Method for preparing hydrophobically-terminated polysaccharide polymers and detergent compositions comprising the polysaccharide polymers

A process for preparing polysaccharide polymers, the process comprising:

• (a) mixing together, in water and in the absence of a cosolvent,
• (i) a polysaccharide represented by structure (I);
• ##STR7## wherein, R.sup.1 is H or is represented by structure I(a) ##STR8## R.sup.2 is H, or is represented by structure I(a) or structure I(b) ##STR9## wherein R.sup.1' is H or is represented by structure I(a),
• R.sup.2' is H or is represented by structure I(a) or structure I(b),
• R.sup.1 and R.sup.2 are not both H, and
• the average of (.SIGMA.m+.SIGMA.n) is greater than or equal to 3;
• and
• (ii) an amine selected from the group consisting of R.sup.3 NH.sub.2, where R.sup.3 is selected from the group consisting of a C.sub.1 -C.sub.3 alkyl group, H or NH.sub.2, thereby producing an aqueous admixture of the polysaccharide and the amine,
• (b) contacting the aqueous admixture of the polysaccharide and the amine with hydrogen, under pressure, in the presence of a Group VIIIB metal catalyst and under conditions effective to produce an N-substituted amino polysaccharide of structure (II);
• ##STR10## (c) adding to the N-substituted amino polysaccharide a reagent which is terminated with one of an amine-reactive functionality selected from the group consisting of a monocarboxylic acid chloride, isocyanate, chloroformate, mixed or symmetric anhydrides of carboxylic acids, epoxide, primary alkyl halide, primary alkyl sulfonate, primary alkyl sulfate, methylene beta-lactone and alkenyl succinic anhydride;
• and
• (d) mixing the N-substituted amino polysaccharide and the reagent under conditions effective to produce a polysaccharide polymer of structure (III), ##STR11## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.1' and R.sup.2' are as above,
• R.sup.4 represents from 1 to 50 independently selected alkyleneoxy groups or is absent,
• R.sup.5 is a phenylene linkage or is absent,
• R.sup.6 is H, or a C.sub.1 -C.sub.24 alkyl group, or the residue of a C.sub.8 -C.sub.20 alkenyl succinic anhydride, provided that;
• when R.sup.5 is absent and R.sup.6 represents H or contains not more than 4 carbon atoms, then R.sup.4 must contain an alkyleneoxy group with at least 3 carbon atoms;
• when R.sup.4 is absent, R.sup.6 is not H;
• and when R.sup.4 and R.sup.5 are absent, then R.sup.6 must contain at least 5 carbon atoms, L is the residue of the amine-reactive functionality, and the average of (.SIGMA.m+.SIGMA.n) is greater than or equal to 3;
• wherein excess amine and the catalyst are removed from the reaction.