DIRECT OBSERVATION OF SURFACE-MORPHOLOGY AND SURFACE VISCOELASTIC PROPERTIES OF POLYMERIC SOLIDS BASED ON SCANNING FORCE MICROSCOPY

Scanning force microscopy (SFM) was applied for the studies of the sur face morphology and viscoelastic properties of polymeric solids. Surfa ce morphology of polyethylene (PE) single crystals was studied by atom ic force microscopy (AFM) and friction force microscopy (FFM). The AFM observation revealed the lozenge-shaped single crystals of PE with ri dgy structure. The FFM experiment revealed that the frictional force o n the same sector was dependent on the scanning direction against {110 } for the PE single crystal prepared from fractionated HDPE with Mw = 10 k. On the other hand, the frictional force did not strongly depend on the scanning direction for the PE single crystal prepared from unfr actionated PE with Mw of 520 k. The FFM results revealed the regularit y of chain folding on PE single crystal surface. Nano-mechanical prope rties of phase-separated polymer surface were imaged by scanning visco elasticity microscopy (SVM), which has been developed by the authors. Images of dynamic viscoelasticity for both the immobilized (octadecylt richlorosilane/fluoroalkylsilane) mixed monolayer and [polystyrene(PS) /poly(vinyl methyl ether) (PVME)] blend ultrathin film were presented. SVM could reveal the difference in dynamic viscoelasticity on the pha se-separated polymer surface with a nanometer scale resolution.