The alternating copolyamide, poly(L-alanyl-11-aminoundecanoic acid), h
as been synthesized by the active ester method, and subsequently chara
cterized. The structure and morphology of lamellar crystals have been
investigated by using transmission electron microscopy, selected-area
electron diffraction and X-ray diffraction. Additional data have been
obtained from uniaxially oriented fibres. The deduced unit cell parame
ters (a = 4.79, b = 10.35, c = 29.8 Angstrom, and alpha = beta = gamma
= 90 degrees) and the C222(1) space group symmetry indicate a layered
structure which is related to that found in poly(L-alanine). A folded
conformation is also deduced for the polymethylene segment. Results o
btained from enzymatic degradation are also reported. Copyright (C) 19
96 Elsevier Science Ltd.