Characterization of optical,thermal and electrical properties of SWCNTs/PMMA nanocomposite films

The optical, thermal and electrical behavior of single-wall carbon nanotubes (SWCNTs)/poly(methyl methacrylate) (PMMA) composite are studied as a function of SWCNTs concentration. The nanocomposites were prepared in the form of films by solution casting technique. The concentrations of SWCNTs in SWCNTs/PMMA films were 0, 0.5, 1, 1.5, 2, 3.5, 5, 7.5, and 10 wt%. High-resolution transmission electron microscopy showed that SWCNTs doped in PMMA is less fragmented as compared to the powder SWCNTs. This is due to the interactions with polymers as well as the fabrication method. X-ray diffraction patterns of SWCNTs/PMMA composite films indicated that there is no covalent interaction between SWCNTs and PMMA. In addition, it demonstrates a homogeneous dispersion of SWCNTs in PMMA matrix. The optical properties of SWCNTs/PMMA films of SWCNTs concentration from 0 to 2.0 wt% have shown that the absorption intensity of the composite was enhanced ≈8.5 times as compared to the plain PMMA. Photoacoustic spectroscopy technique was used as a powerful and non-destructive tool to determine the thermal diffusivity (α), thermal effusivity (e) and thermal conductivity (k). The composites exhibited ≈160 % improvement in k at 2.0 wt%. Furthermore, the DC electrical conductivity measurements of SWCNTs/PMMA showed that the percolation threshold value was about 2.0 wt% of SWCNTs loading.     

Effect of SWCNT dispersion on epoxy nanocomposite properties

In nanocomposites containing single wall carbon nanotubes (SWCNTs), the final properties strongly depend on the dispersion quality of these fillers. Various methods have been used to improve the dispersion of nanofillers; however, one of the most effective ways is to functionalize carbon nanotubes (CNTs) with covalent and noncovalent functional groups. In this work, the dispersion of SWCNTs in an epoxy system was studied by using surfactants, acid (COOH), and ester groups (PGE)‐modified CNTs. Rheological and scanning electron microscopy analysis showed that functionalization of CNTs helped in improving the dispersion of fillers in the epoxy matrix. Systems with surfactant modified SWCNTs (1 wt%) exhibited the highest storage modulus at low frequencies after 5‐min sonication. This behavior is associated to a stronger network of fillers as a result of a good dispersion. However, longer sonication times lowered the storage modulus, corresponding to a degradation of the tubes. The effect of the dispersion quality on mechanical properties was also studied using a three‐point bending set‐up. POLYM. COMPOS.,, 2012. © 2012 Society of Plastics Engineers     

Morphology evolution induced by carbon nanotubes on thermal and mechanical characters of semi-crystalline aromatic polyimide

A series of nanocomposites based on a new semi-crystalline polyimide (PI) and multi-walled carbon nanotubes (MWCNTs) were prepared by in situ polymerization. The TEM measurement reveals the improved dispersion of carboxylic acid-functionalized MWCNTs (COOH-MWCNTs) in semi-crystalline PI compared with pristine MWCNTs. The TGA analysis show that the concentration of carboxylic acid groups on the surface of nanotubes is about 4.34 wt%. The FT-IR spectroscopy analysis indicate that the imide rings of the PI interact non-covalently with nanotubes. The Polarized optical microscopy observation reveals significant morphology evolution in semi-crystalline PI induced by MWCNTs. The SEM micrographs suggest the strong interfacial interaction between COOH-MWCNTs and PI main chains, and significant changes in the fracture surfaces morphology. The WAXRD measurements reveal that COOH-MWCNTs promote the semi-crystalline PI crystallinity and structure change. COOH-MWCNTs can more efficiently improve the mechanical and thermal properties of resulting nanocomposites than pristine MWCNTs. COOH-MWCNT/PI nanocomposites show increases of Young’s modulus and yield strength, as high as 20–30 %, without sacrificing the elongation at break at loadings of 0.5 wt% nanotubes. Furthermore, with increasing the loadings of COOH-MWCNTs to 1.0 wt%, Young’s modulus and yield strength decrease due to nanotube aggregation, but elongation at break increase about 46 %. An abrupt increase of elongation at break in pristine MWCNT/PI nanocomposites was also registered at nanotubes loadings increasing from 0.5 to 1 wt%. These results indicate that the properties of semi-crystalline PI nanocomposites reinforced with carbon nanotubes are not only determined by the dispersion of nanotubes in the PI matrix and their interfacial interactions, but also by the crystalline phase morphology evolution in the PI matrix.     

Study on the properties of multi-walled carbon nanotubes reinforced poly (vinyl alcohol) composites

Nanocomposite films based on polyvinyl alcohol(PVA) and multi-walled carbon nanotubes (MWCNTs) at different weight ratios (i.e.0.0,0.5, 1.0,1.5, 2.0 wt%), were prepared by dispersion techniques. Cationic geminisurfactant and its monomeric form (0.01 wt%) were used as dispersants to achieve homogeneous and stable dispersionof CNTs in water and subsequent PVA/CNTs nanocomposites. Surface charge of CNTs in aqueous suspension with addition of the used dispersants were investigated by measuring its zeta potential. The structural and interaction studies have been analyzed from X-ray diffraction (XRD) and Raman spectroscopy. The effect of the used surfactantson the separation and distribution of CNTs in PVA matrix was studied by visual characterization based on scanning electron microscopy (SEM). Thermal, mechanical and electrical properties of the prepared nanocomposites were evaluated and the results were discussed in relation with the CNTs content and surfactant type as dispersant. Surfactant effect improved the dispersion homogeneity of CNTs (at 1.0 wt%) within the polymer matrix. The physical interaction between. CNTs and PVA macromolecular chains resulting in nanocomposites with largely enhanced properties compared to those prepared with higher filler loading by avoiding the agglomeration phenomenon of nanotubes. On the other hand, the addition of CNTs by content up to 2 wt%, increases the electrical conductivity to be 10^?6 Scm^?1 at room temperature which highly recommends such composites to be used in electrostatic dissipation applications upon using gemini surfactant. Furthermore, useful nanosized capacitor structure based onnanocomposites containing its monomeric form, characterized by high permittivity and low dielectric loss, can be formed.     

Facile way to disperse single‐walled carbon nanotubes using a noncovalent method and their reinforcing effect in poly(methyl methacrylate) composites

In this work, a noncovalent method was used to functionalize and thereby disperse single‐walled carbon nanotubes (SWCNTs) in dimethylformamide with poly[methyl methacrylate‐co‐(fluorescein O‐acrylate)] as a surfactant, and then the resultant poly(methyl methacrylate) (PMMA)‐based nanocomposites were fabricated via solution casting. The dispersion level of carbon nanotubes in the solvent was investigated by means of scanning electron microscopy and atomic force microscopy. The results showed that carbon nanotubes were well wrapped by the surfactant, and small carbon nanotube bundles several nanometers or less in diameter and several micrometers in length were obtained. Both scanning electron microscopy and transmission electron microscopy confirmed the uniform dispersion of SWCNTs in the PMMA matrix. The mechanical properties of the composites were determined with a universal tension tester. The PMMA composite containing 2 wt % SWCNTs showed improved tensile properties versus neat PMMA, showing 56 and 30% enhancements of the tensile modulus and tensile stress, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Investigation of the rheological,dynamic mechanical,and tensile properties of single‐walled carbon nanotubes reinforced poly(vinyl chloride)

Polymer nanocomposites consisting of single‐walled carbon nanotubes (SWCNTs) and poly(vinyl chloride) were prepared by casting technique. The complex viscosity increased with increasing SWCNTs content, and it had a percolation concentration threshold equal to 0.45 wt % of SWCNTs. The storage modulus, G′, increased with increasing either SWCNTs content or frequency. A gradual decrease in the terminal zone slope of G′ for the nanocomposites with increasing SWCNTs content may be explained by the fact that the nanotube–nanotube interactions will be dominant at higher CNTs content, and lead to the formation of the interconnected or network‐like structures of SWCNTs in the polymer nanocomposites. The rheological loss factor indicates two relaxation peaks at frequencies of 0.11 and 12.8 Hz due to the interaction between SWCNTs and polymer chains and glass transition, respectively. Dynamic mechanical properties were measured for the prepared composites. The results indicate that the storage modulus changes steadily, and the tanδ peaks are less intense for high SWCNTs content. Tensile tests were measured and depicted by an increase in the elastic modulus with increasing SWCNTs content, but it decreases for all composites as the testing temperature increased. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Effect of functionalized SWCNTs on microstructure of PP‐g‐MA/OMMT/f‐SWCNTs nanocomposite

The aim of this work was to study the effect of functionalized single‐walled carbon nanotubes (f‐SWCNTs) on the microstructure of PP‐g‐MA/organic modified montmorillonite (OMMT)/f‐SWCNTs ternary nanocomposite. Pristine SWCNTs were chemically modified by maleic anhydride to improve the interaction between PP‐g‐MA and nanotubes. The dispersion states of OMMT in the different nanocomposites were investigated by wide angle X‐ray diffraction. The morphologies of the nanocomposites were characterized by scanning electron microscopy. Crystallization behaviors of nanocomposites were studied through differential scanning calorimetry and polarizing optical microscopy. Different than the PP‐g‐MA/OMMT binary nanocomposite, in which the OMMT is mainly in an exfoliated state, the ternary PP‐g‐MA/OMMT/f‐SWCNTs nanocomposite exhibits mostly intercalated OMMT. Furthermore, in the ternary nanocomposite, the crystallization of polymer is mainly induced by f‐SWCNTs rather than by OMMT. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Influence of the Processing Route on the Carbon Nanotubes Dispersion and Creep Resistance of 3YTZP/SWCNTs Nanocomposites

3YTZP matrix composites containing 2.5 vol% of single‐walled carbon nanotubes (SWCNT) were fabricated by Spark Plasma Sintering (SPS) at 1250°C, following different processing routines with the aim of optimizing the SWCNTs dispersion throughout the ceramic matrix. Microstructural characterization of the as‐fabricated samples has been performed by means of scanning electron microscopy (SEM). The specimens have been crept at 1200°C to correlate creep resistance and SWCNTs distribution. There are no creep experimental results on these nanocomposites reported in literature. Mechanical results show that the incorporation of SWCNTs into a 3YTZP matrix produces an increase in the strain rate at high temperature with respect to monolithic zirconia. The creep resistance of these nanocomposites decreases with the improvement of the SWCNTs dispersion, where a smaller SWCNTs agglomerate size and consequently a higher concentration of carbon nanotubes surrounding the 3YTZP grain boundaries is found. This fact indicates that SWCNTs act as a lubricant making grain‐boundary sliding easier during deformation of these composites.     

Poly(vinyl chloride)/single wall carbon nanotubes composites: Investigation of mechanical and thermal characteristics

Composites of polyvinylchloride (PVC) with single wall carbon nanotubes (SWCNTs) were prepared by plastisol curing. Scanning electron microscopy (SEM) observations revealed that appropriate dispersion of the nanotubes was achieved. The mechanical properties showed that SWCNT improved the Young's modulus and tensile strength of the PVC. The composites have higher elongation at break and toughness as well. By comparing the mechanical properties of the composites, it is found that there is a critical SWCNT loading (about 1 wt%) below which the tensile properties increase with increasing nanofiller concentration. For the composites containing 0.25–0.75 wt% of SWCNT, this situation was observed, whereas for a sample with 1 wt% SWCNT, the mechanical properties decreased due to the agglomeration of the nanotubes. Thermogravimetric analysis indicated that the SWCNT increased T_5%, T_10%, T_50%, T_onset, and T_max and decreased weight loss in the degradation process of the PVC. In addition, by adding SWCNT to the polymer, residual mass at 600°C increased significantly. These results are advantages for the applications of the polymer in which high mechanical properties, including high tensile modulus and toughness, and good thermal properties are needed. J. VINYL ADDIT. TECHNOL., 22:128–133, 2016. © 2014 Society of Plastics Engineers     

Effect of Organomodified Ni-Al Layered Double Hydroxide (OLDH) on the Properties of Polypropylene (PP)/LDH Nanocomposites

This work addresses the effect of organomodified layer double hydroxide (OLDH) on the properties of PP/LDH nanocomposites prepared by melt intercalation method using a single screw extruder with maleic anhydride grafted polypropylene (PP-g-MA) as a compatibilizer. For this, Ni-Al LDH was first prepared by the co-precipitation method at constant pH using their nitrate salts. The above synthesized pristine LDH was organically modified using sodium dodecyl sulphate (SDS) by the regeneration method. The structural and thermal properties of LDH and PP nanocomposites were performed by X-ray diffraction (XRD), FTIR spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The influence of LDH loading on the mechanical and thermal properties of the nanocomposite was also investigated. The XRD results confirmed the formation of exfoliated PP/LDH nanocomposites. PP/LDH nanocomposites exhibited enhanced thermal stability relative to the pure PP. When 10% weight loss was selected as a point of comparison, the decomposition temperature of PP/LDH (5 wt%) nanocomposite was 15.3°C higher than that of pure PP. The DSC result indicated an increase in crystallization and melting temperature of the PP/LDH nanocomposites compared to pure PP. Overall, the mechanical properties of the PP/LDH nanocomposites increased with an increase in the LDH content. The maximum improvement of tensile strength, Young's modulus, flexural strength, and flexural modulus for the PP/LDH nanocomposite was found to be 11, 22.5, 28, and 22%, respectively, over neat PP. For comparison purposes, a nanocomposite with 5 wt% modified bentonite (PP/B5) was also prepared under the same operating condition and there was no significant improvement in mechanical properties (tensile strength and modulus).     

Carbon nanotube/polymer nanocomposites: A study on mechanical integrity through nanoindentation

Carbon nanotubes (CNTs) are under intense investigation in materials science owing to their potential for modifying the mechanical proprieties of their composites. In this work, nanomechanical and nanotribological properties of polymer composites, reinforced with multiwall carbon nanotubes (MWCNTs) and single wall carbon nanotubes (SWCNTs), have been studied using the nanoindentation and nanoscratch technique. In particular, three different epoxy resins reinforced using several percentage of two different types of MWCNTs have been studied (range 0–7 wt%). Another resin was reinforced using MWCNTs (range 0–2.5 wt%) and SWCNTs (range 0–5 wt%) as fillers. Hardness and elastic modulus using nanoindenter instrument have been evaluated, while the coefficient of friction of the nanocomposites is obtained using nanoscratch. The results show an evident dependence with the percentage of CNTs. For all types of resins, an optimum in nanomechanical properties is found at intermediate levels of CNTs filling. POLYM. COMPOS., 36:1432–1446, 2015. © 2014 Society of Plastics Engineers     

Mechanical Properties of Biodegradable Polyhydroxyalkanoates/Single Wall Carbon Nanotube Nanocomposite Films

The nanocomposite films of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxyoctanoate) (PHO) with single wall carbon nanotubes (SWCNTs), were prepared. The Optical microscopy showed that the crystalline size substantially decreased for PHB/SWCNTs nanocomposites with a 1 % weight fraction of SWCNTs relative to PHB (PHB/(1%)SWCNTs), indicating the effective nucleation of PHB crystallization by SWCNTs. Mechanical properties of the nanocomposite films were measured by nanoindentation. Both polymer nanocomposite films showed an increase in hardness (H) and Young’s modulus (E), with SWCNTs concentration. The PHB/SWCNTs nanocomposite films are found to be more brittle than neat PHB films.     

Properties of PMMA/Carbon nanotubes nanocomposites prepared by “grafting through” method

A number of batch polymerizations were performed to study the effect of multi‐walled carbon nanotubes (MWCNTs) on the properties of PMMA/MWCNTs nanocomposites. To improve the dispersion of nanotubes in PMMA matrix, MWCNTs were functionalized with methacrylate groups via a four‐step modification process and the modified nanoparticles were used to synthesize the nanocomposites. The prepared samples were characterized by Raman spectroscopy, thermogravimetric analysis, dynamic mechanical thermal analysis, differential scanning calorimetry, gel permeation chromatography, UV–visible, and TEM techniques. According to the results, modified nanotubes improved thermal and mechanical properties better than the pristine MWCNTs. The main improvement in the mechanical and thermophysical properties was achieved for the nanocomposite containing 0.5 wt% of MWCNTs. POLYM. COMPOS., 2012. © 2011 Society of Plastics Engineers     

Synergetic association of grafted PLA and functionalized graphene on the properties of the designed nanocomposites

The synergetic association of poly(lactic acid) grafted with maleic anhydride (MA-g-PLA) containing 0.44 wt% of maleic anhydride and epoxy-functionalized graphene (GFe) on the properties of the designed nanocomposites was studied. Rheological, mechanical and barrier properties of PLA nanocomposites were studied using different content of epoxy-functionalized graphene and MA-g-PLA compatibilizer. The PLA/MA-g-PLA/GFe nanocomposites prepared by melt blending, containing 5 wt% of MA-g-PLA, yield a maximum in storage modulus G′ and a rheological plateau at low frequencies, with a content of epoxy-functionalized graphene comprised between 4 and 7 wt%. This phenomenon was ascribed to a pseudo-solid behavior resulting from the high degree of epoxy-functionalized graphene exfoliation due to strong interfacial interactions with PLA and epoxy-functionalized graphene. The better mechanical and barrier performances were obtained with PLA/GFe containing 10 wt% of epoxy-functionalized graphene and 5 wt% of MA-g-PLA compatibilizer. The variation of the percentage of compatibilizer showed that 5 wt% of maleated PLA was sufficient to improve the thermal, rheological, mechanical and barrier properties of the PLA nanocomposite containing 7 wt% of epoxy-functionalized graphene.     

Carbon nanotube reinforced poly(trimethylene terephthalate) nanocomposites: Viscoelastic properties and chain confinement

Through a very facile route, a new class of nanocomposites involving poly(trimethylene terephthalate; PTT) and multiwalled carbon nanotubes (MWCNTs) was developed which was found to be high performance engineering material showing high modulus. Morphological, mechanical, viscoelastic, and thermal properties of the PTT nanocomposites with varying compositions of MWCNT were systematically studied and the results were analyzed. The dynamic mechanical and tensile properties of all the nanocomposites were seen to be enhanced with the addition of MWCNT and the sample containing 2 wt% MWCNT showing a storage modulus as much as 9.4 × 10⁸ GPa. The results were correlated with the morphological features obtained from scanning electron microscopy and transmission electron microscopy. Coefficient of effectiveness, degree of entanglement density, and reinforcement efficiency factor were estimated from the storage modulus values and, in addition, the degree of chain confinement also could be quantified. Furthermore, theoretical modelling was also done on the elastic properties of the composites. The crystallization temperature, glass transition temperature, and percentage crystallinity were estimated for all the nanocomposites and it was found that the sample with 3 wt% MWCNT content exhibited the highest glass transition temperature of 68.2°C. POLYM. ENG. SCI., 59:E435–E445, 2019. © 2018 Society of Plastics Engineers     

Effect of carbon nanotubes on the curing and thermomechanical behavior of epoxy/carbon nanotubes composites

The processing of carbon nanotube based nanocomposites is one of the fastest growing areas in materials research due to the potential of significantly changing material properties even at low carbon nanotube concentrations. The aim of our work is to study the curing and thermomechanical behavior of carbon nanotube/epoxy nanocomposites that are critical from an application standpoint. Multiwall carbon nanotubes–epoxy composites are prepared by solvent evaporation based on a commercially available epoxy system and functionalized multiwalled carbon nanotubes. Three weight ratio configurations are considered (0.1, 0.5, and 1.0 wt%) and compared to both the neat epoxy to investigate the nano‐enrichment effect. We focus here on the modification of the curing behavior of the epoxy polymer in the presence of carbon nanotubes. It has been observed that introducing the multiwall carbon nanotubes delays the polymerization process as revealed by the modification of the activation energy obtained by differential scanning calorimetry. The viscoelastic response of the nanocomposites was studied from the measurements of storage modulus and the loss factor using dynamic mechanical analysis to evaluate the effect of the interface in each matrix/carbon nanotube system with changing matrix mobility. These measurements provide indications about the increase in the storage modulus of the composites, shift in the glass transition temperature due to the restriction of polymer chain movement by carbon nanotubes. POLYM. COMPOS., 35:441–449, 2014. © 2013 Society of Plastics Engineers     

The effect of graphene nanofiller on the crystallization behavior and mechanical properties of poly(vinyl alcohol)

The effect of graphene on the crystallization behavior of graphene/poly(vinyl alcohol) (PVA) nanocomposites is investigated in terms of the heterogeneous nucleation effect using Fourier transform infrared spectroscopy and differential scanning calorimetry. Nanometer‐sized graphenes with disc‐type shape are successfully fabricated by transversal cutting of platelet carbon nanofibers, and the graphene/PVA nanocomposites are prepared by varying the concentration of graphene using a solution‐casting method. The graphene/PVA nanocomposites exhibit an enhanced degree of crystallization, increasing to 18.8% at a graphene concentration of 0.5 wt%. The graphene acts as an effective nucleating agent during the crystallization process, enhancing the degree and rate of crystallization. In addition, the graphene/PVA nanocomposites with a high graphene content have markedly improved mechanical properties. Mechanical properties, including hardness and elastic modulus, of the prepared graphene/PVA nanocomposites are analyzed using an atomic force microscopy nanoindentation method. The graphene plays a key role in increasing the crystallinity by acting as an effective nucleating agent at low concentrations (<1.0 wt%) and in enhancing the mechanical properties by acting as a nanofiller at high concentrations (>1.0 wt%).     

Synthesis and characterization of multiwall carbon nanotube/waterborne polyurethane nanocomposites

The preparation of thermoplastic nanocomposites of waterborne polyurethane (WBPU) and multiwall carbon nanotubes (MWCNTs) via an in situ polymerization approach is presented. The effects of the presence and content of MWCNTs on the morphology and thermal, mechanical and electrical properties of the nanocomposites were investigated. Carbon nanotubes were modified with amide groups in order to enhance their chemical affinity towards WBPU. Thermogravimetric studies show enhanced thermal stability of the nanocomposites. Scanning and transmission electronic microscopy images prove that functionalized carbon nanotubes can be effectively dispersed in WBPU matrix. Mechanical properties reveal that Young's modulus and tensile strength tend to increase when appropriate amounts of MWCNTs are loaded due to the reinforcing effect of the functionalized carbon nanotubes. Thermal properties show an increase in the glass transition temperature and storage modulus with an increase in MWCNT content. X‐ray diffraction reveals better crystallization of the WBPU in the presence of MWCNTs. The WBPU/MWCNT nanocomposite film containing 1 wt% of MWCNTs exhibits a conductivity nearly five orders of magnitude higher than that of WBPU film. © 2017 Society of Chemical Industry     

Low electrical conductivity threshold and crystalline morphology of single-walled carbon nanotubes - high density polyethylene nanocomposites characterized by SEM, Raman spectroscopy and AFM

The electrical conductivities (σ) of nanocomposites of single-walled carbon nanotubes (SWCNTs) and high density polyethylene (HDPE) have been studied for a large number of nanocomposites prepared in a SWCNT concentration range between 0.02 and 8 wt%. The values of σ obey a percolation power law with an SWCNT concentration threshold, p_c = 0.13 wt%, the lowest yet obtained for any kind of carbon-polyethylene nanocomposites. Improved electrical conductivities attest to an effective dispersion of SWCNT in the polyethylene matrix, enabled by the fast quenching crystallization process used in the preparation of these nanocomposites. Characterization by scanning electron microscopy (SEM) and Raman spectroscopy consistently points to a uniform dispersion of separate small SWCNT bundles at concentrations near p_c and increased nanotube clustering at higher concentrations. Near p_c, high activation energies and geometries of long isolated rods suggest that electron transport occurs by activated electron hopping between nanotubes that are close to each other but still geometrically separate. The degree of SWCNT clustering given by Raman spectroscopy and the barrier energy for electrical conductivity are highly correlated. The nanotubes act as nucleants in the crystallization of the polyethylene matrix, and change the type of supermolecular aggregates from spherulites to axialitic-like objects. The size of crystal aggregates decreases with SWCNT loading, however, in reference to the unfilled polyethylene, the three-dimensional growth geometry extracted from the Avrami exponents remains unchanged up to 2 wt%. Consistency between SEM, Raman and electrical transport behavior suggests that the electrical conductivity is dominated by dispersion and the geometry of the SWCNT in the nanocomposites and not by changes or lack thereof in the HDPE semicrystalline structure.     

Tuning the interlaminar shear strength and thermo-mechanical properties of glass fiber composites by incorporation of (3-mercaptopropyl) trimethoxysilane-functionalized carbon black

The incorporation of functionalized nanoscale fillers into traditional glass fiber/unsaturated polyester (GF/UPE) composites provides a more robust mechanical attributes. The current study demonstrates the potential of 3-mercaptopropyl trimethoxysilane (MPTS)-functionalized carbon black (f-CB) for enhancing the thermo-mechanical properties of GF composites. The composites infused with 1, 3 and 5 wt% of pristine and MPTS-functionalized CB were fabricated by hand lay-up and hot press processing. Tensile testing, interlaminar shear strength (ILSS) testing and dynamic mechanical analysis were used to evaluate the performance of nanocomposites. Fourier transform infrared spectroscopy validated the MPTS functionalization of CB. Pristine CB-loaded nanocomposites exhibited marginal improvement in ultimate tensile strength (UTS), ILSS and thermo-mechanical properties. However, with the addition of f-CB, the improvement in all the studied properties was more substantial. The inclusion of 5 wt% f-CB increased the elastic modulus and UTS by 16 and 22%, respectively, whereas the ILSS was enhanced by 36%, in comparison to the neat GF composite. The scanning electron microscope analysis of fractured ILSS samples revealed better fiber-matrix adhesion and compatibility in f-CB-loaded nanocomposites. At the same filler weight percentage, the storage modulus at 25 °C was ~ 19% higher than that of neat composite. The f-CB inclusion resulted in increment of T _g by ~ 13 °C over the T _g of neat GF/UPE composite (~ 109 °C). These improvements were due to the chemical connection of f-CB to the UPE matrix and GF surface. With such improvements in thermal and mechanical properties, these nanocomposites can replace the conventional GF composites with prominent improvements in performance.