CHARACTERIZING SPIN FINISH LAYERS ON POLYPROPYLENE FIBER SURFACES BY MEANS OF SCANNING FORCE MICROSCOPY TECHNIQUES

For a better understanding of the structure, distribution, and composi tion of spin finish layers on fiber surfaces, scanning force microscop y techniques are used to image spin finish layers on polypropylene fib er surfaces with submicrometer resolution. The polypropylene staple fi bers are made into nonwovens, and common antistatic, wetting, and hydr ophobizing agents are the spin finishes. Distribution and thickness pr ofiles of the wax-like antistatic and hydrophobizing agents are succes sfully measured with contact mode atomic force microscopy and lateral force microscopy. Nanometer Scale measurements of local adhesion force s and elastic moduli of the spin finish layer surfaces by force modula tion techniques (pulsed force mode) provide further information on the distribution and composition of the spin finish layers. In addition, the oil-like wetting agent layer, which is too soft and sticky for con tact mode measurements, can be imaged with the pulsed force mode techn ique.