| A micromechanical technique has been used to determine the glass transition temperature of a polymer using gold coated microcantilevers. Polymers have been coated onto the microcantilevers using the microprocessor controlled nano injector. Polymers on the microcantilever have been thermally excited to a temperature greater than their glass transition at a rate of 5°C/min and have been cooled down in an inert nitrogen gas environment. The deflection of the free end of the cantilever due to surface stress on one of its sides is measured during the excitation process. A gradual change in the slope has been noticed around the glass transition temperature. Reproducible results have been obtained by repeating the thermal excitation process with polymer coatings on different microcantilevers. Three polymers poly (acrylic acid) (PAA), poly (hydroxyethyl methacrylate) (PHEMA) and ethyl cellulose (EC) have been tested using this process. |
