Crystal growth rate in ultrathin films of poly(ethylene oxide)

Many dynamical properties of polymers, including segmental relaxation and c hain diffusion, exhibit anomalies in thin-film samples. We extend the studi es of thin-film dynamics to the case of semicrystalline polymers and presen t a study of the crystal growth rate for thin films of poly(ethylene oxide) . We used optical microscopy and quartz crystal microbalance techniques to characterize the kinetics of crystallization for films with thicknesses fro m 40 to 1000 nm for a range of temperatures near the melting point. A remar kable slowing down of the crystal growth is observed at all temperatures st udied for films with a thickness of less than similar to 100 nm. The result s can be used to suggest reductions of the mobility of chains at the crysta l/amorphous interface. (C) 2001 John Wiley & Sons, Inc.