MX2007007658A - Composition for improving the retention and drainage in the manufacture of paper - Google Patents

Abstract

A method of improving retention and drainage in a papermaking process is disclosed. The method provides for the addition of an associative polymer, a polyelectrolyte and optionally a siliceous material to the papermaking slurry. Additionally, a composition comprising an associative polymer, and a polyelectrolyte and optionally further comprising cellulose fiber is disclosed.

Description

IMPROVED RETENTION AND SLOPE IN PAPER MANUFACTURE CROSS REFERENCE TO RELATED REQUESTS This application claims the benefit of US Provisional Application No. 60 / 640,180, filed on December 29, 2004, and US Provisional Application No. 60 / 694,058, filed on June 24, 2005, the contents complete of each are incorporated herein for reference.

FIELD OF THE INVENTION This invention relates to the process for making paper and cardboard of a cellulosic material, using a flocculation system.

BACKGROUND Retention and drainage is an important aspect of papermaking. It is known that certain materials can provide improved retention and / or dewatering properties in the production of paper and cardboard. The manufacture of cellulose fiber sheets, particularly paper and cardboard, includes the following: 1) producing an aqueous slurry of cellulosic fiber which may also contain extenders or pigments of inorganic material; 2) deposit this slurry on an endless belt or fabric for mobile paper production; and 3) forming a sheet of the solid components of the slurry upon dewatering the water. The above is followed by pressing and drying the sheet to remove water as well. Organic and inorganic chemicals are often added to the slurry prior to the sheeting step to make the papermaking method less expensive, faster, and / or to achieve specific properties in the final paper product. The paper industry continually strives to improve paper quality, increase productivity and reduce manufacturing costs. Chemicals are often added to the fibrous slurry before reaching the endless belt or papermaking cloth to improve the drainage / drainage and retention of solids; These chemicals are called retention aids and / or dewatering. The draining or draining of the fibrous slurry in the endless belt or papermaking cloth is often the limiting step to achieve faster variations of papermaking machine. Improved drainage can also result in a drier sheet in the press and sections of the dryer, resulting in reduced energy consumption. In addition, as this is the stage in the papermaking method that determines many of the final properties of the sheet, the retention aid and / or dewatering can impact yield attributes of the final paper sheet. With respect to solids, papermaking retention aids are used to increase the retention of fine raw material solids in the web during the turbulent dewatering and continuous paper forming method. Without adequate retention of fine solids, these are lost in the mill affluent or accumulate at high levels in the recirculation of white water circuit, potentially causing deposits to accumulate. Additionally, insufficient retention increases the cost of the paper manufacturer due to the loss of additives intended to be absorbed into the fiber. The additives may provide opacity, strength, sizing or other desirable properties to the paper. Water soluble polymers of high molecular weight (M) with cationic or anionic charge have traditionally been used as retention and dewatering aids. The recent development of inorganic microparticles, when used as a retention and dewatering aid, in combination with water-soluble polymers of high MW, have demonstrated superior retention and dewatering efficiency compared to conventional high MW water-soluble polymers. U.S. Patent Nos. 4,294,885 and 4,388,150 teach the use of starch polymers with colloidal silica. The U.S. Patent Nos. 4,643,801 and 4,750,974 teach the use of coacervated binder of cationic starch, colloidal silica and anionic polymer. U.S. Patent No. 4,753,710 teaches flocculation of the pulp feedstock with a high M cationic flocculant, inducing shear stress to the flocculated raw material, and then introducing bentonite clay to the raw material. The effectiveness of the polymers or copolymers used will vary depending on the type of monomers from which it is composed, the arrangement of the monomers in the polymer matrix, the molecular weight of the synthesized molecule and the method of preparation. It has recently been found that when water-soluble copolymers are prepared under certain conditions they exhibit unique physical characteristics. These polymers are prepared without chemical crosslinking agents. Additionally, the copolymers provide unforeseen activity in certain applications including papermaking applications such as retention aids and dewatering. Anionic copolymers which exhibit unique characteristics are described in WO 03/050152 Al, the entire contents of which is incorporated herein by reference. The cationic and amphoteric copolymers which exhibit the unique characteristics were described in the U.S. serial number 10 / 728,145, the full content of which is incorporated herein by reference. The use of inorganic particles with linear acrylamide copolymers is known in the art. Recent patents teach the use of these inorganic particles with water-soluble anionic polymers (US 6,454,902) or specific cross-linked materials (US 6,454,902, US 6,524,439 and US 6,616,806). However, there is a need to improve dewatering and retention performance.

COMPENDIUM OF THE INVENTION A method for improving retention and dewatering in a process for making paper is described. The method allows the addition of an associative polymer and a synthetic polyelectrolyte to a slurry to make paper. A method for improving retention and dewatering in a process for making paper is described. The method allows the addition of an associative polymer and a cyclic organic material to a slurry to make paper. Additionally, a composition comprising an associative polymer, a synthetic polyelectrolyte and optionally, further comprises cellulose fiber is disclosed. Additionally, a composition comprising an associative polymer, a polyelectrolyte is described synthetic, a siliceous material and optionally, further comprises cellulose fiber.

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a synergistic combination comprising a water-soluble copolymer prepared under certain conditions (hereinafter referred to as "associative polymer") and at least one synthetic polyelectrolyte. It has surprisingly been found that this synergistic combination results in retention performance and dewatering superior to that of the individual components. Synergistic effects occur when the combination of components are used together. It has been unexpectedly found that the use of a synthetic polyelectrolyte in combination with associative polymers, such as the copolymers described in WO 03/050152 Al or US 2004/0143039 Al, results in improved retention and dewatering. The present invention also provides a composition comprising an associative polymer and at least one synthetic polyelectrolyte. The present invention also provides a composition comprising an associative polymer, a synthetic polyelectrolyte and a siliceous material. The present invention also provides a composition comprising an associative polymer and a synthetic polyelectrolyte and a cellulose fiber. The present invention also provides a composition comprising an associative polymer, a synthetic polyelectrolyte, a siliceous material and cellulose fiber. The use of multi-component systems in the manufacture of paper and cardboard provides the opportunity to improve performance by using materials that have different effects on the process and / or product. In addition, the combinations can provide properties impossible to obtain with the components individually. Synergistic effects occur in the multicomponent systems of the present invention. It is also noted that the use of the associative polymer as a retention and dewatering aid has an impact on the performance of other additives in the paper making system. Improved retention and / or dewatering can have both direct and indirect impact. A direct impact refers to the retention aid and dewatering that acts to retain the additive. An indirect impact refers to the effectiveness of the retention aid and dewatering to retain fillers and fines on which the additive is bound either by physical or chemical means. In this way, by increasing the amount of filler or fines retained in the sheet, the amount of additive retained increases in a concomitant manner. The term "filler" refers to particulate materials, normally inorganic in nature, that are added to the cellulosic pulp slurry to provide certain attributes or are a lower cost substitute for a portion of the cellulose fiber. Its relatively small size, in the order of 0.2 to 10 microns, the lower aspect ratio and the chemical nature that results is not adsorbed on the large fibers even very small to be trapped in the fibrous web that is the paper sheet. The term "fines" refers to fibers or small fibrils, usually less than 0.2 mm long and / or capable of passing through a 200 mesh screen. Since the level of use of the retention aid and dewatering increases the amount of additive retained in the sheet. This can provide either an improvement to the property, providing a sheet with an increased performance attribute, or allows the paper manufacturer to reduce the amount of additive added to the system, reducing the cost of the product. In addition, the amount of these materials in the recirculating water, or white water, used in the papermaking system is reduced. This reduced level of material, which under some conditions can be considered to be an undesirable contaminant, can provide a more efficient papermaking process or reduce the need for sweepers or other aggregate materials to control the level of undesirable material. The term additive, as used herein, refers to materials added to the paper slurry to provide paper-specific attributes and / or improve the efficiency of the papermaking process. These materials include, but are not limited to sizing agents, wet strength resins, dry strength resins, starch and starch derivatives, dyes, contaminant control agents and biocides. The associative polymer useful in the present invention can be described as follows: A water-soluble polymer composition comprising the formula: t-B-co-F-f (l) wherein B is a non-ionic polymer segment formed from the polymerization of one or more non-ionic ethylenically unsaturated monomers; F is one or more polymeric anionic, cationic or a combination of anionic and cationic segments, formed by polymerization of one or more anionic and / or ethylenically unsaturated cationic monomers; the ratio in molar% of B: F is from 95: 5 to 5:95; and the water-soluble copolymer is prepared through a water-in-oil emulsion polymerization technique that employs at least one emulsifying surfactant consisting of at least one diblock or triblock polymeric surfactant wherein the ratio of at least one diblock or triblock to monomer surfactant is at least about 3: 100 and wherein; the water-in-oil emulsion polymerization technique comprises the steps of: (a) preparing an aqueous solution of monomers, (b) contacting the aqueous solution with a surfactant containing hydrocarbon liquid or a mixture of surfactant to form a Reverse emulsion, (c) cause the monomer in the emulsion to polymerize by free radical polymerization in a pH range from about 2 to less than 7. The associative polymer can be an anionic copolymer. The anionic copolymer is characterized in that the Huggins constant (k ') determined between 0.0025% by weight to 0.025% by weight of the 0.01M NaCl copolymer is greater than 0.75; and the storage module (C) for active of 1.5% by weight of copolymer solution in 4.6 Hz greater than 175 Pa. The associative polymer can be a cationic copolymer. The cationic copolymer is characterized in that the Huggins constant (k ') determined between 0.0025% by weight to 0.025% by weight of the 0.01M NaCl copolymer is greater than 0.5; and has a storage module (G ') for assets of 1.5% by weight of copolymer solution at 6.3 Hz greater than 50 Pa. The associative polymer can be an amphoteric copolymer. The amphoteric copolymer is characterized in that its Huggins constant (k ') determined between 0.0025 wt% to 0.025 wt% of the 0.01 M NaCl copolymer is greater than 0.5; and the copolymer has a storage modulus (G ') for active of 1.5% by weight of copolymer solution at 6.3 Hz greater than 50 Pa. Reverse emulsion polymerization is a standard chemical process for preparing high molecular weight water soluble polymers or copolymers. In general, a reverse emulsion polymerization process is conducted by 1) preparing an aqueous solution of the monomers, 2) contacting the aqueous solution with a hydrocarbon liquid containing the appropriate emulsifying surfactant (s) or a mixture of the agent surfactant forming a reverse monomer emulsion, 3) subjecting the monomer emulsion to free radical polymerization, and optionally, 4) adding a switch surfactant to improve the inversion of the emulsion when added to water. Reverse emulsion polymers are usually water soluble polymers based on ionic or nonionic monomers. Polymers containing two or more monomers, also referred to as copolymers, can be prepared by the same process. These comonomers can be anionic, cationic, zwitterionic, nonionic or a combination thereof. Typical nonionic monomers include, but are not limited to acrylamide; methacrylamide; N-alkyl acrylamides, such as N-methylacrylamide; N, -dialkylacrylamides, such as N, N-dimethylacrylamide; methyl acrylate; methyl methacrylate; acrylonitrile; N-vinyl methylacetamide; N-vinyl formamide; N-vinyl methylformamide; vinyl acetate; N-vinyl pyrrolidone; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate or hydroxypropyl (meth) acrylate; mixtures of any of the foregoing and the like. Nonionic monomers of a more hydrophobic nature can also be used in the preparation of the associative polymer. The term "more hydrophobic" is used herein to indicate that these monomers have reduced solubility in aqueous solutions; this reduction can be essentially zero, meaning that the monomer is not soluble in water. It is noted that the monomers of interest are also referred to as polymerizable surfactants or surfers. These monomers include, but are not limited to, alkyl acrylamides; ethylenically unsaturated monomers having pendant aromatic and alkyl groups, and ethers of the formula CH2 = CR 'CH2OAmR wherein R' is hydrogen or methyl; A is a polymer of one or more cyclic ethers such as ethylene, propylene oxide and / or butylene oxide; and R is a hydrophobic group; vinyl alkoxylates; allyl alkoxylates; and allyl phenylpolyoletersulfates. Exemplary materials include, but are not limited to, methyl methacrylate, styrene, t-octyl acrylamide, and an allyl phenyl polyolether sulfate marketed by Clariant as Emulsogen® APG 2019. Exemplary anionic monomers include, but are not limited to, acids and salts free of: acrylic acid; methacrylic acid; maleic acid; Itaconic acid; Acid acrylamidoglycolic; 2-acrylamido-2-methyl-1-j propanesulfonic acid; 3-allyloxy-2-hydroxy-1-propanesulfonic acid; styrenesulfonic acid; vinylsulfonic acid; vinyl phosphonic acid; 2-acrylamido-2-methylpropanphosphonic acid; mixtures of any of the foregoing and the like. Exemplary cationic monomers include, but are not limited to, cationic ethylenically unsaturated monomers: such as the base or free salt of dialkyl dialkylammonium halides, such as diallyldimethylammonium chloride; (meth) acrylates of dialkylaminoalkyl compounds, such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (me) acrylate, 2-hydroxydimethylaminopropyl (meth) acrylate, aminoethyl (meth) acrylate, and salts and quaternary groups thereof; N, N-dialkylaminoalkyl (meth) acrylamides, such as N, N- dimethylaminoethylacrylamide, and the salts and quaternary groups thereof; and mixtures of the foregoing and the like. The co-monomers can be present in any proportion. The resulting associative polymer can be nonionic, cationic, anionic or amphoteric (it contains both cationic and anionic charge). The molar ratio of the nonionic monomer to the anionic monomer (B: F or Formula I) can fall within the range of 95: 5 to 5:95, preferably the range is from about 75:25 to about 25:75 and even more preferably the range is from about 65:35 to about 35:65 and more preferably from about 60:40 to about 40:60. In this sense, the molar percentages of B and F must add up to 100%. It will be understood that more than one kind of nonionic monomer can be presented in Formula I. It will also be understood that more than one kind of ionic monomer may be present in Formula I. In a preferred embodiment of the invention the associative polymer, when it is an anionic copolymer, is defined by Formula I wherein B, the non-ionic polymer segment, is the repeating unit formed after the polymerization of acrylamide; and F, the anionic polymer segment, is the repeating unit formed after the polymerization of a salt or free acid or acrylic acid and the The molar percentage ratio of B: F is from about 75:25 to about 25:75. The physical characteristics of the associative polymer, when it is an anionic copolymer, are unique because the Huggin constant (k ') as determined in 0.01 M NaCl is greater than 0.75 and the storage modulus (G') for assets of 1.5 % by weight of polymer solution at 4.6 Hz is greater than 175 Pa, preferably greater than 190 and even more preferably greater than 205. Huggins constant is greater than 0.75, preferably greater than 0.9 and even more preferably greater than 1.0. The molar ratio of nonionic monomer to cationic monomer (B: F of Formula I) can fall within the range of 99: 1 to 50:50, or 95: 5 to 50:50, or 95: 5 to 75:25, or 90:10 to 60:45, preferably the range is from about 85:15 to about 60:40 and even more preferably the range is from about 80:20 to about 50:50. In this sense, the percentages of B and F must add up to 100%. It should be understood that more than one kind of nonionic monomer may be present in Formula I. It should also be understood that more than one class of cationic monomer may be present in Formula I. With respect to the molar percentages of the amphoteric copolymers of Formula I, the minimum amount of each of the anionic, cationic and nonionic monomers it is 1% of the total amount of the monomer used to form the copolymer. The maximum amount of the nonionic, anionic or cationic is 98% of the total amount of the monomer used to form the copolymer. Preferably, the minimum amount of any anionic, cationic and non-ionic monomer is 5%, more preferably the minimum amount of any anionic, cationic and non-ionic monomer is 7% and even more preferably the minimum amount of any anionic, cationic and Nonionic is 10% of the total amount of monomer used to form the copolymer. In this sense, the molar percentages of the anionic, cationic and non-ionic monomer must be added up to 100%. It should be understood that more than one kind of nonionic monomer may be present in Formula I, more than one class of cationic monomer may be present in Formula I, and that more than one kind of anionic monomer may be presented in Formula I. The physical characteristics of the associative polymer, when it is a cationic or amphoteric copolymer, are unique in that the Huggins constant (k ') as determined in 0.01 NaCl is greater than 0.5 and the storage modulus (G') for active of 1.5% by weight of polymer solution at 6.3 Hz is greater than 50 Pa, preferably greater than 10 and even more preferably greater than 25, or greater than 50, or greater than 100, or greater than 175, or greater than 200 The Huggins constant is greater than 0.5, preference greater than 0.6, or greater than 0.75, or greater than 0.9 or greater than 1.0. The emulsifying surfactant or surfactant mixture used in a reverse emulsion polymerization system has a significant effect on both the manufacturing process and the resulting product. The surfactants used in emulsion polymerization systems are known to those skilled in the art. These surfactants typically have a range of HLB (Hydrophilic Lipophilic Balance) values which is dependent on the total composition. One or more emulsifying surfactants may be used. The emulsification surfactant (s) of the polymerization products that are used to produce the associative polymer include at least one diblock or triblock polymeric surfactant. It is known that these surfactants are highly effective emulsion stabilizers. The choice and quantity of the emulsifying surfactant (s) in order to produce a reverse monomeric emulsion for polymerization. Preferably, one or more surfactants is selected in order to obtain a specific HLB value. Polymeric diblock and triblock emulsification surfactants are used to provide unique materials. When diblock and triblock polymeric emulsification surfactants are used in the necessary amount, unique polymers are produced which exhibit unique characteristic, as described in WO 03/050152 Al and US 2004/0143039 Al, the complete contents of each are incorporated in the present for reference. Exemplary diblock and triblock polymeric surfactants include, but are not limited to, diblock and triblock copolymers based on polyester derivatives of fatty acids and poly [ethylene polyoxide] (e.g., Hypermer® B246SF, Uniquema, New Castle, DE) , diblock and triblock copolymers based on polyisobutylene succinic anhydride and poly [ethylene oxide], reaction products of ethylene oxide and propylene oxide with ethylenediamine, mixtures of any of the foregoing and the like. Preferably, the diblock and triblock copolymers are based on polyester derivatives of fatty acids and poly [ethylene oxide]. When a triblock surfactant is used, it is preferable that the triblock contains two hydrophobic regions and a hydrophilic, i.e., hydrophobic-hydrophilic-hydrophobic region. The amount (based on percent by weight) of the diblock or triblock surfactant is dependent on the amount of monomer used to form the associative polymer. The ratio of diblock or triblock surfactant to monomer is at least about 3 to 100. The amount of diblock or triblock to monomer surfactant may be greater than 3 to 100 and preferably at least about 4 to 100 and more preferably 5 to 100 and even more preferably about 6 to 100. The diblock or triblock surfactant It is the primary surfactant of the emulsification system. A secondary emulsification surfactant may be added to facilitate handling and processing, to improve emulsion stability and / or to alter the emulsion viscosity. Examples of secondary emulsification surfactants include, but are not limited to, sorbitan fatty acid esters, such as sorbitan monooleate (eg, Atlas G-946, Uniquema, New Castle, DE), sorbitan fatty acid esters ethoxylates, polyethoxylated sorbitan fatty acid esters, ethylene oxide and / or propylene oxide adducts of alkylphenols, ethylene oxide and / or propylene oxide adducts of long chain fatty acid alcohols, block copolymers of mixed ethylene oxide / propylene oxide, alkanolamides, sulphosuccinates and mixtures thereof and the like. The polymerization of the inverse emulsion can be carried out in any manner known to those skilled in the art. Examples can be found in many references, including for example, Allcock and Lampe, Contemporary Polymer Chemistry, (Englewood Cliffs, New Jersey, PRENTICE-HALL, 1981), chapters 3-5. A representative inverse emulsion polymerization is prepared as follows. To a suitable reaction flask equipped with an overhead mechanical stirrer, thermometer, nitrogen spray tube, and condenser is charged in oil phase of paraffin oil (135.0 g, Exxsol® D80 oil, Exxon-Houston, TX) and surfactants (4.5 g Atlas® G-946 and 9.0 g Hypermer® B246SF). The temperature of the oil phase is then adjusted to 37 ° C. An aqueous phase is prepared separately which comprises 53% by weight of acrylamide solution in water (126.5 g), acrylic acid (68.7 g), deionized water (70.0 g), and chelating solution Versenex® 80 (Dow Chemical) (0.7 g). The aqueous phase is then adjusted to pH 5.4 with the addition of ammonium hydroxide solution in water (33.1 g, 29.4% by weight as NH3). The temperature of the aqueous phase after neutralization is 39 ° C. The aqueous phase is then charged to the oil phase while mixing simultaneously with a homogenizer to obtain a stable water-in-oil emulsion. This emulsion is then mixed with a 4 blade glass stirrer while being sprayed with nitrogen for 60 minutes. During the nitrogen spray, the temperature of the emulsion is adjusted to 50 ± 1 ° C. Then, the spray is discontinued and the implements a nitrogen mattress. The polymerization is started by feeding a solution of 3% by weight of 2,2'-azobisisobutyronitrile (AIBN) in toluene (0.213 g). This corresponds to an initial AIBN load, such as AIBN, of 250 ppm on a total monomer basis. During the course of feeding the batch temperature was brought to exotherm to 62 ° C (~ 50 minutes), after which the batch was maintained at 62 + 1 ° C. The batch feed was then maintained at 62 ± 1 ° C for 1 hour. Then a solution of 3% by weight AIBN in toluene (0.085 g) was loaded in less than one minute. This corresponds to a second load of AIBN of 100 ppm in a total monomeric base. Then, the batch was maintained at 62 + 1 ° C for 2 hours. The batch is then cooled to room temperature, and the surfactant (s) is added. The associative polymer emulsion is usually inverted at the application site resulting in an aqueous solution of 0.1 to 1% active copolymer. This diluted solution of associative polymer is then added to the paper process that affects retention and dewatering. The associative polymer can be added to the coarse pulp or thin pulp, preferably the thin pulp. The associative polymer can be added to a feed point, or it can be fed separately so that the associative polymer is fed at the same time to two or more separate feeding points. Typical pulp addition points include the feed point (s) before the feed pump, after the feed pump and before the pressure screen, or after the pressure screen. The associative polymer can be added in any effective amount to achieve flocculation. The amount of polymer could be more than 0.5 kg per metric ton of cellulose pulp (dry basis). Preferably, the associative polymer is employed in an amount of at least about 0.03 pounds, to about 0.5 kg, of the active copolymer per metric ton of cellulose pulp, based on the pulp dry weight. The concentration of the copolymer is preferably from about 0.05 to about 0.5 kg of the active copolymer per metric ton of dry cellulose pulp. More preferably, the copolymer is added in an amount of about 0.05 to 0.4 kg per metric ton of cellulosic pulp, and more preferably about 0.1 to about 0.3 kg per metric ton based on the dry weight of the cellulosic pulp. The second component of the retention and drainage system may be one of a number of ionic polymeric materials or synthetic polyelectrolytes ("polyelectrolytes"). The material can be a simple product or mixture of materials. These materials may differ in their nature chemistry, as influenced by the monomeric composition, nature of the ionic functionality, amount of ionic functionality, distribution of ionic functionality next to the polymer chain, and the physical nature of the polymer, such as molecular weight, charge density and secondary structure / tertiary This component can be selected from at least one of the various polymer groups including, but not limited to, acrylamide-based polymers, such as anionic polyacrylamides and cationic polyacrylamides; polyaminoamine-epihalohydrin resins; polyamines; polyimines and derivatives of any of the foregoing, and the like. What is meant by derivative is polymers with at least one additional functional group or component. The functional groups may be selected from, but not limited to the group including epoxy, azetidinium, aldehyde, carboxyl group, acrylate and derivatives thereof, acrylamide and derivatives thereof, and quaternary diamine. Examples include, but are not limited to reactive polymers based on acrylamide, polyamidoamine-epihalohydrin resins and polyamines, and polyimines, such as functionalized polyacrylamides (HERCOBOND 1000® manufactured by Hercules Incorporated) such as those described in US Patent No. 5,543,446, which is incorporated in the present in its entirety, curling aids such as CREPETROL® A3025 described in U.S. Patent No. 5,338,807, which is incorporated herein in its entirety, and polyaminoamine -epihalohydrin resins such as those described in U.S. Patent Nos. 2,926,116 and 2,925,154, incorporated for reference In its whole. Polymers can be known in the art under a number of terms, including, but not limited to, coagulant, dry strength resin, flocculant, promoter resin, and wet strength resin. The term synthetic polyelectrolyte is used herein, to mean a polymer comprising one or more monomers, of which at least one monomer is anionic or cationic. Synthetic polyelectrolyte which is derived are contemplated within the scope of this invention and are considered for the purposes of this invention to be within the definition of synthetic polyelectrolytes. Anionic or cationic monomers are most often used to make copolymers with a nonionic monomer such as acrylamide. These polymers can be provided by a variety of synthetic processes including, but not limited to, suspension, dispersion and reverse emulsion polymerization. For the last process, a microemulsion can also be used. Alternatively, the term synthetic polyelectrolyte is used to mean a polymer obtained by polymerization of one or more non-ionic monomers followed by derivatization or reaction with another portion. An example is a polyamidoamine-epihalohydrin polymer formed by the reaction of an amine and a dicarboxylic acid which is the reaction with an epihalohydrin. Exemplary amine includes, but is not limited to, diamine such as ethylenediamine; triamines such as diethyltriamine; and tetramines such as triethylene tetramine. Exemplary dicarboxylic acid includes, but is not limited to, atypical acid. Exemplary epihalohydrins include, but are not limited to epichlorohydrin. The comonomers of the synthetic polyelectrolyte can be present in any proportion. The resulting synthetic polyelectrolyte can be cationic, anionic or amphoteric (it contains both cationic and anionic charge). Ionic water-soluble polymers, or polyelectrolytes, are normally produced by copolymerizing a non-ionic monomer with an ionic monomer, or by post-polymerization of a non-ionic polymer to impart ionic functionality. An example of this post-polymerization hydrolysis of polymers and copolymers of N-vinyl formamide producing poly (vinylamine). Examples of preferred synthetic polyelectrolytes useful herein include but are not limited to cationic copolymers with 20 mole percent or higher cationic monomer content, an anionic copolymer with mole percent or less anionic monomer content, polyamines, poly-diallyldimethylammonium chlorides, polyamidoamine-epichlorohydrin resins, or modified polyethylenimines. An example of cationic copolymers with 20 mole percent or higher cationic monomer content is a copolymer of 2-acryloyloxytrimethylammonium chloride (AETAC) / acrylamide with 20 mole percent or higher AETAC content. In one embodiment of the anionic copolymer with 20 mole percent or less anionic monomer content is an acidic content of acrylic acid / acrylamide copolymer. The terms coagulant and flocculant are best defined in comparative terms since their chemical nature may be similar. One mode of differentiation is that the coagulants are usually lower in molecular weight than the flocculants. A second mode is the mechanism by which they cause aggregation of colloidal particles. A coagulant acts to add particle suspension by destabilizing or changing the ionic nature of the particle. This results in the complete system having a zeta potential closer to zero. Flocculation destabilizes the suspension by joining the particles together through the long chains of the polymer. A coagulant causes an irreversible aggregation, while the effect of a flocculant is reversible. Finally, most of the coagulants are cationic by nature, while the flocculants are cationic or anionic. Examples of coagulants that can be used as polyelectrolytes in the present invention include, but are not limited to, linear and branched polyamine condensation products with epichlorohydrin and amines (dimethylamine, ethylenediamine, etc.), such as PerForm® PC1279, a Hercules product. Incorporated, Wilmington, DE; poly (diallyldimethylammonium chloride) or poly (DADMAC), such as PerForm® 8717, a product of Hercules Incorporated; polyethyleneimine and modified polyethyleneimines such as Polymin® SK, a product of BASF Corporation (Mount Olive, NJ); polyamidoamines, such as Reten® 204LS, a product of Hercules Incoporated; hydrolyzed and quaternized hydrolysates, and chemical derivatives of polymers and copolymers of N-vinyl formamide; and similar. Flocculants are usually polyelectrolytes of high molecular weight. Materials in commercial use include anionic materials, cationic materials, amphoteric polymers, as well as mixtures of anionic and cationic copolymers. It is also observed that the homopolymers of the anionic or cationic monomer also act as flocculants. The general structure of the synthetic polyelectrolytes used in the present invention is provided in Formulas II, III and IV. N represents a nonionic polymeric segment. A represents an anionic polymer segment. C represents a cationic polymer segment. [N-co-C] (Formula II) [N-co-A] (Formula III) [N-co-C-co-A] (Formula IV) The N segment of the non-ionic polymer in Formula II, Formula III and Formula IV is the repeating unit formed after the polymerization of one or more non-ionic monomers. Exemplary monomers encompassed by N include, but are not limited to, acrylamide; methacrylamide; N-alkyl acrylamides, such as N-methylacrylamide; N, N-dialkylacrylamide, such as N, N-dimethylacrylamide; methyl methacrylate; methyl acrylate; N-vinyl formamide acrylonitrile, N-vinylpyrrolidone, mixtures of any of the foregoing and the like. Other types of nonionic monomer can be used. The segment C of cationic polymer in Formula II and Formula IV is the repeating unit formed after the polymerization of one or more cationic monomers. Exemplary monomers encompassed by C include, but are not limited to, ethylenically unsaturated cationic monomers such as the free salts and bases of diallyldialkylammonium halides, such as diallyldimethylammonium chloride; the (meth) acrylates of compounds of dialkylaminoalkyl such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (me) acrylate, (meth) dimethylaminopropyl acrylate, 2-hydroxyethylaminopropyl (meth) acrylate, aminoethyl (meth) acrylate, the N, N-dialkylaminoalkyl (meth) acrylamides, such as N, N-dimethylaminoethylacrylamide and the salt and quaternary groups and mixture of the previous and similar ones. The segment A of anionic polymer in Formula III and Formula IV is the repeating unit formed after the polymerization of one or more anionic monomers. Exemplary monomers encompassed by A include, but are not limited to, acids and free salts of: acrylic acid; methacrylic acid, maleic acid; Itaconic acid; acrylamido glycolic acid; 2-acrylamido-2-methyl-1-propanesulfonic acid; 3-Allyloxy-2-hydroxy-1-propanesulfonic acid; styrenesulfonic acid; vinylsulfonic acid; vinylphosphonic acid; 2-acrylamido-2-methylpropanphosphonic acid; mixtures of any of the foregoing and the like. The molar percentage of N: C of nonionic monomer to cationic monomer of Formula II can fall within the range of about 99: 1 to about 1:99. The molar percentages of N and C should add up to 100%. It should be understood that more than one class of the nonionic monomer may be present in Formula II. It should also be understood that more than one cationic monomer class can be presented in Formula II. The molar percentage of N: A of the nonionic monomer to the anionic monomer of Formula III can fall within the range of about 99: 1 to 1:99. The molar percentages of N and A should add up to 100%. It should be understood that more than one kind of nonionic monomer can be presented in Formula III. It should also be understood that more than one kind of anionic monomer can be presented in Formula III. With respect to the molar percentages of the amphoteric polymers of Formula IV, the minimum amount of each A, N and C is about 1% of the total amount of the monomer used to form the polyelectrolyte. The maximum amount of A, N or C is about 98% of the total amount of the monomer used to form the polyelectrolyte polymer. The molar percentages of A, N and C should add up to 100%. It should be understood that more than one class of the nonionic monomer may be present in Formula IV, more than one class of cationic monomer may be present in Formula IV, and that more than one class of anionic monomer may be present in Formula IV. Examples of cationic polyelectrolytes used as flocculants include, but are not limited to, cationic acrylamide copolymers, such as PerForm® PC8713 and PerForm® PC8138, products of Hercules Incorporated, ILMINGTON, DE; poly (diallyldimethylammonium chloride), such such as PerForm® PC8717, a product of Hercules Incorporated; polyacrylamide reaction product with dimethylamine and formaldehyde known in the art as Mannich reaction products, such as PerForm® PC 8984, a product of Hercules Incorporated; polymer blends of more than one cationic polymer, poly (vinylamine) and the like. It is contemplated that acrylamide-based cationic functionalized polymers can be used as the second component. One exemplary material is Hercobond® 1000, a product of Hercules Incorporated. Examples of anionic polyelectrolytes include, but are not limited to, copolymers of acrylic acid and acrylamide, such as Perform® 8137 and Reten® 1523H, products of Hercules Incorporated. It is contemplated that functionalized anionic polymers based on acrylamide, can be used as the second component. An exemplary material is Hercobond® 2000, a product of Hercules Incorporated. The polyelectrolytes can vary in molecular weight from 50,000 to 50,000,000 and can be linear, branched or dendritic. These vary in charge density from 1 to 99% on a molar basis. Alternatively, as noted above, the second component may be a polyamidoamine-epihalohydrin, polyamine or polyimine resin. Resins are preferred of polyamidoamine-epihalohydrin such as those described in U.S. Patent Nos. 2,926,116 and 2,926,154, which are incorporated herein by reference in their entirety. Preferred polyamidoamine-epihalohydrin resins can also be prepared in accordance with the teachings of U.S. Patent No. 5,614,597 which are incorporated herein by reference in their entirety. As discussed in U.S. Patent No. 5,614,597, these processes typically involve reacting aqueous polyamidoamine with an excess of epihalohydrin to completely convert amine groups into the adducts of polyamidoamine to epihalohydrin. During the reaction, halohydrin groups are added to the secondary amine groups of the polyamidoamine. Polyamidoamine-epihalohydrin resins include polyamidoamine-epichlorohydrins such as those sold by Hercules Incorporated of Wilmington, DE, under various brands. Preferred polyamidoamine-epihalohydrin resins available from Hercules include, but are not limited to KYMENE® resins and HERCOBOND® resins, KYMENE® 557H resin; KYMENE® 557LX2 resin, KYMENE® 557SLX resin; KYMENE® 557ULX resin, KYMENE® 557ULX2 resin; KYMENE® 709 resin; KYMENE® 736 resin; and HERCOBOND® 5100 resin. Of these, the KYMENE® 557H resin and HERCOBOND® 5100 are especially preferred polyamidoamines, available in the form of aqueous solutions, KYMENE® resin 736 (a polyamine) can also be used as component (A). It is expressly contemplated that equivalents to each of the above resins are within the scope of the present invention. A second alternative component of the retention and dewatering system can be a cyclic organic material. One of the unique aspects of these materials is their ability to form a complex with another, usually molecules or low molecular weight ions. These interactions have been called "guest-guest" chemistry, with the cyclic material being the host and the smallest guest molecule forming a complex where a position is assumed within the ring-like "guest". Examples of these compounds, also called macrocyclic compounds, include, but are not limited to, crown ethers, cyclodextrins and macrocyclic antibiotics. Crown ethers are cyclic oligomers of ethylene glycol comprising hydrogen and carbon oxygen. Each oxygen atom binds to two carbon atoms, resulting in the "corona" -like ring. These molecules are such that the atoms of certain metallic elements, such as potassium sodium, bind themselves to the exposed oxygen atoms of the ring, sequestering it. Cyclodextrin are cyclic starch derivatives of natural origin or can be synthesized using enzymes such as cyclomaltodextrin glucosyltransferase. The cyclodextrins of natural origin, refer to alpha, beta and gamma-cyclodextrin. Cyclodextrins form stable complexes with other compounds. The macrocyclic antibiotic is a term given to a series of cyclic compounds with antibiotic activity. Due to their structure, they will selectively combine with the molecules. Exemplary macrocyclic antibiotics include, but are not limited to rifamycin, vancomycin and ristocetin A. The second component of the retention and dewatering system can be added in amounts of up to 20 kg of active material per metric ton of cellulose pulp based on the dry weight of the pulp, with the proportion of the associative polymer to the second component that is 1: 100 to 100: 1. It is contemplated that more than one second component may be used in the system for making paper. Optionally, siliceous materials can be used as an additional component of a retention and dewatering aid for making paper and cardboard. The siliceous material may be any of the materials selected from the group consisting of silica-based particles, silica microgels, amorphous silica, colloidal silica, anionic colloidal silica, silica sols, silica gels, polysilicates, polysilicic acid, and the like. These materials are characterized by the high surface area, high charge density and submicron particle size. This group includes stable colloidal dispersion of spherical amorphous silica particles, referred to in the art as silicas sols. The term "sol" refers to a stable colloidal dispersion of spherical amorphous particles. Silica gels are aggregated chains of three-dimensional silica, each comprising several amorphous silica sol particles which can also be used in retention and dewatering auxiliary systems; the chains can be linear or branched. The sols and silica gels are prepared by polymerizing monomeric silicic acid in a cyclic structure resulting in discrete amorphous silica sols of polysilicic acid. These silica sols can also be reacted to produce a three-dimensional gel network. The various silica particles (sols, gels, etc.) can have a total size of 5-50 mm. Anionic colloidal silica can also be used. The siliceous material can be added to the cellulosic suspension in an amount of at least 0.005 kg per metric ton based on the dry weight of the cellulose suspension. The amount of siliceous material can be as high as 50 kg per metric ton. Preferably, the amount of siliceous material is from about 0.05 to about 25 kg per metric ton. Even more preferably, the amount of siliceous material is about 0.25 to about 5 kg per metric ton based on the dry weight of the cellulose suspension. The amount of siliceous material in relation to the amount of the associative polymer used in the present invention can be about 100: 1 to about 1: 100 by weight, or from about 50: 1 to 1:50 or about 10: 1 to 1: 10 Still other additional components that may be part of the inventive system are aluminum sources such as alum (aluminum sulfate), polyaluminium sulfate, polyaluminium chloride, and aluminum chlorohydrate. The components of a retention and dewatering system can be added substantially at the same time to the cellulosic suspension. The term retention and drainage system is used herein to encompass two or more different materials added to the slurry to make paper to provide improved retention and drainage. For example, the components can be added to the cellulosic suspension separately either at the same stage or dosage point or at different stages or dosing points. When the components of the inventive system are added simultaneously any two or more of the materials may be added as a mixture. The mixture can be formed, in-situ by combining any of two or more of the materials at the dosing point or in the feed line at dosage point. Alternatively, the inventive system comprises a pre-formed mixture of any two or more of the materials. In an alternative form of the invention, the components of the inventive system are added sequentially. A point of shear stress may or may not occur between the points of addition of the components. The components can be added in any order. The inventive system is usually added to the paper process to affect retention and dewatering. The inventive system can be added to the coarse pulp or the thin pulp, preferably the thin pulp. The system can be added to a feed point, or it can be fed separately so that the inventive system is simultaneously fed to two or more separate feed points. Typical pulp addition points include the feed point (s) before the feed pump, after the feed pump and before the pressure screen or after the pressure screen.

EXAMPLES To evaluate the performance of the present invention, a series of dewatering tests were conducted using a synthetic alkaline raw material. This raw material is prepared from coating pulps marketed in dry hardwood or soft wood and water and additional materials. First, the dry-marketed coating pulp of hardwood and softwood are refined separately. These pulps are then combined in a ratio of about 70 weight percent hardwood to about 30 weight percent softwood in an aqueous medium. The aqueous medium used to prepare the raw material comprises a mixture of local hard water and deionized water at a representative hardness. Inorganic salts are added in amounts so that they provide this medium with a total alkalinity of 75 ppm as CaCO3 and hardness of 100 ppm as CaCO3. The precipitated calcium carbonate (PCC) is introduced into the pulp feedstock at a representative weight percentage to provide a final feedstock containing 80% fiber and 20% PCC filler. Dewatering tests were conducted by mixing the raw material with a mechanical mixer at a specific mixer speed, and introducing the various chemical components into the raw material and allowing the individual components to mix for a specific time before the addition of the next component . The specific chemical components and dose levels are described in the data tables. The dewatering activity of the invention was determined using the Candian Standard Freedom (CSF). The CSF test, a commercially available device (Lorentzen &Wettre, Stockholm, Sweden), can be used to determine the proportion of relative dewatering or drain ratio is also known in the art; a standard test method (TAPPI Test Procedure T-227) is typical. The CSF device consists of a dewatering chamber and a funnel that measures the proportion, both mounted on a suitable support. The dewatering chamber is cylindrical, fitted with a perforated screen plate and a hinged plate at the bottom, and with a lid tightly hinged to the vacuum. The proportion measuring funnel is equipped with a lower hole and a side leakage hole. The CSF dewatering tests are conducted with 1 liter of the raw material. The raw material is prepared for the externally described treatment of the CSF device in a square beaker to provide turbulent mixing. Upon completion of the addition of the additives and the mixing sequence, the treated raw material is poured into the dewatering chamber, closing the upper lid, and then immediately opening the lower plate. Water is allowed to drain freely into the proportion measuring funnel; Aqueous flow exceeding that determined by the lower orifice will flow through the side hole and collect in a graduated cylinder. The generated values are described in millimeters (mi) of the filtrate; values Higher quantitative levels represent higher levels of dewatering or drainage. Test samples were prepared as follows: first 5 kg of cationic starch (Stalok® 400, AE., Staley, Decatur, IL) was added to the raw material prepared as described above per metric ton of raw material (dry basis) . The additive (s) of interest, as noted in the tables, are then added. The data in Table 1 illustrate the dewatering activity of various cationic coagulants within the inventive process. PC 1279 is PerForm® PC1279, a branched polyamide; PC 1290 is PerForm® PC1290, a linear polyamine; PC8229 is PerForm® PC8229 and PC8717 is PerForm® ™ PC8717, polymers of diallyldimethylammonium chloride; SP9232 is PerForm® SP9232, an auxiliary retention and dewatering product; and PC8138 is PerForm® PC8138, a cationic polyacrylamide copolymer; all are products of Hercules Incorporated, Wilmington, DE. Polymin® SK is a modified polyethyleneimine from BASF (Ount Olive, NJ). TABLE 1 CORRIDA * Supplement # 2 Kg / MT Supplement # 3 Kg / MT Supplement # 4 Kg / MT CSF (active) (active) (active) 1 None PC 8138 0.2 none 400 2 PC 1279 0.25 PC B13B 0.2 SP 9232 0.2 540 3 PC 1279 0.5 PC 8138 0.2 SP 9232 0.2 610 4 PC 1290 0.25 PC 8138 0.2 SP 9232 0.2 466 5 PC 1290 0.6 PC 8138 0.2 SP 8232 0.2 435 6 PC 822T 0.25 PC 8138 0.2 SP 9232 0.2 465 7 PC 8229 0.5 PC 8138 SP 0.2 0.2 440 9232 8 8717 0.26 PC 8138 PC 9232 0.2 486 0.2 SP 9 0.5 PC 8717 PC 8138 0.2 9232 0.2 465 SP Polymin SK 10 8138 0.2 0.25 PC SP 9232 0.2 660 11 0.5 Polymin SK PC 8138 0.2 9232 0.2 660 SP The data in Table 1 demonstrate the improved dewatering provided by the current invention with the use of a cationic coagulant. Then, a series of dewatering experiments were conducted with cationic polyvinylamine polymers, as shown in Table 2. The materials are as indicated in Table 1, Alum is aluminum sulfate-octadecahydrate as a 50% solution (Delta Chemical Corp., Baltimore, MD). PPD M-1188, PPD M-1189, and PPD M-5088 (Hercules Incorporated, Wilmington, DE) are copolymers of cationic polyvinylamine, prepared by partial hydrolysis of formamide N-vinyl to produce poly (N-vinyl formamide-co-vinylamine ). Table 2 CORRIDA # Supplement Kg / MT Supplement Kg / MT Supplement Kg / MT CSF, mis # 2 (active) # 3 (active) # 4 (active) 1 Alum 2.5 None SP 9232 0.25 520 2 Aium 2.5 PC 8138 0.25 SP 9232 0.25 880 3 Alum 2.5 PC 8138 0.5 SP T232 0.25 688 4 Alum 2.5 PPD M-1188 0.25 SP 9232 0.25 702 5 Alum 2.5 PPD M-1188 0.5 SP T232 0.25 71 B 6 Alum 2.5 PPD M-1189 0.25 SP 9232 0.25 698 7 Alum 2.5 PPD M-1189 0.5 SP 9232 0.25 704 8 Alum 2.5 PPD M-5088 0.25 SP 9232 0.25 716 9 Alum 2.5 PPD M-5088 0.5 SP 9232 0.25 730 The data in Table 2 illustrate the dewatering activity of cationic polyvinylamine copolymers with the current invention. A series of cationic and anionic flocculants are they evaluated immediately, where the density of specific polymeric molar charge and physical form is observed in Table 3. The EM, FO, A and EM flocculants series are products of SNF Floerger (Riceboro, GA), and Superfloc flocculants are products of Cytec Indutries Inc. (West Patterson, NJ). Table 3 Flocculant Load Shape 1 EM140CT Cationic Powder 2 EM240CT Cationic Powder 3 E 340CT Cationic Powder 4 EM440CT Cationic Powder 5 FO4190SH. Cationic Powder 6 FO4290SH Cationic Powder 7 FO4400SH Cationic Powder 8 FO4490SH Cationic Powder 9 AN 910 Anionic powder 10 AN 910 SH Anionic powder 11 AN 910 VHM Anionic powder 12 AN 923 Anionic powder 13 AN 923 SH Anionic powder 14 AN 923 VHM Anionic powder 16 AN 934 Anionic powder 16 AN 934 SH Anionic powder 17 AN 934 VHM Anionic powder 18 AN 945 Anionic powder 19 AN 945 SH Anionic powder 20 AN 945 VHM Anionic powder 21 AN 956 Anionic powder 22 AN 956 SH Anionic powder 23 AN 956 VHM Anionic Powder 24 AN 970 SH Anionic Powder 25 AN 977 VHM Anionic Powder 26 EM 533 Anionic Emulsion 27 EM 533H Anionic Emulsion 28? T30 Anionic Emulsion 29 EM 635 Anionic Emulsion 30 Superfloc 4814 Anionic Emulsion 31 Superfloc 4816 Anionic Emulsion 32 Superfloc 4818 Anionic Emulsion Table 4! RIDA fl Supplement Kg / MT Supplement Kg / MT Supplement Kg / MT CSF, mis # 2 (active) # 3 (active) # 4 (active) 1 Alum 2.5 None SP 9232 0.2 520 2 Alum 2.5 PC 8138 0.2 SP 9232 0.2 688 3 Alum 2.5 EM140CT 0.2 SP 9232 0.2 700 4 Alum 2.5 E 240CT 0.2 SP 9232 0.2 694 5 Alum 2.5 EM340CT 0.2 SP 9232 0.2 714 6 Alum 2.5 EM440CT 0.2 SP 9232 0.2 704 7 Alum 2.5 FO4190SH 0.2 SP 9232 0.2 691 8 Alum 2.5 FO4290SH 0.2 SP 9232 0.2 713 9 Alum 2.5 FO4400SH 0.2 SP 9232 0.2 713 10 Alum 2.5 FO4490SH 0.2 SP 9232 0.2 704 11 Alum 2.5 PA 8137 0.2 SP 9232 0.2 685 12 Alum 2.5 AN 910 0.2 SP 9232 0.2 690 13 Alum 2.5 AN 910 SH 0.2 SP 9232 0.2 682 14 Alum 2.5 AN 910 VHM 0.2 SP 9232 0.2 699 15 Alum 2.5 AN 923 0.2 SP 9232 0.2 678 16 Alum 2.5 AN 923 SH 0.2 SP 9232 0.2 692 17 Alum 2.5 AN 923 VHM 0.2 SP 9232 0.2 688 18 Alum 2.5 AN 934 0.2 SP 9232 0.2 672 19 Alum 2.5 AN 934 SH 0.2 SP 9232 0.2 681 20 Alum 2.5 AN 934 VHM 0.2 SP 9232 0.2 666 21 Alum 2.5 AN 945 0.2 SP 9232 0.2 668 22 Alum 2.5 AN 945 S H 0.2 SP 9232 0.2 659 23 Alum 2.5 AN 945 VHM 0.2 SP 9232 0.2 676 24 Alum 2.5 AN 956 0.2 SP 9232 0.2 680 25 Alum 2.5 AN 956 SH 0.2 SP 9232 0.2 673 26 Alum 2.5 AN 956 VHM 0.2 SP 9232 0.2 675 27 Alum 2.6 AN 970 SH 0.2 SP 9232 0.2 666 28 Alum 2.6 AN 977 VHM 0.2 SP 9232 0.2 T60 29 Alum 2.5 EM 533 0.2 SP 9232 0.2 671 30 Alum 2.5 EM 533H 0.2 SP 9232 0.2 678 31 Alum 2.5 EM 630 0.2 SP 9232 0.2 670 32 Alum 2.5 E 635 0.2 SP 9232 0.2 659 33 Alum 2.5 Superfloc 814 0.2 SP 9232 0.2 680 34 Alum 2.5 Supertloc 4816 0.2 SP 9232 0.2 686 35 Alum 2.5 Superfloc 4818 0.2 SP 9232 0.2 682 improved activity when cationic or anionic flocculants are used within the present invention. Table 5 illustrates the usefulness of cyclic organic materials. Test samples were prepared as follows: the raw material is added as described above, first 5 kg of cationic starch (Stalok® 400, AE. , Staley, Decatur, IL) per metric ton of raw material (dry basis), then 2.5 kg of alum (aluminum sulfate-octadecahydrate obtained from Delta Chemical Corporation, Baltimore, D as a 50% solution) per metric ton of material premium (dry basis) and then 0.5 kg of PerForm® PC8138 (Hercules Incorporated, ilmington, DE) per tonne of raw material (dry basis). The additive (s) of interest, as shown in the table, were then added in the examples provided in the table. SP9232 is PerForm® SP9232, a retention and dewatering aid produced under certain conditions (see PCT O 03/050152 A), is a product of Hercules Incorporated, Wilmington, DE; silica is colloidal silica BM 780, a product of Eka Chemicals, Marieta, GA, crown ether is a compound of 15-crown-5 (1, 4, 7, 10, 13 -pentaoxaciclopentadecane) obtained from Aldrich Chemicals, Milwaukee, WI , and CD is alpha-cyclodextrin hydrate obtained from Aldrich Chemical, Milwaukee, WI. The data indicates that the cyclic organic compounds provide improved dewatering.

Table 5 SP9232 and silica aggregates at a level of 0.25 kg per metric ton of raw material (dry basis), crown ether and CD are added at a level of 0.5 kg per metric ton of raw material (dry basis). < b) SIM indicates simultaneous addition and SEQ indicates sequential addition.

Claims (22)

1. CLAIMS 1. A method for improving retention and dewatering in a papermaking process wherein the improvement comprises adding to a paper making slurry, an associative polymer and at least one synthetic polyelectrolyte, wherein the associative polymer comprises the formula: tB- co-Ff (I) wherein B is a nonionic polymer segment comprising one or more nonionic ethylenically unsaturated monomers; F is a polymeric segment comprising at least one anionic ethylenically unsaturated or ethylenically unsaturated cationic monomer; and the molar percent ratio of B: F is 99: 1 to 1:99 and wherein the associative polymer has associative properties provided by an effective amount of at least one emulsifying surfactant chosen from either diblock or triblock polymeric surfactants , and wherein the amount of at least one diblock or triblock to monomer surfactant is at least about 3: 100, wherein at least one synthetic polyelectrolyte is selected from the group consisting of cationic copolymers with 20 mole percent or greater content of cationic monomer, an anionic copolymer with 20 mole percent or less anionic monomer content, polyamines, polychlorides diallyldimethylammonium, polyamidoamine-epichlorohydrin resins, or modified polyethyleneimines. The method of claim 1, wherein at least one synthetic polyelectrolyte is selected from the group consisting of cationic copolymers with 20 mole percent or higher cationic monomer content; and an anionic copolymer with 20 mole percent or less anionic monomer content; and wherein the cationic or anionic copolymer comprising at least one nonionic monomer selected from acrylamide, methacrylamide, N, N-dialkylacrylamides, N-alkyl acrylamides, N-vinyl metacetamide, N-vinylformamide, N-vinylmethylformamide, and N-vinylpyrrolidone. 3. The method of claim 2, wherein at least one synthetic polyelectrolyte is an anionic copolymer with 20 mole percent or less anionic monomer content wherein the anionic copolymer comprises at least one anionic monomer selected from the acid or free salt; acrylic acid; methacrylic acid, maleic acid; Itaconic acid; acrylamido glycolic acid; 2-acrylamido-2-methyl-1-propanesulfonic acid; 3-Allyloxy-2-hydroxy-1-propanesulfonic acid; styrene-phonic acid; vinylsulfonic acid; vinylphosphonic acid; 2-acrylamido-2-methylpropanphosphonic acid. 4. The method of claim 3, wherein the less a synthetic polyelectrolyte is an anionic copolymer with 20 mole percent or less anionic monomer content wherein the anionic copolymer comprises at least one anionic monomer selected from the acid or free salt; Acrylic acid, methacrylic acid and styrenesulfonic acid. The method of claim 2, wherein at least one synthetic polyelectrolyte is a cationic copolymer with 20 mole percent or higher cationic monomer content wherein the cationic copolymer comprises at least one cationic monomer selected from the base or salt free; diallyldimethylammonium halide; dialkylaminoalkyl (meth) acrylate; (meth) diethylaminoethyl acrylate, aminopropyl (meth) acrylate, 2-hydroxydimethylaminopropyl (meth) acrylate, aminoethyl (meth) acrylate, N, N-dimethylaminoethylacrylamide and acryloyloxyethyltrimethylammonium chloride. The method of claim 5, wherein at least one synthetic polyelectrolyte is a cationic copolymer with 20 mole percent or higher cationic monomer content wherein the cationic copolymer comprises at least one cationic monomer selected from the base or free salt from; N, N-dimethylaminoethylacrylamide and acryloyloxyethyl trimethylammonium chloride. The method of claim 1, wherein at least one synthetic polyelectrolyte is selected from the group consisting of polyamidoamine-epihalohydrin resins; polyamines; polyimines; and derivatives of any of the foregoing. The method of claim 7, wherein at least one synthetic polyelectrolyte comprises polyamidoamine-epihalohydrin resins or derivatives thereof. 9. The method of claim 1, further comprising a siliceous material. The method of claim 9, wherein the siliceous material is selected from the group consisting of silica-based particles, silica microgels, amorphous silica, colloidal silica, anionic colloidal silica, silica sols, silica gels, polysilicates, polysilicic acid and combinations thereof. The method of claim 1, wherein at least one synthetic polyelectrolyte comprises a polyamine or derivatives thereof. 12. The method of claim 1, wherein the associative polymer is anionic. The method of claim 1, wherein the associative polymer comprises acrylamide and acrylic free acid or salt. 14. A composition comprising an associative polymer and at least one synthetic polyelectrolyte wherein the associative polymer comprises the formula: t-B-co-Ff (1) wherein B is a nonionic polymer segment comprising one or more nonionic ethylenically unsaturated monomers; F is a polymer segment comprising at least one ethylenically unsaturated or ethylenically unsaturated cationic anionic monomer; and the molar percent ratio of B: F is 99: 1 to 1:99 and wherein the associative polymer has associative properties provided by an effective amount of at least one emulsifying surfactant chosen from diblock polymeric surfactants or triblock, and wherein the amount of at least one diblock or triblock to monomer surfactant is at least about 3: 100, wherein at least one synthetic polyelectrolyte is selected from the group consisting of 20 mole percent cationic copolymers or higher cationic monomer content, an anionic monomer copolymer with 20 mole percent or less anionic monomer content, polyamines, poly-diallyldimethylammonium chlorides, polyamidoamine-epichlorohydrin resins or modified polyethyleneimines. 15. The composition of claim 14, further comprising cellulosic fiber. 16. The composition of claim 14, wherein at least one synthetic polyelectrolyte is selected from group consisting of cationic copolymers with 20 mole percent or higher cationic monomer content; and an anionic copolymer with 20 mole percent or less anionic monomer content; and wherein the cationic or anionic copolymer comprises at least one nonionic monomer selected from acrylamide, methacrylamide, N, N-dialkylacrylamides, N-alkyl acrylamides, N-vinyl methacetamide, N-vinylformamide, N-vinylmethylformamide and N-vinylpyrrolidone. The composition of claim 16, wherein at least one synthetic polyelectrolyte is an anionic copolymer with 20 mole percent or less anionic monomer content wherein the anionic copolymer comprises at least one anionic monomer selected from the acid or free salt; acrylic acid; methacrylic acid, maleic acid; Itaconic acid; acrylamido glycolic acid; 2-acrylamido-2-methyl-l-propanesulfonic acid; 3-allyloxy-2-hydroxy-l-propanesulfonic acid; styrenesulfonic acid; vinylsulfonic acid; vinylphosphonic acid; 2-acrylamido-2-methylpropanphosphonic acid. The composition of claim 17, wherein at least one synthetic polyelectrolyte is an anionic copolymer with 20 mole percent or less anionic monomer content wherein the anionic copolymer comprises at least one anionic monomer selected from the acid or salt free of: acrylic acid, methacrylic acid and acid is ionic phonic. The composition of claim 16, wherein at least one synthetic polyelectrolyte is a cationic copolymer with 20 mole percent or higher cationic monomer content wherein the cationic copolymer comprises at least one cationic monomer selected from the base or free salt of: diallyldimethylammonium halide; dialkylaminoalkyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, 2-hydroxydimethylaminopropyl (meth) acrylate, aminoethyl (meth) acrylate, N, N-dimethylaminoethylacrylamide and acryloyloxyethyltrimethylammonium chloride. The composition of claim 19, wherein at least one synthetic polyelectrolyte is a cationic copolymer with 20 mole percent or higher cationic monomer content wherein the cationic copolymer comprises at least one cationic monomer selected from the base or free salt of: N, N-dimethylaminoethylacrylamide, and acryloyloxyethyltrimethylammonium chloride. The composition of claim 14, wherein at least one synthetic polyelectrolyte is selected from the group consisting of polyamidoamine-epihalohydrin resins; polyamines; polyimines; and derivatives of any of the foregoing. 22. The composition of claim 14, wherein at least one synthetic polyelectrolyte comprises polyamidoamine-epihalohydrin resins or derivatives thereof.