Debonders for Use in Papermaking

Abstract

Debonding compositions and methods are disclosed for use in fibrous compositions such as paper-based products. In some instances, debonding agents can be combined with fibers (e.g., cellulose-based fibers) to produce a material having substantial wicking properties while decreasing fiber-fiber interactions that can require substantial energy to overcome in materials processing. In some instances, the debonding agent can act to create a paper-based product exhibiting a transition temperature in which the agent has a higher affinity for the fibers at temperatures above the transition temperature, and the product exhibiting enhanced wicking properties at temperatures below the transition temperature. As an example, a debonding agents can include polymers or other material exhibiting a lower critical solution temperature. The disclosed debonding agents can provide benefits over existing debonding agent formulations such as ammonium salts.

1 . A fiber-containing composition suitable for use to improve fluid distribution, comprising:
 a fibrous material comprising fibers; and   a debonding agent comprising a polymer composition exhibiting a lower critical solution temperature (LCST), the fiber-containing composition exhibiting a transition temperature such that   (i) the debonding agent has a higher affinity for the fibers when the temperature is above a transition temperature relative to when the temperature is below the transition temperature; and   (ii) the debonding agent enhances fluid distribution in the fiber-containing composition when the temperature of the debonding agent is below the transition temperature relative to when the temperature is above the transition temperature.   
     
     
         2 . The fiber-containing composition of  claim 1 , wherein the fiber-containing composition is substantially free of ammonium salt in an amount capable of substantially affecting wicking of the fiber-containing composition. 
     
     
         3 . The fiber-containing composition of  claim 1 , wherein the polymer composition comprises a copolymer. 
     
     
         4 . The fiber-containing composition of  claim 1 , wherein the polymer composition comprises a blend of different polymer molecules. 
     
     
         5 . The fiber-containing composition of  claim 1 , wherein the debonding agent comprises a plurality of alkylene oxide units. 
     
     
         6 . The fiber-containing composition of  claim 5 , wherein the debonding agent comprises at least one of polyethylene oxide units and polypropylene oxide units. 
     
     
         7 . The fiber-containing composition of  claim 5 , wherein the debonding agent comprises a polymer with two distinct alkylene-oxide units, each alkylene-oxide unit exhibiting a different LCST at a given concentration and molecular weight distribution. 
     
     
         8 . The fiber-containing composition of  claim 1 , wherein the debonding agent is substantially free of a charged specie. 
     
     
         9 . The fiber-containing composition of  claim 1 , wherein the transition temperature is between about 5° C. and about 95° C. 
     
     
         10 . The fiber-containing composition of  claim 1 , further comprising:
 a transition temperature modifier capable of changing the LCST of the polymer composition, the transition temperature-modifier comprising at least one of a chaotropic salt and a surfactant.   
     
     
         11 . The fiber-containing composition of  claim 1 , wherein the fiber-containing composition is at least a portion of an absorbent fiber-based article. 
     
     
         12 . A method of improving wicking of a fiber-based material comprising:
 providing a fiber-containing composition comprising a polymeric debonding agent disposed with a plurality of fibers, a polymer of the polymeric debonding agent exhibiting lower critical solution temperature (LCST) behavior; and   subjecting the fiber-containing composition to a temperature below a transition temperature such that the fiber-containing composition exhibits enhanced wicking relative to a fiber-containing composition without the debonding agent.   
     
     
         13 . The method of  claim 12 , wherein the fiber-containing composition is substantially free of ammonium salt in an amount capable of substantially affecting wicking of the fiber-containing composition. 
     
     
         14 . The method of  claim 12 , wherein the polymeric debonding agent comprises a copolymer. 
     
     
         15 . The method of  claim 12 , wherein the polymeric debonding agent comprises a blend of different polymer molecules. 
     
     
         16 . The method of  claim 12 , wherein the debonding agent comprises a plurality of alkylene oxide units. 
     
     
         17 . The method of  claim 12 , wherein the debonding agent is substantially free of a charged specie. 
     
     
         18 . The method of  claim 12 , wherein the fiber-containing composition comprises a transition temperature-modifier capable of changing the transition temperature of the debonder agent in the fiber-containing composition, the transition temperature-modifier comprising at least one of a chaotropic salt and a surfactant. 
     
     
         19 . The method of  claim 12 , wherein the step of providing the fiber-containing composition comprises:
 forming a mixture comprising at least a portion of the fiber-containing composition at a temperature below the transition temperature; and   drying the mixture to provide the fiber-containing composition.   
     
     
         20 . The method of  claim 19 , wherein the step of forming the mixture comprises:
 forming the mixture with the debonding agent.   
     
     
         21 . The method of  claim 19 , further comprising:
 applying the debonding agent while the mixture is being dried.   
     
     
         22 . The method of any one of  claim 19 , wherein the step of drying the mixture comprises subjecting the mixture to a temperature above the transition temperature. 
     
     
         23 . The method of  claim 22 , wherein the step of drying comprises:
 using the debonding agent to inhibit hydrogen bonding between at least some fibers during the step of drying.   
     
     
         24 . The method of  claim 12 , wherein the method is used to form an absorbent fiber-based article. 
     
     
         25 . A method of utilizing a debonder in a paper-based composition, comprising:
 inserting a debonder composition in a paper-based mixture including fibers, the debonder composition comprising:   (i) at least one polymeric component exhibiting a lower critical solution temperature (LCST), and   (ii) at least one modifying component, the modifying component selected to alter the LCST of the at least one polymeric component so that the altered LCST falls within a temperature range between about 5° C. and about 95° C.   
     
     
         26 . The method of  claim 25 , wherein the at least one polymeric component comprises a first block of a copolymer. 
     
     
         27 . The method of any one of  claim 26 , wherein the at least one modifying component comprises a second block of the copolymer. 
     
     
         28 . The method of  claim 27 , wherein the copolymer comprises a plurality of alkylene-oxide unit types. 
     
     
         29 . The method of  claim 28 , wherein the plurality of alkylene-oxide unit types comprises at least one of an ethylene-oxide and a propylene oxide. 
     
     
         30 . The method of  claim 25 , wherein the at least one polymeric component comprises a first polymer comprising a repeat unit, and the at least one modifying component comprises a second polymer comprising a different repeat unit. 
     
     
         31 . The method of  claim 30 , wherein the repeat unit type comprises an alkylene-oxide unit type, and the different repeat unit type comprises a different alkylene-oxide unit type. 
     
     
         32 . The method of  claim 25 , wherein the at least one polymeric component comprises a first polymer characterized by a first repeat unit and the at least one modifying comprises a second polymer characterized by the first repeat unit, the first polymer and the second polymer differing in at least one of molecular weight, branching, and the first polymer having a second repeat unit not present in the second polymer. 
     
     
         33 . The method of  claim 25 , wherein the at least one modifying component comprises a chaotropic salt. 
     
     
         34 . The method of  claim 25 , further comprising:
 maintaining the paper-based mixture at a temperature above a transition temperature to inhibit adhesion between at least a plurality of fibers of the paper-based mixture.   
     
     
         35 . The method of  claim 34 , further comprising:
 maintaining the paper-based mixture at a temperature below the transition temperature such that the at least one polymeric component exhibits hydrophilic behavior.   
     
     
         36 . The method of  claim 25 , wherein the debonding composition is substantially free of a charged specie.