KR100574146B1 - Wet strength agent and method for production thereof - Google Patents

Abstract

The present invention provides a first step of reacting a nitrogen containing polymer with a hydrophobic compound to provide a saturated hydrophobic side chain substituent on the nitrogen containing polymer, a second step of reacting the obtained product with a crosslinking agent to form a cationic wet-strength resin. A method for preparing a paper wet-strength enhancer comprising a third step of emulsion polymerizing one or more ethylenically unsaturated monomers in the presence of a wet-strength resin. The present invention also relates to wet-strength resins and reinforcing agents. The invention also relates to a process for producing paper, in particular tissue paper, using said resins and reinforcing agents in cellulose suspensions, and to papers, in particular tissue papers, containing wet-strength resins and reinforcing agents.

Description

Wet-strength enhancer and its manufacturing method {WET STRENGTH AGENT AND METHOD FOR PRODUCTION THEREOF}

The present invention relates to a paper wet-strength enhancer and a method for producing the same. The invention also relates to a papermaking method comprising the step of adding a paper wet-strength enhancer to an aqueous cellulose suspension and a paper comprising a paper wet-strength enhancer. The present invention further relates to the use of paper wet-strength enhancers as additives to aqueous cellulose suspensions.

In papermaking, wet-strength enhancers such as epichlorohydrin base resins, such as polyaminoamide epichlorohydrin resins, have long been used to enhance the strength of paper. Such resins are disclosed in US 3,700,623 and US 3,772,076. The wet-strength of paper relates to its ability to withstand tearing, tearing and tearing and to maintain physical integrity, especially during use under wet conditions. Another important property of wet-strengthened paper is softness, especially in tissues. Softness is the tactile sensation you feel when you rub paper against your skin.

US 5,200,036 discloses a wet-strength enhancer to enhance the paper's wet-strength. Cationic polyaminoamide epichlorohydrin resins are modified by introducing a polymerizable unsaturated hydrocarbon moiety to provide an ethylenically unsaturated side chain substituent. This resin is introduced into the latex forming monomer and copolymerization occurs to form a bond between the polymerizable unsaturated hydrocarbon portion of the resin and the latex forming monomer. Emulsifiers are added to obtain a suspension of the latex particles formed. Resin of the type mentioned above is also used as an emulsifier. It is usually used in combination with additional compounds as the resin is not sufficiently effective when used as the sole emulsifier.

US 5,314,721 discloses a process for preparing vinyl polymer dispersions comprising resins based on cationic polyaminoamides whose terminal groups have at least 7 carbon atoms and are substituted with long-chain aliphatic hydrocarbon radicals derived from mono carboxylic acids. The product obtained is used as a sizing agent.

US 4,416,729 discloses contacting a linear polyamidoamine with an α, β-ethylenically unsaturated carboxyl compound to form a substituted polyamidoamine and contacting the substituted polyamidoamine with a polyamine to give a branched polyamidoamine having an accessory amine group. And forming a curable accessory ammonium moiety on the branched polyamidoamine by contacting the branched polyamidoamine with epihalohydrin. US 4,416,729 does not disclose the use of wet-strength additives for making tissue paper.

Although epichlorohydrin based resins have suitable wet-strength and emulsifying properties in some applications, it would be desirable to be able to provide improved species wet-strength additives and methods of preparation. It would also be desirable to provide wet-strength resins and additives with improved softness. It would be desirable to provide a resin with further improved emulsifying properties.

In accordance with the present invention it has been found that the paper wet-strength enhancer is improved by a composition containing hydrophobic hydrocarbon groups and polymer particles which provide side chain substituents on the wet-strength resin. Such wet-strength resins and methods of making reinforcements have also been found. It has also been found that the wet-strength resins and reinforcing agents prepared according to the method of the invention provide enhanced softness to the paper without adversely affecting the absorbency.

In particular, the present invention relates to a wet-strength additive comprising a cationic nitrogen-containing polymer having saturated hydrophobic side-chain substituents and a paper wet-strength additive comprising polymer particles. The present invention provides a first step of reacting a nitrogen containing polymer with a hydrophobic compound to provide a saturated hydrophobic side chain substituent on the nitrogen containing polymer, a second step of reacting the obtained product with a crosslinking agent to form a cationic wet-strength resin. A method for preparing a paper wet-strength enhancer comprising a third step of emulsion polymerizing one or more ethylenically unsaturated monomers in the presence of a wet-strength resin. The present invention also relates to a method for producing a new wet-strength resin and to a wet-strength resin produced according to the first two steps mentioned above. The present invention also relates to a papermaking method comprising the step of adding a paper wet strength resin or reinforcing agent to the cellulose suspension and the use of paper wet strength resin or reinforcing agent for paper manufacture. The invention also relates to paper comprising paper wet-strength resins or reinforcing agents.

The present invention provides resins and agents that have the ability to impart improved wet-strength properties to paper. The present invention also provides a simple, convenient and effective route for making paper wet-strength resins or reinforcing agents.

The present invention provides a paper wet-strength resin or reinforcing agent which enables the production of paper with improved softness. The softness of the paper sheet is estimated by means of the relative humidity-intensity value defined as the ratio between the wet-tensile index and the dry-tensile index according to the formula RWS (%) = (WS / DS) · 100, where RWS is the relative humidity. -Strength and WS is wet-tension index DS is dry-tension index. Therefore, RWS is a degree of softness, the higher the RWS, the softer the paper. Wet-strength resins or reinforcing agents of the present invention provide improved emulsifying properties and can be used as sole emulsifiers without additional compounds that may result in undesirable foaming.

"Wet-strength enhancer" refers to an agent that can impart greater wet-strength compared to paper that does not contain such enhancer. Wet-strength enhancers include wet-strength resins. "Wet-strength resin" refers to a resin that can impart greater wet-strength compared to paper that does not contain such a resin.

The method for preparing a paper wet-strength enhancer is a first step of reacting a nitrogen-containing polymer with a hydrophobic compound to provide a saturated hydrophobic side chain substituent in the nitrogen-containing polymer, and reacting the obtained product with a crosslinking agent to form a cationic wet-strength resin. A second step, a third step of emulsion polymerizing the at least one ethylenically unsaturated monomer in the presence of the formed wet-strength resin. According to one embodiment, polyamines having two or more secondary or primary amine groups added between the first and second steps or added after the second step are not reacted.

Nitrogen containing polymers are especially polyaminoamides, polyamines or other nitrogen containing polymers. Preference is given to polyaminoamides which can constitute the reaction product of polycarboxylic acids, in particular dicarboxylic acids and polyamines. "Carboxylic acid" includes carboxylic derivatives such as anhydrides and esters. Suitable polycarboxylic acids include saturated or unsaturated aliphatic or aromatic dicarboxylic acids. Preference is given to polycarboxylic acids containing less than 10 carbons. Suitable polycarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid and derivatives thereof. Mixtures of these compounds may be applied. Suitable polyamines include polyalkylene polyamines such as diethylenetriamine, triethylenetetraamine, tetraethylenepentaamine, dipropylenetriamine. Polyaminoamides prepared according to the method of EP 802 215 A1 can also be used. The molecular weight of the nitrogen containing compound is 100-50000, in particular 500-10000. The ratio of polyamines to polycarboxylic acids is 0.49: 1-1.49: 1, in particular less than 1.3: 1, such as 1.3: 1-0.7: 1. In particular, diethylenetriamine and adipic acid react to form polyaminoamides.

Hydrophobic compounds used include carboxylates or derivatives thereof. The hydrophobization reaction between the nitrogen containing polymer and the hydrophobic compound is carried out through alkylation, vinyllog addition or other reactions. The vinyllog addition reaction is illustrated by the following scheme;

Wherein VVV-NH-VVV is a nitrogen-containing polymer and C = C-COOR is a vinyl group-containing hydrophobic compound. Vinyl groups, ie C = C groups, of hydrophobic compounds can react with nitrogen atoms of the polymer. R is an alkyl, alkenyl, aryl, cycloalkyl or cycloalkenyl group as the hydrophobic group of the hydrophobic compound. If a vinyllog reaction can be applied, the unsaturated vinyl group of the hydrophobic compound is saturated after reacting with the nitrogen atom of the polymer.

According to one embodiment the hydrophobic compound is a saturated compound or an unsaturated compound resulting in a nitrogen containing polymer having saturated hydrophobic side chain substituents.

Hydrophobic compounds may comprise hydrophobic groups containing up to 40, in particular 6-40, even 8-40 carbons.

Hydrophobic chains of hydrophobic compounds may be attached to the nitrogen-containing polymer via an atomic chain which may contain one or more heteroatoms via covalent bonds.

Hydrophobic compounds include (meth) acrylates, alkenyl (meth) acrylates, alkyl (meth) acrylamides, esters, ethers, diazo compounds, carboxylic acids, acid anhydride epoxides, alkyl sulfonates , Alkyl sulfates and mixtures or derivatives thereof. Lauryl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, N-alkyl (meth) acrylamide, N-alkylaminoalkyl (meth) acrylamide, N, N-dialkylaminoalkyl (meth) acrylamide , N-alkylaminoalkyl (meth) acrylate, N, N-dialkylaminoalkyl (meth) acrylate, hexyl chloride, 2-ethylhexyl chloride, octyl chloride, decyl chloride, dodecyl chloride, hexadecyl chloride, octa Decyl chloride, ethyl epoxide, propyl epoxide, (n-, t-, l-) butyl epoxide, pentyl epoxide, hexyl epoxide, 2-ethyl-hexyl epoxide, octyl epoxide, decyl epoxide, dodec Silepoxide, hexadecyl epoxide, octadecyl epoxide, hexene, 2-ethyl-hexene, octene, decene, dodecene, hexadecene, octadecene are exemplified.

The reaction may be carried out in an organic solvent, such as methanol, ethanol, ethylene glycol, which can dissolve the reactant at least partially without being involved in the reaction or under the reaction conditions. Mixtures of such solvents may also be used. In particular, the reaction is carried out in water. The molar ratio (based on amino moles) of the nitrogen containing polymer to the hydrophobic compound is at least 1: 1, in particular 2: 1-99: 1, even more 3: 1-40: 1. The reaction temperature is 25-150 ° C., in particular 60-90 ° C.

In the second step, the hydrophobic nitrogen-containing polymer is reacted with a crosslinking agent. A crosslinking agent refers to a compound capable of crosslinking a resin or forming a bond in cellulose fibers. Crosslinking agents called intralinkers in EP 802 215 A1 include epihalohydrin (eg epichlorohydrin), diepoxides, diacrylates, diacrylamides, dimethacrylamides, mixtures or derivatives thereof. Epichlorohydrin is preferred as crosslinking agent.

The reaction is carried out in an aqueous solution or using a solvent other than water such as ethanol, propanol. The solvent is preferably not reacted with the reactants under the reaction conditions used. In particular, the reaction is carried out in water. The reaction temperature is 0-150 ° C., in particular 4-80 ° C. The molar ratio (based on amino moles) of the hydrophobized nitrogen-containing polymer to the crosslinking agent in the reactant composition is 10: 1-1: 10, in particular 2: 1-1: 2.

In the third step, the method comprises the step of emulsion polymerizing one or more ethylenically unsaturated monomers in the presence of the wet-strength resin formed after the second step. The monomers are styrene, butadiene, vinyl acetate, vinyl amide, alkyl (meth) acrylamide, alkyl (meth) acrylates (e.g. methyl (meth) acrylate, butyl (meth) acrylate, butyl glycidyl (meth) acrylic) Latex, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, (meth) acrylonitrile, isoprene, 1,6-hexanediol diacrylate, or mixtures thereof The wet-strength resin formed as a result of the polymerization process is attached to the formed polymer particles to form a wet-strength enhancer A conventional initiator is used as the polymerization initiator, for example Wako VA 044 is used. A water-soluble initiator is preferred The wet strength resin in the emulsion polymerization acts as an emulsifier during particle formation The formed particles are polymerizable ethylenically unsaturated monomers as exemplified above. The reaction is carried out in water, an organic solvent (eg ethanol, propanol), an organic solvent mixture, or a mixture of water and an organic solvent The reaction temperature is 4-150 ° C., in particular 30-90 ° C. The weight ratio of the resin to 100: 1-1: 100, in particular 10: 1-1: 50.

The present invention also relates to a method of producing a wet-strength resin comprising the first and second steps mentioned above.

The invention also relates to wet-strength enhancers comprising polymer particles and wet-strength resins comprising derivatives of cationic nitrogen-containing polymers with cross-linking agents and saturated hydrophobic side chain substituents.

The polymer particles are formed by polymerizing monomers as above. In particular, the monomer is selected from styrene, acrylates, mixtures or derivatives thereof.

Cationic nitrogen-containing polymers have derivatives of crosslinkers attached to the nitrogen atoms of the polymer and saturated hydrophobic side chain substituents.

Examples of nitrogen containing polymers include commercially available products made according to known methods. Particular examples are polyaminoamides, alkyl polyamines, polyimines and polyvinylamines.

Saturated hydrophobic side chain substituents are attached to the nitrogen atom of the nitrogen containing polymer. Saturated hydrophobic side chain substituents include hydrophobic groups containing hydrophobic straight or branched chain hydrocarbon chains which can be linked via covalent bonds to nitrogen atoms of the nitrogen containing polymer via heteroatoms. Hydrophobic groups include cyclic chains including cyclic hydrocarbons. Combinations of straight chain, branched chain and cyclic hydrocarbons are also included in the concept of hydrophobic groups.

Hydrophobic groups of the hydrophobic side chain contain up to 40, in particular 6-40, even 8-40 carbon atoms.

Hydrophobic side chain substituents are selected from alkyl (meth) acrylates, alkyl (meth) acrylamides, esters, ethers, diazo compounds, carboxylic acids, acid anhydrides, epoxides, alkyl sulfonates, alkyl sulfates, and mixtures or derivatives thereof. do.

Lauryl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, N-alkyl (meth) acrylamide, N-alkylaminoalkyl (meth) acrylamide, N, N-dialkylaminoalkyl (meth) acrylamide , N-alkylaminoalkyl (meth) acrylate, N, N-dialkylaminoalkyl (meth) acrylate, hexyl chloride, 2-ethylhexyl chloride, octyl chloride, decyl chloride, dodecyl chloride, hexadecyl chloride, octa Decyl chloride, ethyl epoxide, propyl epoxide, (n-, t-, l-) butyl epoxide, pentyl epoxide, hexyl epoxide, 2-ethyl-hexyl epoxide, octyl epoxide, decyl epoxide, dodec Silepoxide, hexadecyl epoxide, octadecyl epoxide, hexene, 2-ethyl-hexene, octene, decene, dodecene, hexadecene, octadecene are exemplified.

Other suitable substituents may be derived from substituted succinic anhydrides containing groups selected from alkyl, alkenyl, aralkenyl, aralkyl, ketene dimers or multimers. Further examples are derived from the WO98 / 39376 compound.

The crosslinking agent can be attached to the nitrogen containing polymer to create bonds to the nitrogen containing polymer or cellulose fibers. Crosslinking agents include epihalohydrin (e.g. epichlorohydrin), diepoxide, diacrylate, dimethacrylate, diacrylamide, dimethacrylamide, mixtures or derivatives thereof. Epichlorohydrin is preferred as crosslinking agent.

According to one embodiment the cationic nitrogen-containing polymer is a polyaminoamide-epichlorohydrin resin or a polyamine-epichlorohydrin resin with saturated hydrophobic side chains. At least 10%, in particular at most 100%, of the nitrogen atoms of the cationic resin comprise cationic groups. Up to 100% of the nitrogen atoms of the resin contain up to 50%, in particular 5-30%, of hydrophobic groups. Wet-strength enhancers include compositions of wet-strength resins and polymer particles dissolved in solvents, and in particular, wet-strength enhancers include aqueous compositions. The aqueous composition has a solids content of 5-50% by weight.

The present invention relates to the wet-strength resins disclosed above.

The present invention relates to the use of paper, in particular paper wet-strength resins and wet-strength enhancers, which are published for tissue production. At this time, a resin or a reinforcing agent is added to the aqueous suspension containing cellulose fibers. The amount of resin added to the dry cellulose fibers is 1-70 per tonne of dry cellulose fibers, in particular 5-50, even 15-50 and even 25-50 kg. The mass of the paper produced is less than 70 g / m 2, in particular less than 60 g / m 2, and even less than 40 g / m 2. Paper wet-strength resins and wet-strength enhancers are prepared as aqueous dispersions comprising resin, water, emulsified particles. This dispersion is added to the aqueous cellulose suspension to treat the paper-forming cellulose fibers. Paper wet-strength resins and wet-strength enhancers are added to the produced paper to treat the paper surface. In addition, wetting the paper in combination with known reagents used in paper manufacture, such as sizing agents, softeners, retention agents, dehydrating agents, dry strength enhancers, charge control agents, or other materials such as guar gum, carboxymethyl cellulose, polyacrylamide, polystyrene Strength resins and wet strength agents can be added. Also clay, calcium carbonate, titanium dioxide, talc, aluminum silicate, calcium sulfate, calcium silicate, and traditional fillers disclosed in WO97 / 37080 can be added. And a wet-strength enhancer may be added to the cellulose fiber containing suspension in any ratio. Means such as ion exchange, electrodialysis, enzymatic treatment, filtration and steam treatment to prevent the addition of toxic substances (eg chloropropanediol) to the cellulose suspension before the wet-strength resin and the wet-strength enhancer are added to the aqueous cellulose suspension. Thereby eliminating toxic by-products of the aqueous dispersion containing the wet-strength resin and the wet-strength enhancer. This method is disclosed in EP666 242 A1, EP510 987 A1, WO 92/22601.

The present invention also relates to a process for making paper, in particular tissue, comprising the step of adding a wet-strength resin and a wet-strength enhancer to the aqueous cellulose suspension. The invention also relates to paper, in particular tissue, comprising a wet-strength resin and a wet-strength enhancer. Tissues are articles such as facial, hand, and cosmetic tissues used for personal hygiene, including a substrate formed from a flat material called tissue paper, two key elements, and a softener contained in the substrate. Tissue paper is used for home and industrial purposes and wipes objects by means such as kitchen rolls. Tissue paper is generally made from an aqueous suspension of cellulose fiber with the addition of a wet-strength enhancer. The cellulose fiber-containing aqueous suspension is then dewatered to 7-25% water concentration by means of vacuum dehydration and compression by opposing machine members (eg cylindrical rolls) to obtain a wet cellulose fiber-containing web. The dewatered web is further compressed during delivery and dried by a steam drum known as a Yankee dryer. Vacuum is applied to the web and the multiple Yankee dryer drums to form additional tissue paper structures between the drums. The substrate may consist of a single tissue paper or of two or more tissue paper laminates. In either case, since the substrate is formed from tissue paper, it will be relatively thin in terms of dimensions in the main plane. As a relatively thin planar material, the substrate has two major surfaces. Four important physical properties of tissue paper are strength, softness, water absorption, especially lint resistance when wet (WO95 / 01478). Tissue paper manufacturing methods are disclosed in WO95 / 01478. Another use of tissue paper is to wipe the human body to remove material and to accept emissions. Wet-strength resins and wet-strength enhancers of the invention have 6-40, in particular 8-40, carbon atom-containing hydrophobic side chains. Hydrophobic side chains are selected from alkyl (meth) acrylates, alkyl (meth) acrylamides, esters, ethers, diazo compounds, carboxylic acids, acid anhydrides, epoxides, alkyl sulfonates, alkyl sulfates and mixtures or derivatives thereof. . Other suitable hydrophobic side chains can be derived from substituted succinic anhydrides containing groups selected from alkyl, alkenyl, aralkenyl, aralkyl, ketene dimers or multimers. Further examples are derived from the WO98 / 39376, US9,922,243 compounds. The mass of the paper produced is less than 70 g / m 2, in particular less than 60 g / m 2, and even less than 40 g / m 2. The amount of resin added to the dry cellulose fibers is 1-70 per tonne of dry cellulose fibers, in particular 5-50, even 15-50 and even 25-50 kg. According to one embodiment, the paper wet-strength resin and the wet-strength enhancer of the present invention are added to the aqueous cellulose suspension in an amount of 5-50 kg per tonne of dry cellulose fiber, although synthetic dry strength such as cationic or amphoteric polyacrylamide Additional dry strength enhancers such as reinforcing agents or carboxymethyl cellulose (CMC), starch, guar gum are added in combination with the paper wet-strength resins and wet-strength enhancers of the invention. To control the dry strength of the tissue paper produced, one skilled in the art can select the appropriate hydrophobic wet-strength resin or reinforcing agent to obtain the required tissue paper. Can be adjusted by addition. Thus, tissue paper having high wet strength can be easily produced.

Example 1

Reaction of polyaminoamide (PAIM) with hydrophobic compound (vinyllog addition reaction): 240 g (0.60 amino-mol equivalent) PAIM (53% in water) and 27.3 g (0.15 mole) 2-ethylhexyl acrylate (2-EHAc ) Is heated at 80 ° C. for 6 hours 30 minutes. 176 g of water are then added and the solution is cooled to room temperature. The acrylate conversion is 99.7%.

307 g of PAIM solution hydrophobized above is reacted with 30 ml of epichlorohydrin at 6 ° C. for 6 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 155 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 120 mPa. 11 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Emulsion polymerization: The ratio of resin to styrene is 1: 2.

Nitrogen is injected into a solution of 47 g of wet strength resin prepared above, 104 g of water, and 1.5 ml of antifoaming agent (10% in water). The temperature is increased to 50 ° C. and 0.5 g Wako VA 044 and 1 ml styrene are added to the solution. After 10 minutes additional styrene (25 g total) is added. After 5 hours at 50 ° C. the temperature is raised to 70 ° C. and held at this temperature for 1 hour.

Example 2

Reaction of polyaminoamide (PAIM) with 2-ethylhexyl acrylate (vinyllog addition reaction): 82 g (0.20 amino-mol equivalent) PAIM (52% in water), 1.84 g (0.01 mol) 2-ethylhexyl acrylate (2-EHAc) and 43 g of water are heated at 80 ° C. for 2 hours. The acrylate conversion is 98.9%.

To 125 g of PAIM solution hydrophobized above, 15.4 ml of epichlorohydrin (ECH) was added at 6 ° C. for 6 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 65 ° C. and a viscosity of 120 mPa is reached and 86 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 120 mPa. 11 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Emulsion polymerization: The ratio of resin to styrene is 1: 0.5.

Nitrogen is injected into a solution of 88.5 g of wet strength resin prepared above, 92 g of water, and 1.5 ml of antifoaming agent (10% in water). The temperature is increased to 45 ° C. and 0.04 g Wako VA 044 and 2 ml styrene are added to the solution and the temperature is increased to 50 ° C. After 10 minutes additional styrene (12 g total) is added. After 3 hours at 50 ° C., the reaction mixture is cooled to room temperature.

Example 3

260 g (0.65 amino-molar equivalent) PAIM (53% in water) and 25% 41.0 g (0.16 mole) dodecyl acrylate were heated at 80 ° C. for 4 hours 30 minutes (vinyllog addition reaction). 211 g of water are then added and the solution is cooled to room temperature.

302 g of PAIM solution hydrophobized above is reacted with 30 ml (0.20 mol) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 185 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 120 mPa. 10 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Emulsion polymerization: The ratio of resin / styrene is 1: 1.

Nitrogen is injected into a solution of 75.0 g of wet strength resin prepared above, 100 ml of water, and 1 ml of antifoam (10% in water). The temperature is increased to 50 ° C. and 30 mg Wako VA 044 and 1 ml styrene are added to the solution. After 10 minutes additional styrene (20.5 g total) is added. After 5 hours at 50 ° C. the temperature is increased to 70 ° C. and maintained for one hour.

Example 4

Butyl acrylate is used instead of styrene in emulsion polymerization. Nitrogen is injected into a solution of 75.0 g of wet strength resin (13% solids) and 1.5 g of an antifoaming agent (10% in water) of Example 3. The temperature is increased to 45 ° C. and 0.03 g Wako VA 044 and 2 ml butyl acrylate are added to the solution and the temperature is increased to 50 ° C. After 10 minutes styrene (14.2 ml total) is added. After 2 hours and 50 minutes at 50 ° C., the temperature is increased to 70 ° C. and maintained for one hour.

Example 5

25% 2-ethylhexyl acrylate was used to hydrophobize the PAIM. Emulsification polymerization: Nitrogen is injected into a solution of 121 g of wet strength resin (28% solids), 131 g water and 1 ml antifoaming agent (10% in water) of Example 1. The temperature is increased to 45 ° C. and 0.04 g Wako VA 044 and 2 ml of monomer mixture (styrene: 1,6-hexanediol diacrylate = 0.375: .125) are added to the solution and the temperature is increased to 50 ° C. After 10 minutes the monomer mixture (17 g total) is added. After 3 hours at 50 ° C. it is cooled to room temperature.

Example 6

25% 2-ethylhexyl acrylate was used to hydrophobize the PAIM. A monomer mixture of styrene and t-butyl acrylate (0.45: 0.05) was used. Emulsification polymerization: A solution of 121 g of wet strength resin (28% solids), 131 g of water and 1 ml antifoam (10% in water) of Example 1 Nitrogen is injected. The temperature is increased to 45 ° C. and 0.04 g Wako VA 044 and 2 ml of monomer mixture (styrene: t-butyl acrylate = 0.45: 0.05) are added to the solution and the temperature is increased to 50 ° C. After 10 minutes the monomer mixture (17.0 g total) is added. After 3 hours at 50 ° C. it is cooled to room temperature.

Example 7

630 g (1.67 amino-mol equivalent) PAIM (56% in water) and 12% (0.2 mol) dodecyl acrylate were heated at 80 ° C. for 6 hours (vinyllog addition). 326 g of water are then added and the solution is cooled to room temperature. The acrylate conversion is at least 99%.

1005 g of PAIM hydrophobized above is reacted with 155 g (1.68 moles) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 287 ml of water are added and the temperature is adjusted to 65 ° C. to bring the viscosity to 100 mPa. 50 ml of sulfuric acid (50%) and 513 ml of water are added to adjust the pH to 3.5 and the reaction is terminated.

Example 8

309.5 g (0.81 amino-molar equivalent) PAIM (55% in water) and 15% (0.12 mole) benzyl chloride were heated at 60 ° C. for 6 hours (alkylation reaction). The mixture is then cooled to room temperature.

125.5 g of PAIM hydrophobized above is reacted with 17.7 g (0.19 mol) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 33 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 100 mPa. 6 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Example 9

350 g (0.91 amino-molar equivalent) PAIM (55% in water) and 15% (0.14 mole) 2-ethylhexyl glycidyl ether are heated at 60 ° C. for 7.5 hours (alkylation reaction). The mixture is then cooled to room temperature.

130.4 g of PAIM hydrophobized above is reacted with 17.7 g (0.19 mol) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 33 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 100 mPa. 5.7 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Example 10

274 g (0.71 amino-molar equivalent) PAIM (55% in water) and 3.8% (0.027 mole) alkyl ketene dimer (C18-chain) are heated at 60 ° C. for 6 hours (alkylation reaction). The mixture is then cooled to room temperature.

127.2 g of PAIM hydrophobized above is reacted with 17.7 g (0.19 mol) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 33 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 100 mPa. 5.7 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Example 11

274 g (0.71 amino-molar equivalent) PAIM (55% in water) and 5% (0.036 mole) alkenyl succinic anhydride (C18-chain) are heated at 60 ° C. for 6 hours (alkylation reaction). The mixture is then cooled to room temperature.

124.3 g of PAIM hydrophobized above is reacted with 17.7 g (0.19 mol) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 33 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 100 mPa. 5.7 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Example 12

185.4 g (0.48 amino-mol equivalent) PAIM (54% in water) and 10% (0.048 mol) hexanediol diacrylate (90%) are heated at 80 ° C. for 4.5 hours (alkylation reaction). The mixture is then cooled to room temperature. The acrylate conversion is at least 99%.

124.0 g of PAIM hydrophobized above is reacted with 17.7 g (0.19 mol) of epichlorohydrin (ECH) at 6 ° C. for 4 minutes. The temperature is then raised to 20 ° C. The temperature is then increased to 50 ° C. and a viscosity of 120 mPa is reached and 33 ml of water are added and the temperature is adjusted to 65 ° C. so that the viscosity is 100 mPa. 5.7 ml of sulfuric acid (50%) is added to adjust the pH to 3.5 and the reaction is terminated.

Applied test

Paper sheets are produced on a dynamic sheet former "Formette". The furnish consists of 65% TCF and 35% CTMP refined to 25 ° SR. The paper is artificially cured at 105 ° C for 10 minutes before paper conditioning according to DIN5312. Tensile tests are performed as published in DIN53112. The paper is immersed for 60 minutes at room temperature for the wet tensile test. For comparison, data are presented for paper made using conventional polyaminoamide epichlorohydrin resins. The paper sheets presented in Tables 1-4 were tested three times with varying amounts of wet-strength enhancer added. In Example 1-6, 20 kg of a wet strength modifier was added per ton of cellulose fiber and the mass was 55 g / m 2. In Example 7-12, 15,20, and 30 kg of wet strength enhancer per tonne of cellulose fiber were added and the mass was 30 g / m 2. As a result, the observed relative intensities varied. Reference resin (conventional resin) was also measured. Wet-strength resins and reinforcers show superior effects over conventional resins used as reference at the same addition level.

Sample Dry tensile index (Nm / g) Wet Tensile Index (Nm / g) Relative Wet Strength (%) Conventional resin 49 13 27 Example 1 Wet Strength Emulsion 37 14 37 Example 2 Wet Strength Emulsion 51 15 30 Example 3 Wet Strength Emulsion 37 12 32 Example 3 Wet Strength Emulsion 37 13 34 Example 4 Wet Strength Emulsion 33 12 36 Example 5 Wet Strength Emulsion 35 11 31 Example 6 Wet Strength Emulsion 37 12 33

15kg sample per ton of paper Dry tensile index (Nm / g) Wet Tensile Index (Nm / g) Relative Wet Strength (%) Conventional resin 40.3 9.7 23.9 Example 7 Wet Strength Emulsion 31.6 9.3 29.5 Example 8 Wet Strength Emulsion 38.3 11.0 28.7 Example 9 Wet Strength Emulsion 33.6 9.0 26.7 Example 10 Wet Strength Emulsion 40.3 10.7 26.6 Example 11 Wet Strength Emulsion 35.3 10.7 30.2 Example 12 Wet Strength Emulsion 38.6 10.3 26.7

20kg sample per ton of paper Dry tensile index (Nm / g) Wet Tensile Index (Nm / g) Relative Wet Strength (%) Conventional resin 41.6 10.3 24.8 Example 7 Wet Strength Emulsion 31.6 9.3 29.5 Example 8 Wet Strength Emulsion 38.0 10.8 28.5 Example 9 Wet Strength Emulsion 35.3 10.0 28.6 Example 10 Wet Strength Emulsion 39.3 11.0 28.0 Example 11 Wet Strength Emulsion 35.0 11 31.4 Example 12 Wet Strength Emulsion 37.3 10.7 28.6

30kg sample per ton of paper Dry tensile index (Nm / g) Wet Tensile Index (Nm / g) Relative Wet Strength (%) Conventional resin 40.0 10.7 26.7 Example 7 Wet Strength Emulsion 31.6 10.0 31.6 Example 8 Wet Strength Emulsion 39.3 11.7 29.7 Example 9 Wet Strength Emulsion 34.0 11.0 32.4 Example 10 Wet Strength Emulsion 38.3 11.3 29.6 Example 11 Wet Strength Emulsion 34.3 11.3 33.0

Claims (28)

Manufacturing method of paper wet-strength enhancer comprising the following steps: Nitrogen-containing polymer selected from polyamine or polyaminoamide Lauryl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, N-alkyl (meth) acrylamide, N-alkylaminoalkyl (meth) acrylamide, N, N-dialkylaminoalkyl (meth) acrylamide , N-alkylaminoalkyl (meth) acrylate, N, N-dialkylaminoalkyl (meth) acrylate, hexyl chloride, 2-ethylhexyl chloride, octyl chloride, decyl chloride, dodecyl chloride, hexadecyl chloride, octa Decyl chloride, ethyl epoxide, propyl epoxide, (n-, t-, l-) butyl epoxide, pentyl epoxide, hexyl epoxide, 2-ethyl-hexyl epoxide, octyl epoxide, decyl epoxide, dodec 6-40 carbon atoms selected from the group consisting of sil epoxide, hexadecyl epoxide, octadecyl epoxide, hexene, 2-ethyl-hexene, octene, decene, dodecene, hexadecene, octadecene and mixtures thereof By reacting with a hydrophobic compound containing a hydrophobic chain Forming a saturated hydrophobic side chain substituent comprising a hydrophobic chain having 6-40 carbon atoms on the polymer; The obtained hydrophobized nitrogen-containing polymer is reacted with a crosslinking agent selected from the group consisting of epihalohydrin, diepoxide, diacrylate, dimethacrylate, diacrylamide, dimethacrylamide and mixtures to contain cationic nitrogen A second step of forming a resin; And One selected from the group consisting of styrene, butadiene, vinyl acetate, vinyl amide, alkyl (meth) acrylamide, alkyl (meth) acrylate, (meth) acrylonitrile, or mixtures thereof in the presence of the formed wet-strength resin The third step of emulsion polymerizing the above ethylenically unsaturated monomer. delete The method of claim 1, wherein the first step is a vinyllog addition reaction or an alkylation reaction. delete The method of claim 1 wherein the hydrophobic compound comprises 8-40 carbon atom-containing hydrophobic chains. The method of claim 1 wherein the hydrophobic compound comprises at least one hetero atom containing atom chain. The method of claim 1 wherein the crosslinker is epichlorohydrin. delete The method of claim 1 wherein the hydrophobic compound is a saturated compound or an unsaturated compound and produces a nitrogen-containing polymer having saturated side chain substituents. delete Paper moisture-strength enhancer comprising: Lauryl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, N-alkyl (meth) acrylamide, N-alkylaminoalkyl (meth) acrylamide, N, N-dialkylaminoalkyl (meth) acrylamide , N-alkylaminoalkyl (meth) acrylate, N, N-dialkylaminoalkyl (meth) acrylate, hexyl chloride, 2-ethylhexyl chloride, octyl chloride, decyl chloride, dodecyl chloride, hexadecyl chloride, octa Decyl chloride, ethyl epoxide, propyl epoxide, (n-, t-, l-) butyl epoxide, pentyl epoxide, hexyl epoxide, 2-ethyl-hexyl epoxide, octyl epoxide, decyl epoxide, dodec 6-40 carbon atoms selected from the group consisting of sil epoxide, hexadecyl epoxide, octadecyl epoxide, hexene, 2-ethyl-hexene, octene, decene, dodecene, hexadecene, octadecene and mixtures thereof Cationic nitrogen-containing polymers having saturated hydrophobic side chain substituents, including having a hydrophobic chain having a polyamine or a polyaminoamide, Wet strength resins including derivatives of cross-linking agents selected from the group consisting of epihalohydrin, diepoxide, diacrylate, dimethacrylate, diacrylamide, dimethacrylamide and mixtures; And One or more ethylenically unsaturated monomers selected from the group consisting of styrene, butadiene, vinyl acetate, vinyl amide, alkyl (meth) acrylamide, alkyl (meth) acrylate, (meth) acrylonitrile, or mixtures thereof are polymerized. Polymer particles 12. The paper wet-strength enhancer of claim 11 wherein the saturated hydrophobic side chain substituent comprises a hydrophobic group attached to the nitrogen atom of the nitrogen containing polymer via an atomic chain containing 6-40 carbon atoms. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete