Preparation of polyvinylamide cellulose reactive adducts

Patent metadata

Field	Value
Publication number	US-9879381-B2
Application number	US-201414546068-A
Country	US
Kind code	B2
Filing date	Nov 18, 2014
Priority date	Dec 6, 2011
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

The present disclosure is directed to a continuous process for preparing cellulose reactive adducts of polyvinylamide.

First claim

What is claimed:

1. A method for preparing a glyoxalated polyvinylamide adduct using a continuous process comprising:
(1) determining a desired constant reaction rate based on extent of glyoxalation reaction and reaction time;
(2) determining a linear relationship between reaction solution pH and reaction temperature for the desired constant reaction rate;
(3) continuously reacting a substantially aqueous reaction mixture of (a) a vinylamide polymer formed from acrylamide monomer and diallyldimethylammonium halide monomer and (b) glyoxal, at a temperature of about 4° C. to about 40° C. and a reaction pH set point of about 9.0 to about 11.5, for about 2 minutes to about 200 minutes,
wherein:
i) the temperature of incoming water is continuously measured;
ii) based on the linear relationship determined in step 2 , the pH of the reaction mixture is continuously adjusted to maintain approximately the desired constant reaction rate;
iii) between 20% and 75% of the glyoxal is consumed, and the molar ratio of the amide functionality on the vinylamide polymer to glyoxal is between 6 to 1 and 2 to 1; and
iv) the concentration of the vinylamide polymer prior to and during formation of the adduct is about 0.5 wt.% to 6 wt.% vinylamide polymer based on the mass of the total reaction mixture, thereby forming the adduct.

2. The method of claim 1 , wherein the adduct is prepared at a temperature of about 4° C. to about 30° C. and a pH of about 9.0 to about 11, and a reaction time of about 2 to 150 minutes.

3. The method of claim 1 , wherein the concentration of the vinylamide polymer prior to and during formation of the adduct is about 0.5 wt. % to 3.5 wt. % vinylamide polymer.

4. The method according to claim 3 , wherein the vinylamide polymer has an average molecular weight of about 50,000 to about 1,000,000 Daltons, prior to the reaction.

5. The method of claim 1 , wherein at least about 40% of the glyoxal is consumed.

6. The method according to claim 1 , wherein the glyoxalated polyvinylamide adduct is a water-soluble thermosetting resin.

7. The method according to claim 1 , wherein the vinylamide polymer is formed from at least 50 wt.% acrylamide monomer based on the total weight of monomers charged to form the vinylamide.

8. The method according to claim 1 , wherein the vinylamide polymer or the polyvinylamide adduct is linear, crosslinked, chain-transferred, or crosslinked and chain-transferred.

9. The method according to claim 8 , wherein the vinylamide polymer or the polyvinylamide adduct is crosslinked using at least a difunctional monomer selected from the group consisting of methylene bis(meth)acrylamide, triallylammonium chloride, tetraallyl ammonium chloride, polyethyleneglycol diacrylate, polyethyleneglycol dimethacrylate, N-vinyl acrylamide, divinylbenzene, tetra(ethyleneglycol) diacrylate, dimethylallylaminoethylacrylate ammonium chloride, sodium salt of diallyloxyacetic acid, diallyloctylamide, trimethyllpropane ethoxylate triacryalte, N-allylacrylamide, N-methylallylacrylamide, pentaerythritol triacrylate, and combinations thereof.

10. The method according to claim 1 , wherein the vinylamide polymer is formed from at least 50 wt.% acrylamide monomer and at least 0.1 wt.% diallyldimethylammonium halide based on the total weight of monomers charged to form the vinylamide.

11. The method according to claim 1 , wherein the vinylamide polymer has an average molecular weight of about 5000 to about 5,000,000 Daltons, prior to the reaction.

12. The method according to claim 1 , wherein adduct formation is monitored by measuring a change in turbidity or viscosity of the aqueous reaction, wherein the change in turbidity results from the adduct formation and the turbidity change is in the range of 0.5 to 500 NTU (nephelometric units).

13. A method of preparing an aqueous cellulosic slurry comprising:
(1) determining a desired constant reaction rate for continuously preparing a glyoxalated polyvinylamide adduct based on extent of glyoxalation reaction and reaction time;
(2) determining a linear relationship between reaction solution pH and reaction temperature for the desired constant reaction rate;
(3) continuously reacting a substantially aqueous reaction mixture of (a) a vinylamide polymer formed from acrylamide monomer and diallyldimethylammonium halide monomer and (b) glyoxal, at a temperature of about 4° C. to about 40° C. and a reaction pH set point of about 9.0 to about 11.5, for about 2 minutes to about 200 minutes to form a glyoxalated polyvinylamide adduct;
wherein:
i) the temperature of incoming water is continuously measured;
ii) based on the linear relationship determined in step 2 , the pH of the reaction mixture is continuously adjusted to maintain approximately the desired constant reaction rate;
iii) between 20% and 75% of the glyoxal is consumed, and the molar ratio of the amide functionality on the vinylamide polymer to glyoxal is between 6 to 1 and 2 to 1; and
iv) the concentration of the vinylamide polymer prior to and during formation of the adduct is about 0.5 wt.% to 6 wt.% vinylamide polymer based on the mass of the total reaction mixture; and

adding the adduct to a papermaking stock to form the aqueous cellulosic slurry.

14. A method of making a paper or board comprising:
(1) determining a desired constant reaction rate for continuously preparing a glyoxalated polyvinylamide adduct based on extent of glyoxalation reaction and reaction time;
(2) determining a linear relationship between reaction solution pH and reaction temperature for the desired constant reaction rate;
(3) continuously reacting a substantially aqueous reaction mixture of (a) a vinylamide polymer formed from acrylamide monomer and diallyldimethylammonium halide monomer and (b) glyoxal, at a temperature of about 4° C. to about 40° C. and a reaction pH set point of about 9.0 to about 11.5, for about 2 minutes to about 200 minutes to form a glyoxalated polyvinylamide adduct;
wherein:
i) the temperature of incoming water is continuously measured;
ii) based on the linear relationship determined in step 2 , the pH of the reaction mixture is continuously adjusted to maintain approximately the desired constant reaction rate;
iii) between 20% and 75% of the glyoxal is consumed, and the molar ratio of the amide functionality on the vinylamide polymer to glyoxal is between 6 to 1 and 2 to 1; and
iv) the concentration of the vinylamide polymer prior to and during formation of the adduct is about 0.5 wt.% to 6 wt.% vinylamide polymer based on the mass of the total reaction mixture; and

applying the adduct to pre-formed paper or board.

Assignees

• Basf Se

Inventors

• Wright Matthew

Classifications

• C08F222/38

  Amides · CPC title

• C08F220/56

  Acrylamide; Methacrylamide · CPC title

• C08F8/28 Primary

  Condensation with aldehydes or ketones · CPC title

• D21H17/375

  Poly(meth)acrylamide · CPC title

• D21H21/20 Primary

  Wet strength agents · CPC title