Review on Thermomechanical Anlysis of Nano Composites

Abstract

A Thermo-Mechanical Analysis (TMA) technique is used to investigate the compatibility & suitability of materials, physical & mechanical characteristics of materials and its optimum processing conditions. It measures the dimensional changes of a sample as a function of time, temperature and force in a controlled atmosphere. This TMA is used to access the glass transition temperature�� ��, melting point temperatures, coefficient of thermal expansion (CTE), deformations and viscoelastic measurements. It can be seen that polymers (ex: glass fibres) expand linearly at relatively low temperatures and gradually develops a varying expansion rate at high temperatures. Further increase of temperature eventually leads to an abrupt change in length at glass transition region (�� ��). In this paper investigation on thermal behaviors of glass fibers, polypropylene/ calcium carbonate nano composite and Nanosilica Reinforced PEEK Composites are presented. Keywords: Thermo Mechanical Analysis, Probes, Nano Composites, Coefficient of thermal expansion, Glass transition temperature. I. Introduction The study of relationship between a sample property and its temperature as the sample is heated or cooled in a controlled manner is referred to as Thermal Analysis (TA). The main TA techniques used for thermal characterization of the matrix resin compositions, composites and their raw materials are Differential Thermal Analysis(DTA), Differential Scanning Calorimetry (DSC), Thermo Gravimetric Analysis (TGV), Thermo Mechanical Analysis (TMA) and Dynamic Mechanical Thermal Analysis (DMTA). Among this TMA is the most important characterization technique in the field of Thermal Analysis (TA). With TMA, sample dimensional properties are measured as the sample is heated, cooled or held under various boundary conditions. The force applied to the sample can be varied with TMA. This technique is used to access the properties of polymers like softening temperature (�� ��), melting temperature, stress relief effects at �� ��, coefficient of thermal expansion(CTE), dimensional capabilities of two or more different materials, composite de lamination temperatures, shrinkage forces, testing of coatings on metals, films, optical fibers and electrical wires .The measurements can be carried out by the number of different probe configurations. Depending on the applied load experiments may be done in compression, tension, shear, torsion, penetration or some bending mode etc.