Abstract: Polysaccharide aldehydes having the formula Sacch--O--CH.sub.2 --CH.dbd.CH--CHO, Saach--O--CH.sub.2 --C.tbd.C--CHO, ##STR1## starch, cellulose, and gum aldehydes, are useful for imparting wet, dry, or temporary wet strength to paper. They are prepared by a non-oxidative method which involves reacting the polysaccharide base, in the presence of alkali, with a derivatizing acetal reagent having the general structure ##STR2## and then hydrolyzing the acetal by adjusting the pH to less than 7, preferably 2-4. In the formulas, n is 1-3; R.sup.11 and R.sup.12 are independently an alkyl, aryl, aralkyl, or alkaryl group when n is 1, R.sup.11 or R.sup.12 is one of the groups when n is 2, or R.sup.11 and R.sup.12 are not present when n is 3; R.sup.13 is an alkyl group, optionally containing an ether linkage, or an aralkyl group; R.sup.14 and R.sup.15 are individually a hydrogen or a methyl group; R.sup.16, R.sup.17, and R.sup.18 are individually an alkyl group; Y.sup.

Abstract: Polysaccharide aldehydes having the formula Sacch-O-CH.sub.2 -CH.dbd.CH-CHO, Sacch-O-CH.sub.2 -C.tbd.C-CHO, ##STR1## such as starch, cellulose, and gum aldehydes, are useful for imparting wet, dry, or temporary wet strength to paper. They are prepared by a non-oxidative method which involves reacting the polysaccharide base, in the presence of alkali, with a derivatizing acetal reagent having the general structure ##STR2## and then hydrolyzing the acetal by adjusting the pH to less than 7, preferably 2-4. In the formulas, n is 1-3; R.sup.11 and R.sup.12 are independently an alkyl, aryl, aralkyl, or alkaryl group when n is 1, R.sup.11 or R.sup.12 is one of the groups when n is 2, or R.sup.11 and R.sup.12 are not present when n is 3; R.sup.13 is an alkyl group, optionally containing an ether linkage, or an aralkyl group; R.sup.14 and R.sup.15 are individually a hydrogen or a methyl group; R.sup.16, R.sup.17, and R.sup.18 are individually an alkyl group; Y.sup.

Abstract: Polysaccharide esters containing aldehyde and acetal groups having the structural formulas ##STR1## are prepared by reacting a polysaccharide, such as a starch, gum, or cellulose, with an acetal-containing reagent which contains a functional group reactive with the hydroxyl groups of the polysaccharide; Z is a multivalent organic group; A and A' are independently a lower alkyl or together form at least a 5-membered cyclic acetal; x is at least 1; and y is at least 1. When x is>1 the esters are corsslinked. Typical reagents for introducing the acetal group include 3,3-diethoxypropionyl guanidine (itself a novel compound) and 4-(methylaminoacetaldehyde dimethyl acetal)-4-oxo-butanoic acid). The derivatives are useful in conventional applications such as coatings, adhesives, paper additives and foodstuffs.

Abstract: Polysaccharide esters containing aldehyde and acetal groups having the structural formulas ##STR1## are prepared by reacting a polysaccharide, such as a starch, gum, or cellulose, with an acetal-containing reagent which contains a functional group reactive with the hydroxyl groups of the polysaccharide; Z is a multivalent organic group: A and A' are independently a lower alkyl or together form at least a 5-membered cyclic acetal; x is at least 1; and y is at least 1. When x is >1 the esters are crosslinked. Typical reagents for introducing the acetal group include 3,3-diethoxypropionyl guanidine (itself a novel compound) and 4-(methylaminoacetaldehyde dimethyl acetal)-4-oxo-butanoic acid). The derivatives are useful in conventional applications such as coatings, adhesives, paper additives and foodstuffs.

Abstract: Polysaccharide aldehydes having the formula ##STR1## starch, cellulose, and gum aldehydes, are useful for imparting wet, dry, or temporary wet strength to paper. They are prepared by a non-oxidative method which involves reacting the polysaccharide base, in the presence of alkali, with a derivatizing acetal reagent having the general structure ##STR2## and then hydrolyzing the acetal by adjusting the pH to less than 7, preferably 2-4. In the formula, n is 1-3; R.sup.11 and R.sup.12 are independently an alkyl, aryl, aralkyl, or alkaryl group when n is 1, R.sup.11 or R.sup.12 is one of the groups when n is 2, or R.sup.11 and R.sup.12 are not present when n is 3; R.sup.13 is an alkyl group, optionally containing an ether linkage, or an aryl, aralkyl, or alkaryl group; R.sup.14 and R.sup.15 are individually a hydrogen or a methyl group; R.sup.16, R.sup.17, and R.sup.18 are individually an alkyl group; Y.sup.

Abstract: Polysaccharide aldehydes having the formula Sacch--O--CH.sub.2 --CH.dbd.CH--CHO, ##STR1## such as starch, cellulose, and gum aldehydes, are useful for imparting wet, dry, or temporary wet strength to paper. They are prepared by a non-oxidative method which involves reacting the polysaccharide base, in the presence of alkali, with a derivatizing acetal reagent having the general structure ##STR2## and then hydrolyzing the acetal by adjusting the pH to less than 7, preferably 2-4. In the formulas, n is 1-3; R.sup.11 and R.sup.12 are independently an alkyl, aryl, aralkyl, or alkaryl group when n is 1, R.sup.11 or R.sup.12 is one of the groups when n is 2, or R.sup.11 and R.sup.12 are not present when n is 3; R.sup.13 is an alkyl group, optionally containing an ether linkage, or an aralkyl group; R.sup.14 and R.sup.15 are individually a hydrogen or a methyl group; R.sup.16, R.sup.17, and R.sup.