Thermosetting creping adhesive with reactive modifiers

1. A creping adhesive composition which is in liquid form comprising a polyamidoamine-epihalohydrin polymer composition comprising a reactive, lightly crosslinked polyamidoamine-epihalohydrin polymer, wherein the polyamidoamine-epihalohydrin polymer composition has at least 0.1% of covalent halogen by weight of polymer solids.

2. The creping adhesive composition of claim 1 wherein the epihalohydrin is epichlorohydrin and the halogen is chlorine.

3. The creping adhesive composition of claim 2 wherein the polyamidoamine-epihalohydrin polymer composition has between 0.1 and 6% of covalent chlorine by weight of polymer solids.

4. The creping adhesive composition of claim 3 wherein the polyamidoamine-epihalohydrin polymer composition has a minimum covalent chloride content of 0.12% by weight of polymer solids.

5. The creping adhesive composition of claim 2 wherein the polyamidoamine-epichlorohydrin polymer composition has a ratio of covalent chlorine to ionic chlorine between 0.01: and 100:1.

6. The creping adhesive composition of claim 5 wherein the polyamidoamine-epichlorohydrin polymer composition comprises a blend of reactive, lightly crosslinked polyamidoamine-epichlorohydrin polymers.

7. The creping adhesive composition of claim 5 wherein the polyamidoamine-epihalohydrin polymer composition comprises a blend of (a) a reactive, lightly crosslinked polyamidoamine-epichlorohydrin polymer and (b) a polymer selected from the group consisting of (i) a polyamidoamine-epichlorohydrin polymer having no covalent chlorine, (ii) a polyamidoamine prepolymer, or (iii) a mixture thereof.

8. The creping adhesive composition of claim 1 wherein the reactive, lightly crosslinked polyamidoamine-epihalohydrin polymer is prepared by reacting (1) a prepolymer of (a) a diacid, or an ester of a diacid, and (b) a polyamide containing secondary or tertiary amine groups with (2) an epihalohydrin, wherein the prepolymer has a weight average molecular weight of 10,000 to 300,000 Daltons.

9. The creping adhesive composition of claim 1 comprising a combination of the polyamidoamine-epihalohydrin polymer composition and a reactive modifier.

10. The creping adhesive composition of claim 9 wherein the reactive modifier has a molecular weight below about 5,000 Daltons and either or both secondary and tertiary amine moieties.

11. The creping adhesive composition of claim 10 wherein the reactive modifier is prepared by reacting a polyalkylenepolyamine with an electrophile.

12. The creping adhesive composition of claim 11 wherein the polyalkylenepolyamine is selected from diethylenetriamine or N-methyl-3,3′-diaminopropylamine.

13. The creping adhesive composition of claim 11 wherein the electrophile is selected from a carboxylic acid, methylene-bis-acrylamide, or urea.

14. The creping adhesive composition of claim 10 wherein reactive modifier solids and polyamidoamine-epihalohydrin polymer composition solids are in a weight ratio in a range of 1000:1 to 1:1.

15. The creping adhesive composition of claim 14 wherein the reactive modifier is a component of a release aid.

16. The creping adhesive composition of claim 1 comprising a plasticizer selected from the group consisting of water soluble polyols, glycols, glycerol, sobitol, polyglycerin, polyethylene glycols, sugars, oligosaccharides, hydrocarbon oils and blends.

17. A creping adhesive composition which is in liquid form comprising a polyamidoamine-epihalohydrin polymer composition comprising a reactive, lightly crosslinked polyamidoamine-epihalohydrin polymer, wherein the polyamidoamine-epihalohydrin polymer composition has at least 0.02% of covalent halogen by weight of polymer solids and wherein the reactive, lightly crosslinked polyamidoamine-epihalohydrin polymer is prepared by reacting (1) a prepolymer of (a) a diacid, or an ester of a diacid, and (b) a polyamide containing secondary or tertiary amine groups with (2) an epihalohydrin, wherein the prepolymer has a weight average molecular weight of 10,000 to 100,000 Daltons.

18. A method of aping cellulosic fiber webs which comprises: a) applying a creping adhesive to a drying surface; b) adhering a cellulosic fiber web to the drying surface; and c) dislodging the web from the drying surface; wherein the creping adhesive comprises a creping adhesive composition of claim 1 .

19. The method of claim 18 wherein the creping adhesive comprises a creping adhesive composition of claim 8 .

20. The method of claim 18 wherein the creping adhesive comprises a creping adhesive composition of claim 9 .

21. The method of claim 18 , wherein the applying step comprises separately applying (1) a creping adhesive comprising the polyamidoamine-epihalohydrin polymer composition and (2) a reactive modifier to the drying surface for combination on the drying surface.

22. The method of claim 21 wherein a release aid also is applied to the drying surface.

23. The method of claim 22 wherein the release aid is selected from an imidazoline base or an oil-based dispersion.

24. The method of claim 23 wherein the imidazoline base comprises a methyl or ethyl sulfate salt of quaternary imidazoline derived from fatty acids.

25. The method of claim 23 wherein the oil-based dispersion comprises paraffinic oil, naphthenic oil, a vegetable oil or a blend thereof.

26. The method of claim 23 wherein the reactive modifier is a component of the release aid.

27. The method of claim 26 wherein the creping adhesive and release aid are applied in a weight ratio of creping adhesive:release aid between 10:90 to 1000:1.

28. The method of claim 22 wherein the creping adhesive and release aid are applied in a weight ratio of creping adhesive:release aid between 10:90 to 1000:1.

29. The method of claim 18 , wherein the applying step comprises applying a mixture of (1) a creping adhesive comprising the polyamidoamine-epihalohydrin polymer composition, (2) a reactive modifier and (3) a release aid to the drying surface.

30. The method of claim 18 , wherein the drying surface comprises a drying surface of a Yankee Dryer.

31. The method of claim 18 , wherein the drying surface comprises a drying surface of a TAD process.

32. The method of claim 18 wherein the polyamidoamine-epihalohydrin polymer composition is applied to the dryer surface in an amount from 0.01 lb/ton to 2.2 lb/ton based on the dry weight of the polymer and the dry weight of the cellulosic fiber being creped.

33. The method of claim 18 wherein the cellulosic fiber web has a content of recycled fibers of up to 100%.

34. The method of claim 18 wherein the cellulosic fiber web has a moisture content ranging from about 5% to about 85% by weight.