A sensitive nanocalorimetric technology based on microcantilever sensors is presented. The tech-
nology, which combines very short response times with very small sample consumption, uses the
bimetallic effect to detect thermal transitions. Specifically, abrupt variations in the Young’s modu-
lus and the thermal expansion coefficient produced by temperature changes have been employed to
detect thermodynamic transitions. The technology has been used to determine the glass transition
of poly(3-thiophene methyl acetate), a soluble semiconducting polymer with different nanotechno-
logical applications. The glass transition temperature determined using microcantilevers coated with
ultra-thin films of mass
C higher than that obtained using a conventional differential
scanning calorimeter for bulk powder samples of mass
g. Atomistic molecular dynamics
simulations on models that represent the bulk powder and the ultra-thin films have been carried out
to provide understanding and rationalization of this feature. Simulations indicate that the film-air in-
terface plays a crucial role in films with very small thickness, affecting both the organization of the
molecular chains and the response of the molecules against the temperature.
CitacióAhumada, Ó. [et al.]. Sensitive thermal transitions of nanoscale polymer samples using the bimetallic effect: Application to ultra-thin polythiophene. "Review of scientific instruments", 15 Juny 2013, vol. 84, núm. 5, p. 1-8.