Synthesis and Structure of a New Polyalcohol

Abstract

A new polyalcohol is prepared by reduction of the perfectly alternating ethylene−carbon monoxide copolymer. The low melting temperature of this atactic material (137 °C) is attributed to the 1,4-arrangement of the hydroxyl side groups. The different orientations of these slightly bulky groups with respect to the molecular plane give rise to less efficient packing of the chains in the crystal lattice. The reflections in the X-ray diffraction pattern are indexed on the basis of an orthorhombic lattice. The derived unit cell dimension are a = 8.78 A, b = 5.47 A, and c = 7.47 A, and the crystalline density (1.08 g/cm3) is significantly less than the crystalline density of atactic poly(vinyl alcohol) (1.35 g/cm3), which has a 1,3-arrangement of the hydroxyl substituents. Solution cast polyalcohol films could be drawn at 110 °C to a ratio of about 10; a tensile strength of 0.5−0.6 GPa and a (maximum) tensile modulus of 11 GPa are attained.