A papermaking method comprises providing a slurry having fibrous material, extruded starch and optionally an inorganic filler. The slurry is pressed to a minimum solids content before drying. The extruded starch may a) be cationic, b) be chemically or enzymatically modified, c) be non-crosslinked, d) have a solubility in the range of 40–99%, e) have a molecular weight greater than 300,000 Da, f) have a weight fraction greater than 30,000,000 Da of 0.05 or less, and/or g) have an RVA viscosity of 15,000 cP or less. Feed starch is extruded with water. Optionally, one or more of a polyol, humectant or plasticizer may be added. Optionally, a chemical reagent or enzyme is used during extrusion to modify the starch. Optionally, extrusion is carried out substantially in the absence of a crosslinking agent. Extrusion may be carried out in a twin-screw extruder, optionally having one or more high-shear sections.
Country Code: CA
Application Number: CN202380032870.4
