A two-dimensional NMR study of the solution conformation of a nylon-3, poly-alpha-isobutyl L-aspartate (PAIBLA).
23 October 1987
We report a two-dimensional (2D) NMR study on the solution conformation of a nylon-3, poly-alpha- isobutyl L-asparate (PAIBLA). For this material antiparallel beta-sheet and right- and left-handed helices have each been suggested as representing the main chain structure of the polymer in crystalline form and in chloroform solution. Experimental results are compared to those expected for all three structures. The beta-sheet array implies equal distances between amide (NH) and each methylene (CH sub 2 proton, in marked contrast with experiment. An analysis of the experimental points indicates that the actual structure may be a modification of the right-handed helix.