On the phase B of comb-like poly(alpha-alkyl-beta-L-aspartate)s: A simulation of the solubility of small penetrants

Full Paper: The structure and thermal properties of the phase B of poly(alp ha -alkyl-beta -L-aspartarte)s, abbreviated PAALA-n (n being the number of carbon atoms in the linear alkyl side chain), with n = 14 and 16 were deter mined using X-ray diffraction and DSC methods, respectively. These data tog ether with those previously reported by us for the dodecyl derivative were used to perform Monte Carlo simulations of these comb-like polymers. The al lowed to predict the solubility of different gases phase B of PAALA-n. The variation of both the unoccupied space and the excess chemical potential wi th the size of the penetrant were computed. An attractive interaction betwe en the polymer matrix and the penetrants was found when small gases were co nsidered. The results been compared with those recently obtained for crysta lline poly(alpha -alkyl-beta -L-aspartate)s bearing short linear alkyl side chains. Unoccupied space for He penetrant in one of the microstructures generated f or the phase B of PAALA-16. [GRAPHICS]