A quantitative study of the volume changes resulting from pressure-induced unfolding of m-phenylene ethynylene foldamers in solid PMMA and PtBMA

Zhu A; Mio MJ; Moore JS; Drickamer HG

Chemical Physics Letters, Vol.342, No.3-4, 337-341, 2001

DOI10.1016/S0009-2614(01)00587-5 Export Citation

A quantitative study of the volume changes resulting from pressure-induced unfolding of m-phenylene ethynylene foldamers in solid PMMA and PtBMA

Zhu A, Mio MJ, Moore JS, Drickamer HG

We have measured the change of the equilibrium constant with pressure for four foldamers of m-phenylene ethynylene. From the change in ln K over short pressure intervals, we have extracted the change in partial molar volume vs pressure in polymethylmethacrylate (PMMA) and polytertbutylmethacrylate (PtBMA). For a given foldamer the ratio of Delta(V) over bar' in the two media is larger for shorter oligomers. The effect of replacing hydrogen by CH3 in the foldamer is greater in PMMA than in PtBMA. In a given medium, the Delta(V) over bar' per monomer unit is essentially independent of the chain length.