Structural studies of odd-nylon crystals grown from solution

Research paper by S. Muñoz-Guerra, A. Prieto, J. M. Montserrat, H. Sekiguchi

Indexed on: 01 Jan '92Published on: 01 Jan '92Published in: Journal of Materials Science


Lamellar crystals of nylons 5, 9 and 13 inα-structure were grown from solution and systematically studied by electron microscopy and X-rays. Electron diffraction showed that they all consist of a twinned structure with hydrogen bonds running parallel to the long dimension of the crystals. Polyethylene decoration of such crystals revealed folding sectorization only in the case of nylon 9. Diffraction data from films both uniaxially and biaxially oriented were used to propose a unifying model for theα-structure of odd nylons based on the antiparallel model given by Tadokoro. In this model successive sheets are progressively sheared along the chain axis by approximately twice the interatomic height. Such a model is able to account well for most of the structural observations we have made on solution grown crystals.