Polysaccharide aldehydes having the formula ##STR1## or Sacch--O--CH.sub.2 --Ar--CHO (II) such as starch, cellulose, and gum aldehydes, are useful as paper additives for imparting strength and as the granular or gelatinized portion of a corrugating adhesive. Those having formula I are prepared by a nonoxidative 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 Ar is an aryl group, optionally containing an ether linkage, or an alkaryl group and A and A' are lower alkyls or together form at least a 5-membered cyclic acetal. The polysaccharide aldehydes are crosslinked by the addition of selected polyfunctional crosslinkers such as an aliphatic primary polyamine or polyketone.
具有以下式子的
多糖醛类化合物 ##STR1## 或 Sacch--O--CH.sub.2 --Ar--CHO (II),例如淀粉、
纤维素和
胶醛,可用作造纸添加剂以增强强度,并用作瓦楞纸粘合剂的颗粒或凝胶化部分。式子I的化合物通过非氧化方法制备,该方法涉及在碱的存在下,使用具有一般结构的衍生
乙缩醛试剂与
多糖基反应,然后通过将pH值调整到小于7,优选为2-4,
水解
乙缩醛来制备。在该式中,Ar是芳基或含有醚键的芳基基团,或是烷基芳基基团,A和A'是低烷基或共同形成至少一个5元环
缩醛。通过添加选择的多功能
交联剂,例如脂肪族一级
多胺或多酮,可以交联
多糖醛类化合物。