Structural studies of poly[(2S,3S)-2,3-dimethoxybutylene alkanamide]s

The structural characterization of a series of stereoregular polyamides 4,n (n=8, 10, 12), which were obtained from polycondensation of (2S,3S)-2,3-dimethoxy-1,4-butanediamine with aliphatic dicarboxylic acids, has been carried out. X-ray diffraction of powder and fiber samples were analyzed together with electron diffraction patterns of single crystals obtained by isothermal crystallization in solution. Experimental results based on lattice parameters data were used to build a preliminary crystal model using the Cerius program. The main characteristic of the proposed model is the presence of intermolecular hydrogen bonds along the crystal a direction, similarly arranged to conventional nylons.