Table 2 - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
The T g for polystyrene matrices and SiO 2 -PS com- posites. The composites are labeled with vol.% of SiO 2 only.
Source publication
Polymer nanocomposites have improved mechanical, optical and thermal properties compared to traditional thermoplastics. To study the impact of grafted brush–matrix interactions on the mechanical properties of nanoparticle filled polymers, uniaxial tensile testing with digital image correlation (DIC) was done on polystyrene (PS) grafted SiO2 in low...
Contexts in source publication
Context 1
... for amorphous polymers the T g is very important. The T g values are shown in Table 2 below. The 100k PS composites and matrix T g values are within error of each other. ...
Similar publications
Surface functionalization of silica nanoparticles (SiNP) has gained attention as an efficient methodology in improving the properties of the proton exchange membrane (PEM). Here, we report the development of block copolymer grafted SiNP (BC-g-SiNP) as functional nanofiller which was further blended with oxypolybenzimidazole (OPBI) to prepare nanoco...
Citations
... As a result, the gluecoated scanning probe provides better compliance at the contact when it is pushed against the sandpaper under a normal load. Meanwhile, mixing the nanoparticles into the glue reduces the adhesion of the probe to the sandpaper and strengthens the mechanical properties of the glue 43 . ...
Friction between two rough solid surfaces often involves local stick-slip events occurring at different locations of the contact interface. If the apparent contact area is large, multiple local slips may take place simultaneously and the total frictional force is a sum of the pinning forces imposed by many asperities on the interface. Here, we report a systematic study of stick-slip friction over a mesoscale contact area using a hanging-beam lateral atomic-force-microscope, which is capable of resolving frictional force fluctuations generated by individual slip events and measuring their statistical properties at the single-slip resolution. The measured probability density functions (PDFs) of the slip length δxs, the maximal force Fc needed to trigger the local slips, and the local force gradient k′\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${k}^{{\prime} }$$\end{document} of the asperity-induced pinning force field provide a comprehensive statistical description of stick-slip friction that is often associated with the avalanche dynamics at a critical state. In particular, the measured PDF of δxs obeys a power law distribution and the power-law exponent is explained by a new theoretical model for the under-damped spring-block motion under a Brownian-correlated pinning force field. This model provides a long-sought physical mechanism for the avalanche dynamics in stick-slip friction at mesoscale.
... Chemical interactions with PS are facilitated by incorporating appropriately functionalized POSS, as in the case of POSS cages with vinyl or vinylidene moieties. The mechanical properties of SiO 2 -PS composites with grafted chain conformation were dependent on the P/N ratio [118], where P is the degree of polymerization of the matrix and N is the degree of polymerization of the grafted brush. High composite strength is expected at N~P, with swollen grafted chains. ...
... Chemical interactions with PS are facilitated by incorporating appropriately functionalized POSS, as in the case of POSS cages with vinyl or vinylidene moieties. The mechanical properties of SiO2-PS composites with grafted chain conformation were dependent on the P/N ratio [118], where P is the degree of polymerization of the matrix and N is the degree of polymerization of the grafted brush. High composite strength is expected at N ~ P, with swollen grafted chains. ...
Several environmental and techno-economic assessments highlighted the advantage of placing polystyrene-based materials in a circular loop, from production to waste generation to product refabrication, either following the mechanical or thermochemical routes. This review provides an assortment of promising approaches to solving the dilemma of polystyrene waste. With a focus on upcycling technologies available in the last five years, the review first gives an overview of polystyrene, its chemistry, types, forms, and varied applications. This work presents all the stages that involve polystyrene’s cycle of life and the properties that make this product, in mixtures with other polymers, command a demand on the market. The features and mechanical performance of the studied materials with their associated images give an idea of the influence of recycling on the structure. Notably, technological assessments of elucidated approaches are also provided. No single approach can be mentioned as effective per se; hybrid technologies appear to possess the highest potential. Finally, this review correlates the amenability of these polystyrene upcycling methodologies to frontier technologies relating to 3D printing, human space habitation, flow chemistry, vertical farming, and green hydrogen, which may be less intuitive to many.
... For comparison, the water absorption of epoxy resin-based biocomposites with expanded graphite was decreased with an increased amount of the hydrophobic filler [23]. In order to thoroughly investigate the relationship between internal structure of composites and their macroscopic properties, the scanning electron microscopy images of their cross-sections should be taken [29]. This could provide an insight into a such bulk phenomena as aggregation, dispersion, and orientation of microparticles which would allow researchers to estimate interactions at the microparticle/epoxy resin matrix interface. ...
The aim of the research presented in the paper was to obtain new polymer composites with strong functional properties on the Epidian 5 epoxy resin matrix. The polymer composites contained admixtures of expanded graphite, powder graphite, birch bark containing botulin, and yellow dextrin in set amounts of 20% by weight. Their various mechanical parameters and physicochemical properties were investigated. The research involved determining the effect of a constant magnetic field with magnetic induction B, under the influence of which the parameters and properties of polymer composites have been changed. For example, in a constant magnetic field with an induction of B = 0.5 T there was an increase in the hardness of the composite with an admixture of birch bark from 24.01 to 26.96 N/mm2 (12.3%), or in the composite with the addition of yellow dextrin from 26.12 to 29.93 N/mm2 (14.6%). It was also found, for example, that the water absorption of the resin itself decreased from 0.18% to 0.13%, and the composite with graphite powder from 0.48% to 0.46%. Changes in these parameters, often beneficial, may be important in terms of potential application of those new materials in industry as alternatives.
... The shape, properties, and extent of the constituent, as well as the interfacial interactions of the matrix and the dispersed phase, all influence the properties of composites. Nanoparticles, [5] nanofibers, [6] and nanoclays [7] are types of nanomaterials used in fabrication composites. When the size of one of the constituents of the composite is on a nanometric scale, the word nanocomposites (NCs) suits more. ...
Polymer nanocomposites are materials that are prepared by incorporating nanoparticles into polymer matrices. In the last few decades, polymer nanocomposites have been investigated extensively and had undergone tremendous advancements. Transparent nanocomposites are of particular interest among several polymer nanocomposites due to the wide variety of applications. Therefore, this article aims to provide consolidated and in-depth knowledge about the capabilities of transparent polymers when combined with various nanoparticles like metal oxide, metal, semiconductor, carbon-based nanocomposites, etc. Challenges and future scope are also covered along with the synthesis, characterization and applications.
... The fracture surface of the composites exhibited short and disorderly cracks when the content of KH550-AlOOH was 0.6 wt%, as shown in Fig. 10d, and KH550-AlOOH evenly dispersed in the matrix and the strong interaction made the crack directions of the composite change and present arborization when the composite was subjected to external forces. The reasons were possible, first of all, nanoparticles as the stress concentration point, it pinned craze and kept it from developing cracks [36,37], and at the same time, a large number of craze and shear zones were formed which expended a lot of fracture energy, and the toughness of the material had been observably improved [38]. Secondly, KH550-AlOOH@GO existed in the matrix with a special lamellar structure, and when composite was subjected to the external force, the stress was absorbed by the lamella through the interface between composite and particles, and the residual stress fractured at the sharp corners of the lamella to produce holes and a large number of micro-cracks, and the stress field interacted strongly around the nanoparticles. ...
Graphene oxide (GO) was obtained by improved Hummers method; the pseudoboehmite (AlOOH) nanoparticles were prepared with aluminum isopropoxide by Sol–Gel method and modified by the silane coupling agent (KH-550) to get KH550-AlOOH. GO was coated by KH550-AlOOH to gain KH550-AlOOH@GO component. In the meantime, the matrix (E51-BCE) was synthesized from epoxy resin (E51) and bisphenol A cyanate (BCE). KH550-AlOOH@GO/E51-BCE composites were prepared via in situ polymerization, E51-BCE as the matrix and KH550-AlOOH@GO as the reinforcement. The micro-morphology of KH550-AlOOH@GO was investigated by Fourier transform infrared spectrometer (FT-IR) and transmission electron microscope (TEM), and the results showed that KH550-AlOOH was well distributed on the GO sheet and with abundant hydroxyl groups on its surface. The X-ray diffraction (XRD) and scanning electron microscope (SEM) of KH550-AlOOH@GO/E51-BCE composites indicated that KH550-AlOOH@GO was uniformly dispersed in E51-BCE matrix and there was a good interaction between them, which was conducive to the performances of the composite material. Mechanical and dielectric properties of composite also were tested and analyzed. The highest bending strength, bending modulus, and impact strength of KH550-AlOOH@GO/E51-BCE composites were 158.23 MPa, 2.37 GPa, and 46.96 kJ/m², respectively, when the content of KH550-AlOOH@GO was 0.6 wt%, which were 15.72%, 22.42%, and 198.22% higher than those of the matrix resin, respectively. The dielectric constant and dielectric loss of the composite were 3.12 and 0.0027 at 100 Hz.
... The data on filler particle sizes are summarized in Table 2. Mechanical properties of polymer composites were shown to be noticeably improved with an increase in the axial ratio of nanoparticles [28,29], but this holds true at low filler concentrations. For spherical dispersed particles an increase in strength or elastic modulus of polymer composites was observed at filler concentrations even over 20% [30]. An introduction of carbon nanotubes provided the increase of strength and stiffness of composites at a few percent or even tenths of a percent [31,32]. ...
The paper presents a comprehensive analysis of the elastic properties of polystyrene-based nanocomposites filled with different types of inclusions: small spherical particles (SiO2 and Al2O3), alumosilicates (montmorillonite, halloysite natural tubules and mica), and carbon nanofillers (carbon black and multi-walled carbon nanotubes). Block samples of composites with different filler concentrations were fabricated by melt technology, and their linear and non-linear elastic properties were studied. The introduction of more rigid particles led to a more profound increase in the elastic modulus of a composite, with the highest rise of about 80% obtained with carbon fillers. Non-linear elastic moduli of composites were shown to be more sensitive to addition of filler particles to the polymer matrix than linear ones. A non-linearity modulus βs comprising the combination of linear and non-linear elastic moduli of a material demonstrated considerable changes correlating with those of the Young’s modulus. The changes in non-linear elasticity of fabricated composites were compared with parameters of bulk non-linear strain waves propagating in them. Variations of wave velocity and decay decrement correlated with the observed enhancement of materials’ non-linearity.
... It is also identified that, the grafting ratio has a direct impact on the characters such as Youngs modulus, shear modulus and poisson's ratio [45,46]. The ratio between degree of polymerization (P) and the degree of polymerization of the grafted bush (N), P/N ratio has also had a predominant influence on the mechanical characters of the composite and this has been identified in a research on nanosilica reinforced on to the polystyrene matrix [47,48]. Several studies have been to assess the influence of ceramic nanomaterials. ...
The need of structural materials is inevitable for machineries, equipment's and tools. These materials are mostly made up of metals and polymeric composites and with other materials in rare cases. Polymeric composites nowadays replace almost all materials due to its improved characters and reduced manufacturing costs. The characters of these polymeric composites are improved by reinforcing multiple fibers in it and thus enhances its suitability for different applications. Among the characters of a composites, weight reduction is a vital property that decides the usability of the material in high end applications like aircraft, robots etc. Weight of composites could be enhanced without losing its characters by reinforcing nanoparticles in different forms. Several nanomaterials have been utilized by researchers in various forms and they are proven to be the best in enhancing the characters of the composites. The present research gives a clear picture on the different challenges during the synthesis, fabrication and characterization of nanoparticles reinforced plastic composites.
... The instrumentation of mechanical test setups with physical sensors for characterization of deformation and damage initiation and evolution during a mechanical loading is the state of the art for various materials [11][12][13]. Monitoring of material reactions, like deformation [14], change in temperature [15] or electrical resistance [16], and acoustic emissions [17,18], allows an assessment of the structural integrity and identification of occurring damage mechanisms of the tested specimen before final failure [19]. By combining mechanical testing with analytical techniques, like scanning electron microscopy (SEM) or microfocus computer tomography (µCT), an optical characterization of microstructural changes during loading can be realized and correlated with the macroscopic deformation behavior [20]. ...
Cottonid is a layered material based 100% on cellulose that holds excellent material properties by being completely sustainable. The finite nature of petroleum-based resources nowadays makes these properties significant for technical applications again. To understand how Cottonid reacts to application-oriented mechanical loads and how it fails, development of microstructural damage on the surface and in the volume of Cottonid was studied using innovative in situ testing techniques for the first time. Quasi-static tensile tests were comparatively performed in a scanning electron microscope as well as a microfocus computer tomograph, and the development of defects present in the initial condition of the material was investigated. In the elastic region, no visible damage initiation on the surface and a decrease of overall void volume within the gauge length could be detected. When reaching the yield strength, crack initiation on the surface starts at critical areas, like pores and microcracks, which propagation and assembly could be visualized via scanning electron micrographs. In the plastic region, an increase in void volume could be shown in the gauge length until final failure of the specimen. Innovative material testing techniques presented in this study support lifetime estimation in technical applications and understanding of process-structure-property relations. Particularly, characterization of microstructural damage development due to a mechanical load, which leads to final failure of the specimen, is essential to be able to create material models for lifetime prediction in respect to variable manufacturing or application parameters.
... As known [25,26] with an increase in the axial ratio of nanoparticles, an increase in the mechanical properties of polymer composites is observed at lower concentrations. So with the introduction of spherical dispersed particles, an increase in strength or elastic modulus of polymer composites is observed at filler concentrations more than tens of percent [27], but, for example, with the introduction of carbon nanotubes, the increase of strength and stiffness of composites is already observed with the introduction a few percent or tenths of a percent [28,29]. It was shown in the works that in cases of intercalation of macromolecules and dispersion to individual nanolayers with a thickness of about 1 nm, the properties of polymer composites significantly improve already at low degrees of their filling with layered silicates [30,31,32]. ...
The paper presents a comprehensive analysis of elastic properties of polystyrene-based nanocomposites filled with different types of inclusions: small spherical particles (SiO2 and Al2O3), alumosilicates (montmorillonite, halloysite natural tubules and Mica) and carbon nanofillers (carbon black and multi-walled carbon nanotubes). Composites were fabricated by melt technology. The analysis of composite melts showed that the introduction of Montmorillonite, Multi-walled carbon nanotubes, and Al2O3 particles provided an increase in melt viscosity by an average of 2 to 5 orders of magnitude over the pure polystyrene. Block samples of composites with different filler concentrations were prepared, and their linear and nonlinear elastic properties were studied. The introduction of more rigid particles led to a more profound increase in the elastic modulus of the composite, with the highest rise of about 80% obtained with carbon fillers. Carbon black particles provided also an enhanced strength at break of about 20% higher than that of pure polystyrene. The nonlinear elastic moduli of composites were shown to be more sensitive to addition of filler particles to the polymer matrix than the linear ones. The nonlinearity coefficient $\beta$ comprising the combination of linear and nonlinear elastic moduli of a material demonstrated considerable changes correlating with changes of the Young's modulus. The absolute value of $\beta$ showed rise in 1.5-1.6 times in the CB- and HNT-containing composites as compared to that of pure PS. The changes in nonlinear elasticity of fabricated composites were compared with measurements of the parameters of bulk nonlinear strain waves in them. Variations of wave velocity and decay decrement correlated with observed enhancement of materials nonlinearity.
... The enhancement of mechanical properties in non-grafted nanocomposite blends has been successfully estimated using the Guth equation 124 based on hydrodynamic interactions between the nanoparticle and polymer matrix in which the rubbery modulus increases over the neat value by the factor 1 + 0.67φ + 1.62φ 2 where φ is the volume fraction of reinforcement. 89,125,126 In polymer-grafted nanocomposite systems, on the other hand, researchers have shown that mechanical reinforcement takes place by the percolation of nanoparticles that act as network junctions with the grafted polymer chains serving as the bridges between adjacent junctions. 54,57,127,128 As the matrix-free grafted nanocomposite systems contain only the polymer-grafted nanoparticles, the nanoparticle contribution to mechanical reinforcement will be effective only if the grafted chains on neighboring particles entangle among themselves. ...
