hydroxyalkyl galactomannan polymers are obtainable as substituted derivatives of the hydroxy c 1 c 4 alkyl galactomannans which include 1 hydrophobically modified hydroxyalkyl galactomannans e g c 1 c 24 alkyl substituted hydroxyalkyl galactomannans e g wherein the amount of alkyl substituent groups is preferably about 2 by weight or less of the hydroxyalkyl galactomannan and 2 poly oxyalkylene grafted galactomannans see e g a bahamdan amp w h daly in proc 8th polymers for adv technol int 39 l symp budapest hungary september 2005 peg and or ppg grafting is illustrated although applied therein to carboxymethyl guar rather than directly to a galactomannan poly oxyalkylene grafts thereof can comprise two or more than two oxyalkylene residues and the oxyalkylene residues can be c 1 c 4 oxyalkylenes mixed substitution polymers comprising alkyl substituent groups and poly oxyalkylene substituent groups on the hydroxyalkyl galactomannan are also useful herein in various embodiments of substituted hydroxyalkyl galactomannans the ratio of alkyl and or poly oxyalkylene substituent groups to mannosyl backbone residues can be about 1 25 or less i e with at least one substituent per hydroxyalkyl galactomannan molecule the ratio can be at least or about 1 2000 1 500 1 100 or 1 50 or up to or about 1 50 1 40 1 35 or 1 30 combinations of galactomannan polymers according to the present disclosure can also be used as used herein galactomannans comprise a polymannose backbone attached to galactose branches that are present at an average ratio of from 1 1 to 1 5 galactose branches mannose residues preferred galactomannans comprise a 1 u2192 4 linked u03b2 d mannopyranose backbone that is 1 u2192 6 linked to u03b1 d galactopyranose branches galactose branches can comprise from 1 to about 5 galactosyl residues in various embodiments the.