Graft copolymers of collagen and acrylic monomers—Reagents for sizing of cotton yarn

Abstract

A new highly effective sizing reagent based on grafted collagen copolymers has been proposed for cotton yarn. The copolymers were synthesized by reacting an aqueous solution of collagen with acrylic monomers—acrylic, matacrylic acids, and their amides in the presence of potassium persulfate. Based on Scanning electron microscopy ‐ Energy dispersive (SEM‐EDS) analysis data, the composition of the copolymers was determined. Unsaturated acids are more actively grafted onto collagen than their amides. When a polymer film is formed from a solution of a collagen copolymer with (meth)acrylic acid, microcracks appear on the surface of the sample; microcracks are absent in films of copolymers with (meth)acrylamide. Films of copolymers, especially methacrylamide, are quite flexible and contribute to a significant improvement in the properties of the yarn. The tensile strength of yarn sized with copolymers increases by 20%–65% compared to unsized yarn, and by 13%–38% compared to yarn sized with a starch solution. At the same time, the relative tensile elongation of the experimental yarn improves by 14%–58%, while this property of starch‐size yarn deteriorates by 14%–22% compared to unsized yarn. The complete removal of graft copolymers from the surface of the yarn in the process of biochemical desizing using the enzyme protease is shown.Highlights Graft copolymerization of (meth)acrylamide with collagen was carried out. Grafting is initiated by the interaction of collagen with potassium persulfate. The synthesized copolymers are effective sizing reagents for cotton yarn. The copolymer with poly(meth)acrylamide forms a flexible and stable film. The protease enzyme completely removes the size from the surface of the yarn.