Dynamic mechanical analysis (DMA) is traditionally performed on bulk sample
s. However, studies of polymer blends would be enhanced if DMA could be app
lied on a local scale in order to enable a new form of microthermal analysi
s. Mounting a sample on a vibrating heating stage and observing the resulti
ng amplitude and phase of the motion of an atomic force microscope cantilev
er allows the local elastic and visco-elastic properties to be studied. It
is demonstrated in this article on samples of polyethersulfone/poly (acryon
itrile-co-styrene) and polystyrene/poly(methyl methacrylate) (PS/PMMA) blen
ds, and PMMA, PS and polytetrafluoroethylene homopolymers. Images at a spec
ific temperature and spectroscopic data as a function of temperature of (no
minally) a single point were collected. Primary and secondary relaxations w
ere detected; the lateral resolution is better than 100 nm. We discuss the
promising and limiting aspects of this new technique. (C) 2000 Elsevier Sci
ence Ltd. All rights reserved.