Nanocomposites have been accepted as a great benefit in the nanotechnology field as combining two different materials enhances the deficient characteristics of a particular material, promoting their attractive features. As a result, the best properties of the two components can be extracted to meet the required material applications.
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What is Nanocomposite?
Nanocomposites are composites formed by combining two or more materials, one of which is a nanomaterial, such as carbon nanotubes and graphene. The resulting material has synergistic benefits of both materials with improved thermal stability, mechanical properties, such as bulk properties, strength, withstand limits, electrical conductivity, chemical resistance, and optical clarity.
Based on the amount of polymeric material in the composite, nanocomposite materials may be classed as polymer-based and non-polymer-based.
With their ability to tolerate stress and severe temperatures, nanocomposites have attracted great interest in research and development. They are the preferred choice in a wide range of applications, from electronics to food packaging to automotive to sporting goods. However, exploiting nanocomposites to an appropriate application depends on the material properties. Therefore, characterizations of nanocomposites are important to understand the applicability of materials in the field of nanotechnology-related industrial strategies.
Due to the nature of nanocomposites, excessive thermal stresses can cause heat transfer-related issues, such as inconsistent temperature distribution, nonlinear temperature gradient, and improper heat exchange between the desired samples and the environment. This makes thermal analysis (TA) a significant analysis to understand the properties of nanocomposites.
Understanding Thermal Analysis
First introduced by Le Chatelier in 1887, TA is a technique commonly used for analyzing the time and temperature that enact physical changes of a sample or a material once heated or cooled.
Commonly valuable for investigating different properties of a material, a wide range of techniques are available depending on the purpose.
The technique can be applied to gain further insight into the structure of nanocomposites. Mostly, scientists adopt this technique to study the decomposition reactions of materials to determine the characteristics of volatilization and kinetic parameters, such as the activation energy and the influence of temperature and heating rate on the development of thermal decomposition and reaction mechanisms.
The technique is also commonly used to measure the pore diameters of polymer matrix structure and to understand the internal nanostructure before and after combustion. For example, studies have sought to understand the properties of nylon matrix and demonstrated that introducing glass fiber and nanoclay into nylon matrix increases thermal stability.
Some of the commonly used thermal analyses that have become complementary techniques useful for characterization nanocomposites or nanomaterials are Differential Scanning Calorimetry (DSC), Differential Thermal Analysis (DTA), Thermo Gravimetric Analysis (TGA), Thermo Mechanical Analysis (TMA).
Use of Thermal Analysis for Nanocomposite Analysis
Jayanarayanan, Rasana, and Mishra (2017) wrote a chapter in a book ‘Thermal and Rheological Measurement Techniques for Nanomaterials Characterization’ about dynamic mechanical thermal analysis in characterizing polymer nanocomposites.
The study demonstrates the modifications in the viscoelastic behavior of the polymers with the inclusion of nanofillers. The macromolecular relaxation of the polymer was characterized concerning the temperature and loading frequency.
Another research team measured the degradation of the polyurethane and confirmed that it occurs between the temperature 200-400°C. Below 190°C, the weight loss of the materials was observed, which is attributed to volatile compounds and impurities embedded in the surface of the polyurethane.
In another research, synthesized graphene oxide–glycine (GO–G) nanocomposite in ethanol solvent. They confirmed the formation of nanocomposite was due to the reaction between GO and G.
For the characterization, TGA was employed, which showed that the thermal stability of GO was more than that of the GO–G nanocomposite. Recently, (Farha, Al Naim, & Mansour, 2020) investigated the thermal degradation of polystyrene/ZnO nanocomposites by using sol-gel prepared ZnO nanorods as nanofillers.
Thermal degradation of the samples was checked using TGA and DSC under non-isothermal conditions and a constant heating rate of 10°C min. Their research showed that the thermal stability of the nanocomposite enhanced due to the addition of the ZnO nanoparticles.
Future of Thermal Analysis for Nanocomposite Analysis
The nanotechnology field will continue to grow in the coming years, craving enormous research and innovation, notably in the application of nanocomposites. Therefore, synthesizing and designing materials that possess good thermal characteristics is crucial for multifunctional applications of nanocomposites.
Although some researchers have presented insensitivity and higher standard deviation as a current limitation of the technique, better processing conditions and an appropriate choice of technique for a required purpose still make TA an important contributing factor in developing nanocomposite.
Continue reading: Investigating Graphene Nanomaterials with Thermogravimetric Analysis
References and Further Reading
Najafi, F., & Rajabi, M. (2015). Thermal gravity analysis for the study of stability of graphene oxide–glycine nanocomposites. International Nano Letters. doi:10.1007/s40089-015-0154-7
Bhagyaraj, S., Oluwafemi, O., Kalarikkal, N., & Thomas, S. (2018). Characterization of Nanomaterials: Advances and Key Technologies. Woodhead Publishing. doi:10.1016/C2016-0-01721-7
Bogue, R. (2011). Nanocomposites: a review of technology and applications. Assembly Automation. doi:10.1108/01445151111117683
Corcione, C. E., & Frigione, M. (2012). Characterization of Nanocomposites by Thermal Analysis. Materials. doi:10.3390/ma5122960
Farha, A., Al Naim, A., & Mansour, S. (2020). Thermal Degradation of Polystyrene (PS) Nanocomposites Loaded with Sol Gel-Synthesized ZnO Nanorods. Polymers. doi:10.3390/polym12091935
Jayanarayanan, K., Rasana, N., & Mishra, R. K. (2017). Chapter 6: Dynamic Mechanical Thermal Analysis of Polymer Nanocomposites. In S. Thomas, R. Thomas, A. Zachariah, & R. K. Mishra, Thermal and Rheological Measurement Techniques for Nanomaterials Characterization. doi:10.1016/B978-0-323-46139-9.00006-2
Mena, M., Estrada, R., Torres, L., Tinajero, R., & Palafox, L. (2018). Characterization of Polymer Nanocomposites with Thermal Analysis and Spectrum techniques. TechConnect Briefs.
Moseson, D., Jordan, M., Shah, D., Corum, I., Alvarenga Jr., B., & Taylor, L. (2020). Application and limitations of thermogravimetric analysis to delineate the hot melt extrusion chemical stability processing window. International Journal of Pharmaceutics. doi:10.1016/j.ijpharm.2020.119916
Mourdikoudis, S., Pallares, R., & Thanh, N. (2018). Characterization techniques for nanoparticles: comparison and complementarity upon studying nanoparticle properties. Nanoscale. doi:10.1039/C8NR02278J
Pashaei, S., Siddaramaiah, S., Avval, M., & Syed, A. (2011). Thermal degradation kinetics of nylon6/GF/crysnano nanoclay nanocomposites by TGA. Chemical Industry and Chemical Engineering Quarterly. doi:10.2298/CICEQ101007064P
Ray, S., & Cooney, R. (2018). Chapter 9 - Thermal Degradation of Polymer and Polymer Composites. In M. Kutz, Handbook of Environmental Degradation of Materials (Third Edition). William Andrew. doi:10.1016/B978-0-323-52472-8.00009-5
Sen, M. (2020). Nanotechnology and the Environment. doi:10.5772/intechopen.93047