Advances in the Use of Protein-Based Materials: Toward Sustainable Naturally Sourced Absorbent Materials

Superabsorbent polymers (SAPs) are important in the health-care and personal care industries. Products like bed pads and diapers improve the comfort and sanitary conditions for people all over the world, with SAPs reaching yearly production volumes of ca. 2 million tons. However, recent sustainability issues have questioned the high negative footprint of polymers from nonrenewable resources. Biomacromolecules, especially when functionalized, have properties that make them an attractive alternative for the production of biobased SAPs. Proteins are a particularly interesting alternative due to their high variability and because of their relatively low price, being available as side streams from the agricultural industries. Due to the harsh extraction conditions, these side stream proteins are not competing with the food industry and alternative source-effective uses are advantageous in a circular bioeconomy. As the properties of a SAP material come from a combination of neutralized functional groups to prom...