Production and properties of highly oriented polyoxymethylene by die-drawing



Highly oriented monofilaments were produced by a high-temperature die-drawing process followed by tensile drawing. It was shown that a successful high-speed process required high-quality melt-extruded rod. The mechanical properties and structure of the die-drawn products were investigated by means of tensile and bending tests, dynamic mechanical measurements, DSC, and X-ray diffraction. The bending modulus and the tensile strength increased with increasing draw ratio. It was also observed that at high draw ratios the γ-dispersion peak in the dynamic mechanical tan δ curve, which is associated with main chain micro-Brownian motion in the amorphous regions, diminishes, implying that these chains become taut. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1268–1278, 2003