Abstract:
:Cellulose acetate (DS = 2.45) was extensively investigated by Circular Dichroism (CD) in acetonitrile and dioxane. We found great differences between the CD spectra of a 1 wt % acetonitrile solution and the corresponding dioxane solution of cellulose acetate (CA) indicating that the macromolecules exist in those solutions in different molecular arrangements (e.g., persistence length, solvatation shell). The resulting morphologies could be transformed reversibly into each other, as we found by measuring the CA in mixtures of both solvents. Solid CA films show discernible CD spectra depending on the solvent they were evaporated from. In this way, we prepared solid films of the same polysaccharide owning different chiral properties. Furthermore, changes in the spectra occurred with increasing CA concentration. Basing upon our findings, some general statements concerning the polymer behavior of CA are possible.
journal_name
Biopolymersjournal_title
Biopolymersauthors
Meissner D,Einfeldt J,Schareina Tdoi
10.1002/(SICI)1097-0282(199908)50:2<163::AID-BIP5>subject
Has Abstractpub_date
1999-08-01 00:00:00pages
163-6issue
2eissn
0006-3525issn
1097-0282pii
10.1002/(SICI)1097-0282(199908)50:2<163::AID-BIP5>journal_volume
50pub_type
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