Cationic polyurethane compositions, quaternary ammonium salts and methods for their preparation

DETAILED DESCRIPTION The present invention is directed to a method for forming quaternary ammonium salts by reacting a tertiary amine moiety with an excess of an alkylene oxide in a system comprising a strong acid.
More particularly, the present invention provides methods for forming isocyanate reactive quaternary ammonium compounds.
These quaternary compounds are of particular value in the preperation of cationic polyurethanes.
Additionally, the present invention provides methods for the synthesis of novel cationic polyurethanes containing pendent hydroxy alkyl groups from polyurethanes containing tertiary nitrogen groups.
The present invention provides new quaternary ammonium salts.
These compositions are represented by the following formula: ##STR1## wherein R and R' are each independently selected from, in general, alkyl groups having from 1 to about 10 carbon atoms, phenyl, and substituted phenyl groups; the carbon atoms can be linear, in the form of cyclical rings of hydrocarbons or can be heterocyclic; preferably R and R' will be alkyl groups having about 1 to 4 carbon atoms and more preferably R and R' will be methyl or ethyl groups; R" is selected, in general, from hydrogen, alkyl groups having from 1 to about 10 carbon atoms, cycloalkyl groups having from 5 to 7 carbon atoms in the cycloalkyl group and aryl groups; preferably R" is H or methyl; R'" is, in general, selected from hydrogen, methyl, ethyl, phenyl, aryl, and substituted alkyls such as cyano or nitro substituted alkyls and the like; m and n are integers independently selected from 0 to about 15; and, X is the ion of a strong acid, i.
e.
, an acid having a pK.
sub.
a <3 such as F.
sup.
-, Br.
sup.
-, Cl.
sup.
-, SO.
sub.
3.
sup.
-, NO.
sub.
3.
sup.
-, COO.
sup.
- etc.
, with SO.
sub.
3.
sup.
- being preferred.
The quaternary ammonium salts represented by Formula I can be prepared by reacting a tertiary amine with a molar excess of an alkylene oxide having the structural formula: ##STR2## (wherein R" is as previously defined) in the presence of a relatively strong acid