Abstract
Polyhydroxypolyamides (PHPAs) represent a class of synthetic polyamides derived from aldaric acid and diamine monomer units. This paper describes the synthesis of some poly(galactaramides), a class of polyhydroxypolyamides, that employs alkylene and substituted alkylenediammonium galactarate salts, with 1:1 molar equivalency of the diacid and diamine monomer components, as precursors for the polyamides. The salts were treated with acid/alcohol and then base in order to initiate the polymerization in methanol. The polyamides, labeled as prepolyamides, precipitated from solution and were then subjected to a second polymerization (postpolymerization) in a different solvent to produce a generally larger polyamide, labeled as a postpolyamide.
ACKNOWLEDGMENTS
Significant financial support for this research was from the U.S. Department of Agriculture (USDA-CREES Grant Nos. 2004-364463, 2005-34463-11561, and 2006-34463-16886) and is gratefully acknowledged.
Notes
a In D2O referenced to t-BuOH at 1.203 ppm.
b Insoluble in any suitable NMR solvent.
a In DMSO-d 6 referenced to TMS at 0.00 ppm.
a In TFA-d referenced to residual TFA at 11.50 ppm unless otherwise indicated.
b In D2O referenced to t-BuOH at 1.203 ppm.
c Very broad multiplet.
d Split in D2O but becomes a singlet on addition of base.
e In DMSO-d 6 referenced to TMS at 0.00 ppm.
a Determined by NMR in TFA-d.
b Determined by NMR in D2O.
c Too great to be determined by this method.
d Determined by NMR in DMSO-d 6.