A research team at North Carolina State University says biobased glucaric-acid or lignin additives can dramatically increase the toughness of polyvinyl alcohol fibers.
As a new anti-plasticizer, the additive can nearly triple the resin's tensile strength and double its modulus, and the enhanced PVA fibers can find uses in biofriendly products such as fibers and polymers, detergents, paints and diapers.
Currently, glucaric acid is used often as an ingredient in nutraceutical supplements. The aromatic organic polymer lignin is a waste by-product of the pulp and paper industry.
Biotechnology startup Kalion Inc. of Milton, Mass., provided glucarate-acid salts for the university's research. Kalion obtained the compound through its partnership with the University of Georgia bio-expression and fermentation facility in Athens, Ga.
N.C. State University researchers Ericka Ford and Chunhong Lu demonstrated that glucaric-acid salts can anti-plasticize the gel spinning of PVA fibers, enhancing the material's melting point, processing conditions and structural and mechanical properties.
Ford is an assistant professor in textile technology in the N.C. State's department of textile engineering, chemistry and science in Raleigh.
Lu received her doctorate from NC State in December 2017 and lectures now in the department of textile engineering at Donghua University in Shanghai.
Ford had the original idea in early 2017. She said via email: "The ... team uses the gel spinning technique to form fibers from polymers that can extend to high-draw ratios. Our team is always in search of ways to enhance fiber drawing through chemical processes that do not compromise fiber strength."
"At low-weight percentages, glucaric acid seemed to be a plausible additive for the spinning of PVA fibers because of its hydroxyl groups. Its chemistry was also believed to engage in strong hydrogen bonding with drawn matrix polymer without hindering PVA crystallization," Ford added.
Grants from the Nonwovens Institute and the National Science Foundation supported the research.
John Wiley & Sons Inc. of Hoboken, N.J., posted the researchers' technical paper Feb. 21 and published it in the April issue of the journal Macromolecular Materials and Engineering.