Method for preparing high molecular weight random polyhydroxypolyamides
High molecular weight random polyhydroxypolyamides (PHPAs) are produced by creating prepolymers which are further polymerized. Random prepolymers are formed from a stoichiometrically molar balance (1:1) starting material. The starting material is a 1:1 stoichiometrically balanced esterified aldaric acid:alkylene or alkylene derived diammonium salt. Alternatively, the starting material is an esterified stoichiometrically balanced diacid:diamine salt and a N′-ammoniumalkyl (or alkyl derived)-D-aldaramic acid terminal carboxylate zwitterionic salt mixture. The starting materials are polymerized in a basic alcohol using a second amine. The polymerized material, or the random prepolymers, are isolated and then further polymerized in a solvent, typically a mixed solvent of an alcohol and non-alcohol, to obtain the high molecular weight PHPAs.
1. A method of preparing random polyhydroxypolyamides, the method comprising the steps of:
a) forming a stoichiometrically molar balanced (1:1) aldaric acid:alkylenediamine (or alkylene derived) salt;
b) esterifying the aldaric acid unit of the alkylene or alkylene derived diammonium aldarate with an alcohol comprising an acid catalyst;
c) polymerizing the molar balanced (1:1) esterified aldaric acid:diammonium disalt in basified alcohol to form a random prepolymer; and
d) polymerizing the random prepolymer in a solvent to form the random polyhydroxypolyamide.
2. The method of claim 1 , wherein the following is substituted:
forming a stoichiometrically molar balanced 1:1 aldaric acid:alkylenediamine (or alkylene derived) salt and a N′-ammoniumalkyl (or alkyl derived)-aldaramic acid terminal carboxylate zwitterionic salt mixture, the mixture being then esterified as in b) to the 1:1 esterified aldaric acid:alkylene (or alkylene derived) diammonium salt in mixture with the esterified N-ammoniumalkyl (or alkyl derived)-aldaramic acids, that mixture then being polymerized and postpolymerized as in steps c) and d).