method for preparing a resin in aqueous solution or colloidal suspension suitable for providing strength in wet condition on paper.process for the manufacture of paper with increased strength in wet condition, and according to this method obtained paper.

摘要

1417015 Polyamides DIAMOND SHAMROCK CORP 13 Dec 1972 [8 Nov 1972] 57501/72 Heading C3R [Also in Division D2] A resin is made by: (A) reacting (I) a polycarboxylic acid or ester or anhydride thereof and (II) a polyamine containing at least 2 primary and at least 1 secondary or tertiary amine groups; (B) removing any water and/or alcohol, (C) reacting the thus-formed polyamide (P) with a polyamine containing only one primary amino group to cap all free carboxylic groups on (P), (D) adding water so as to form a uniform solution, (E) reacting with a C 1-12 dihalide to extend the chain, (F) adding water in amount dependent on the desired final-product concentration and (G) reaching with equimolar quantities of an optionally alkyl-substituted epihalohydrin. (I) is (a) a C 4-12 saturated dicarboxylic acid, (b) a C 5-12 non-dicarboxylating unsaturated dicarboxylic acid, (c) a C 6-10 saturated or non-dicarboxylating unsaturated tricarboxylic acid, a mono- or di-C 1-12 ethyl ester of a C 2-12 saturated or unsaturated dicarboxylic acid, (e) a mono- or di-C 1-12 alkyl ester of a C 6-10 saturated or unsaturated tricarboxylic acid; or (f) an anhydride of a C 4-5 saturated or unsaturated carboxylic acid. 0À66-0À99 Moles (II) are present per mole (I). (A) is performed, optionally in enough water to form a slurry, at 15- 240‹ C. and for 1-20 hrs.; (C) at 70-180‹ C. for “-3 hrs.; (E) at 80-120‹ C. for 1-3 hrs. and (G) at 40-90‹ C. for 20 min, to 15 hrs. In (G) there is 0À6-1À5 moles or epihalohydrin per mole unreacted secondary or tertiary amino group, but not so much that pH is reduced below 5À0. The resin is added to an aqueous suspension of paper stock in the manufacture of high wet-strength paper, there being by wt. 0À1-5À0 parts resin per 100 parts dry pulp. Or the resin may be applied to partially or completely dried paper. The resins exhibit low self-sizing and degrade easily, thus facilitating the recycling of waste paper and broke.