Modification of Cellulose Nanocrystals With 2-Carboxyethyl Acrylate in the Presence of Epoxy Resin for Enhancing its Adhesive Properties (original) (raw)
Related papers
2021
We synthesized the cellulose nanocrystals (CNCs) by using cotton as a raw material, then it was modified with 2-carboxyethyl acrylate to improve its adhesion and thermal properties. CNCs was chosen as a modifier to improve the interfacial adhesion between the reinforced nanocrystals and E-51 epoxy resin system. This gives a better modulus of elasticity, a lower coefficient of energy, and thermal expansion. Significant improvements in modulus properties, strength, transparency and thermal stability were observed with modified cellulose nanocrystals (MCNCs) compared with the standard sample. SEM, and transmission electron microscope (TEM), powder diffraction (XRD), (TGA and DTG) and Fourier transform infrared spectroscopy (FTIR) were used for the isolation of synthetic (native and modified) cellulose nanocrystals. In addition, the MCNCs adhesion properties with E-51 (Bisphenol A diglycidyl ether) epoxy resins were also investigated using the Zwick/Roell Z020 model.
Cellulose, 2014
Development of high-performance bionanocomposite adhesives is of high interest due to their environmentally friendly nature and superior mechanical properties in outdoor environments. Nano-crystalline cellulose (NCC) and resilin are among the most promising bio-nanofillers, providing strength and elasticity, respectively. A novel bionanocomposite comprised of NCC and resilin fused to a cellulose binding domain (Res.-CBD) is presented. As a case study, commercial epoxy adhesive was chosen as a matrix for the bio-nanocomposite adhesive. Insertion of hydrophilic NCC into hydrophobic resins, such as epoxy, is typically performed using solvent exchange, chemical modification, emulsifier addition or mixing with water-borne resins, techniques which either limit the material's application range or which are considered environmentally unfriendly. The unique approach presented here employed Res.-CBD as a surfactant-like agent supportive of the direct insertion of water-suspended NCC into an epoxy resin. The presented approach involves binding of Res.-CBD to NCC through its CBD domain and a chemical reaction between the resin epoxide groups and Res.-CBD amine moieties. The resulting bio-nano material shows a 50 % increase in the Young's modulus and a 20 % decrease in the tan(d), compared to pristine epoxy. This novel epoxy adhesive can be advantageous in applications where higher elasticity and Young's modulus are required. Keywords Nano-crystalline cellulose (NCC) Á Resilin Á Epoxy Á Bio-nanocomposites R. Verker and A. Rivkin have contributed equally to this work.
Journal of Inorganic and Organometallic Polymers and Materials, 2021
Bio-based epoxy resins are being used due to their green chemistry. They have better properties than petroleum-based epoxy resins. Recently, environment friendly nanomaterials have been used for different industrial applications. Cellulose nanocrystals (CNCs) are among the best naturally occurring materials. Therefore, the surface of cellulose nanocrystals are modi ed by eugenol-based silane coupling agent (EBSCA). Chemical composition and surface morphologies of CNCs were analyzed and characterized by FTIR, AFM, SEM, TEM and 1 H-NMR. The SEM and AFM results con rmed eugenol-based silane coupling agent was successfully grafted on cellulose nanocrystals. Modi ed CNCs demonstrated an excellent tensile strength (2190 MPa) and modulus (16.00 MPa), as well as storage modulus (1622 MPa) exhibited by 1wt% modi ed cellulose nanocrystals composites. Additionally, modi ed CNCs displayed hydrophobic behavior (CA=102 ± 2°). The corresponding modi ed CNCs have signi cant applications in combination of high stiffness and strength to the epoxy resins. This study lays a foundation towards full bio-based, environment friendly polymers fabrication and consumptions most desirable in adhesive and mechanical industrial elds.
Cellulose, 2021
Nanocellulose is abundant, renewable, biocompatible, and a good candidate as reinforcement agent in nanocomposites; however, its hydrophilicity leads to poor dispersion in hydrophobic polymers. Recently, both in situ polymerization and cellulose surface modification have been used to improve dispersion, but emulsion polymerization is rarely adopted, and when it is, the reinforcement agent is usually cellulose nanocrystal (CNC), with gain in mechanical properties being the main focus of the research. Therefore, this work aims to explore the influence of adding either CNC or microfibrillated cellulose (MFC), both without surface modification, on the mechanical resistance, thermal degradation, and water vapor permeability of poly(vinyl acetate) composites obtained by either in situ emulsion polymerization or mixing. The results showed that despite having similar impacts on thermal and barrier properties, MFC and CNC affect the mechanical properties of their composites differently. Both cause decrease of the thermal degradation rate and do not have a significant impact on water vapor permeability. However, the addition of CNC during synthesis increased composite mechanical resistance significantly while the addition of MFC did not show improvement. Mechanical resistance is also strongly dependent on the procedure used to produce the composites.
Biomacromolecules, 2018
A critical aspect in materials design of polymer nanocomposites is the nature of the nanoparticle/polymer interface. The present study investigates the effect of manipulation of the interface between cellulose nanofibrils (CNF) and poly(methyl methacrylate) (PMMA) on the optical, thermal and mechanical properties of the corresponding nanocomposites. The CNF/PMMA interface is altered with a minimum of changes in material composition, so that interface effects can be analyzed. The hydroxyl-rich surface of CNF fibrils is exploited to modify the CNF surface, via an epoxide-hydroxyl reaction. CNF/PMMA nanocomposites are then prepared with high CNF content (~38 wt.%) using an approach where a porous CNF mat is impregnated with monomer or polymer. The nanocomposite interface is controlled by either providing PMMA-grafts from the modified CNF surface or by solvent-assisted diffusion of PMMA into a CNF network (native and modified). The high content of CNF fibrils of ~6 nm diameter leads to strong interface and polymer matrix distribution effects. Moisture uptake and mechanical properties are measured at different relative humidity conditions. The nanocomposites with PMMA molecules grafted to cellulose exhibited much higher optical transparency, thermal stability and hygro-mechanical properties than the control samples. The present modification and preparation strategies are versatile, and may be used for cellulose nanocomposites of other compositions, architectures, properties and functionalities.
Cellulose Nanocrystals-A material with Unique Properties and Many Potential Applications
2013
Introduction Cellulose nanocrystals (CNCs) are cellulose-based nanoparticles that can be extracted by acid hydrolysis from a wide variety of natural source materials (e.g., trees, annual plants, tunicates, algae, bacteria) [1-7]. These rod-like or whisker-shaped particles (Fig. 1, 3–20 nm wide, 50–2000 nm long) have a unique combination of characteristics: high axial stiffness (~150 GPa), high tensile strength (estimated at 7.5 GPa), low coefficient of thermal expansion (~1 ppm/K), thermal stability up to ~300°C, high aspect ratio (10–100), low density (~1.6 g/cm3), lyotropic liquid crystalline behavior, and shearthinning rheology in CNC suspensions. The exposed – OH groups on CNC surfaces can be readily modified to achieve different surface properties and have been used to adjust CNC self-assembly and dispersion for a wide range of suspensions and matrix polymers and to control interfacial properties in composites (e.g., CNC-CNC and CNC-matrix). This unique set of characteristics r...
Biomedical Journal of Scientific & Technical Research, 2021
Cellulose nanocrystals (CNCs) is one of the outstanding nanomaterial. So far, much researcher nowadays has been developed their properties. These properties make CNCs a promising resource to replace fossil resources for the production of industrial materials and chemicals. Here, we firstly modified cellulose nanocrystals with 3-Glycidoxypropyltrimethoxy (KH-560) silane coupling agent. Chemical composition and surface morphologies of cellulose nanocrystals were analyzed and characterized by FT-IR, and SEM. The result indicated that polar hydroxyl groups were successfully introduced on the cellulose nanocrystals surface. The SEM results confirmed silane coupling agent was successfully grafted on cellulose nanocrystals. Modified CNCs demonstrated an excellent tensile strength and modulus exhibited by 1wt% modified cellulose nanocrystals composites. This novel procedure improves the dispersion of cellulose nanocrystals by modification and at the same time enhance the interfacial adhesion. Result shows increases more over than the native cellulose nanocrystals by modifying CNCs with KH-560 coupling agent. This study lays a foundation towards full polymers fabrication and consumptions most desirable in adhesive and mechanical industrial fields.
Cellulose nanocrystal: A promising toughening agent for unsaturated polyester nanocomposite
Polymer, 2015
New nanocomposites of an unsaturated polyester resin (UPR) and cellulose nanocrystals (CNCs) were prepared. Effects of CNC silane surface treatment on the morphology, mechanical and thermal properties, viscoelastic behavior and water absorption of CNC reinforced UPR have been studied. The results showed that the crystallinity index of the CNCs reduced after the surface treatment. However, it did not impact the size and aspect ratio of the rod-like nanoparticles. Tensile tests showed that both the strength and stiffness of the UPR improved upon the incorporation of silane treated CNCs (STCNCs), whereas no significant changes were observed on the impact energy after the treatment. Interestingly, the impact energy increased significantly with the addition of untreated CNCs. The viscoelastic behavior and thermal degradation for both the CNC and STCNC-reinforced nanocomposites were improved. The waterabsorption behavior of the UPR was found to decrease upon incorporation of CNCs, and a further reduction was observed with STCNCs.
Cellulose nanomaterials as green nanoreinforcements for polymer nanocomposites
Philosophical transactions. Series A, Mathematical, physical, and engineering sciences, 2018
Unexpected and attractive properties can be observed when decreasing the size of a material down to the nanoscale. Cellulose is no exception to the rule. In addition, the highly reactive surface of cellulose resulting from the high density of hydroxyl groups is exacerbated at this scale. Different forms of cellulose nanomaterials, resulting from a top-down deconstruction strategy (cellulose nanocrystals, cellulose nanofibrils) or bottom-up strategy (bacterial cellulose), are potentially useful for a large number of industrial applications. These include the paper and cardboard industry, use as reinforcing filler in polymer nanocomposites, the basis for low-density foams, additives in adhesives and paints, as well as a wide variety of filtration, electronic, food, hygiene, cosmetic and medical products. This paper focuses on the use of cellulose nanomaterials as a filler for the preparation of polymer nanocomposites. Impressive mechanical properties can be obtained for these material...
CELLULOSIC NANOCOMPOSITES: A REVIEW
2000
Because of their wide abundance, their renewable and environmentally benign nature, and their outstanding mechanical properties, a great deal of attention has been paid recently to cellulosic nanofibrillar structures as components in nanocomposites. A first major challenge has been to find efficient ways to liberate cellulosic fibrils from different source materials, including wood, agricultural residues, or bacterial cellulose. A second major challenge has involved the lack of compatibility of cellulosic surfaces with a variety of plastic materials. The water-swellable nature of cellulose, especially in its non-crystalline regions, also can be a concern in various composite materials. This review of recent work shows that considerable progress has been achieved in addressing these issues and that there is potential to use cellulosic nano-components in a wide range of high-tech applications.