensive trials. The strategy explores how atomic interactions impact the morphology, adhesion, and mechanical properties of CNM‐based composites in AM processes. The review also discusses current developments in AM, along with predictions of mechanical and thermal properties for structural applications, packaging, flexible electronics, and hydrogel scaffolds. By integrating experimental findings with molecular dynamics (MD) simulations and finite element modeling (FEM), valuable insights for material design, process optimization, and performance enhancement in CNM‐based AM are provided to address ongoing challenges. [ABSTRACT FROM AUTHOR]