Abstract: The disclosure provides methods and compositions for coating substrates. A method of coating a substrate may include applying a formulation having a metal cation to a surface of the substrate to form a treated substrate, adding a solution having a biopolymer to the treated substrate, and allowing the biopolymer and the metal cation to react to form a coated substrate. The formulation may be applied to the substrate before the solution is added. A composition may include a reaction product of a biopolymer and a metal cation. The reaction product may be disposed on a coated substrate and the coated substrate may comprise a fibrous material.

Abstract: Biocide can be controllably added to a feed stream for a membrane. The membrane can separate the feed stream into a purified permeate stream and a concentrate stream containing contaminants from the feed stream. In some examples, a charge neutral biocide is introduced into the feed stream at a first addition rate. The concentration of the charge neutral biocide in the permeate stream is measured to provide a measured concentration of the charge neutral biocide in the permeate stream. The addition rate of the charge neutral biocide can be adjusted based on the measured concentration of the charge neutral biocide in the permeate stream to introduce charge neutral biocide into the feed stream at a second addition rate different than the first addition rate.

Abstract: Biocide can be controllably added to a feed stream for a membrane. In some examples, the feed stream is separated into a primary feed stream and a secondary feed stream, for example, with the secondary feed stream having a lower flow rate than the primary feed stream. The secondary feed stream may be used to monitor and control the addition of the biocide, which is then diluted when the secondary feed stream is combined with the primary feed stream to form a combined stream for delivery to the membrane.

Abstract: Hydrophilic cationic dispersion polymers, compositions including same, and methods of using same. In some examples, a composition can include a hydrophilic cationic dispersion polymer disposed on a surface of a substrate. The substrate can be a paper, a textile, a non-woven material, a film, or mixtures thereof. The hydrophilic cationic dispersion polymer can include repeating units derived from a first monomer and a second monomer. The first monomer can be a nonionic monomer and the second monomer can be at least one hydrophilic cationic monomer selected from a diallyl-N,N-dimethylammonium halide and a monomer of the formula I: where A1 can be O or NH; B1 can be a C2-C4 alkylene or hydroxypropylene; R1 can be H or CH3; R2 and R4 can independently be a C1-C2 alkyl; R3 can be H or a C1-C2 alkyl; and X1 can be an anionic counterion.

Abstract: Biocide can be controllably added to a feed stream for a membrane. The membrane can separate the feed stream into a purified permeate stream and a concentrate stream containing contaminants from the feed stream. In some examples, a charge neutral biocide is introduced into the feed stream at a first addition rate. The concentration of the charge neutral biocide in the permeate stream is measured to provide a measured concentration of the charge neutral biocide in the permeate stream. The addition rate of the charge neutral biocide can be adjusted based on the measured concentration of the charge neutral biocide in the permeate stream to introduce charge neutral biocide into the feed stream at a second addition rate different than the first addition rate.

Abstract: Biocide can be controllably added to a feed stream for a membrane. In some examples, the feed stream is separated into a primary feed stream and a secondary feed stream, for example, with the secondary feed stream having a lower flow rate than the primary feed stream. The secondary feed stream may be used to monitor and control the addition of the biocide, which is then diluted when the secondary feed stream is combined with the primary feed stream to form a combined stream for delivery to the membrane.

Abstract: A method of monitoring and controlling one or more types of hydrophobic contaminants in a papermaking process is disclosed. The methodology utilizes the measurement of dyes, which are capable of fluorescing and interacting with the hydrophobic contaminants.

Abstract: A method of monitoring and controlling one or more types of hydrophobic contaminants in a papermaking process is disclosed. The methodology utilizes the measurement of hydrophobic dyes, which are capable of fluorescing and interacting with the hydrophobic contaminants. In addition, a method of determining the relative size of the hydrophobic contaminants is disclosed as well.

Abstract: A method of preparing a modified diallyl-N,N-disubstituted ammonium halide polymer and use of the polymer in combination with one or more high molecular weight, water soluble cationic, anionic, nonionic, zwitterionic or amphoteric polymers for increasing retention and drainage in a papermaking furnish.

Abstract: A method of preparing a modified diallyl-N,N-disubstituted ammonium halide polymer and use of the polymer in combination with one or more high molecular weight, water soluble cationic, anionic, nonionic, zwitterionic or amphoteric polymers for increasing retention and drainage in a papermaking furnish.

Abstract: A method of preparing a modified diallyl-N,N-disubstituted ammonium halide polymer and use of the polymer in combination with one or more high molecular weight, water soluble cationic, anionic, nonionic, zwitterionic or amphoteric polymers for increasing retention and drainage in a papermaking furnish.

Abstract: An improved papermaking process comprising forming an aqueous coated broke papermaking slurry and adding a blend of a water-soluble dispersion polymer and a coagulant to the slurry to increase retention and/or drainage is disclosed. After addition of the polymers, the slurry is drained to form a sheet, and the sheet is dried.