Bioproduction of Super Absorbent Polymers

Super absorbent polymers (SAPs) are crosslinked polymer chains that absorb and retain extremely large amounts of a liquid relative to their own mass. Crosslinked poly(acrylic acid) (PAA) is by far the largest amount of SAP commercially manufactured and used today, where the most prominent use of PAA-based SAPsisinthemanufacturingofpersonal disposable hygiene productssuchasbaby diapers, adultdiapers and sanitary napkins. The global market for SAPs is ~$9 billion/yr, of which at least $7 billion/yr comprises of SAPs used in disposable personal hygiene applications. Despite their broad use, PAA-based SAPs have a multitude of issues including but not limited to sustainability concerns surroundingthe production processes of these petroleum-based SAPs, toxicity concerns stemming from the acrylamide of PAA-based SAPs in the hygiene products, and the lack of both biodegradability and recyclability of the PAA- based SAP, resulting in the need for disposal via incineration or landfilling. The scale of this global problem is immense, with U.S. consumption alone equating to ~30 billion disposable diapers/yr, which accounts for ~8% (~4 million MT/yr) of all municipal solid waste in domestic landfills. This global problem continues to accelerate at an alarming rate fueled by population growth, especially in developing countries. ZymoChem’s conversations with leading global hygiene product manufacturers and brand owners have re-confirmed firsthand the dire need within this industry to develop & commercialize more sustainable and eco-friendly products, specifically ‘drop-in’ bio-based and biodegradable SAPs as soon as possible. To enable a more circular hygiene industry, ZymoChem is developing low-cost, environmentally safe, biodegradable, recyclable, and high-performance bio-based SAPs that can be made using lignocellulosic feedstocks. Our ‘Bio-SAPs’ will be ~100% bio-based and also fully biodegradable, wherein the production of our Bio-SAPs is accomplished in two steps. First, a non-toxic, Bio-SAP-precursor is produced via microbial fermentation and using lignocellulosic feedstocks. Second, the Bio-SAP-precursor is converted into the Bio- SAP via ZymoChem’s proprietary chemical technology, which utilizes sustainable processes and/or chemical ingredients that can be produced from renewable/bio-based sources. Prior to the SBIR Phase I project, ZymoChem had already developed a bioprocess for making its Bio-SAP-precursor near commercially relevant fermentation metrics. During the Phase I project, ZymoChem successfully established its chemical technology by developing bio-based SAP materials with performance characteristics that matched/exceeded those of the commercial PAA-based SAPs derived from actual mainstream consumer products. The goals of this Phase II project are three-fold. First, ZymoChem will optimize its chemical technology to concurrently improve the Bio-SAP’s performance metrics and lower overall production costs for the commercial scale process. Second, ZymoChem will scale its fully integrated process for making the Bio-SAP- precursor and then the purified Bio-SAP to generate sufficient material for the third goal of the project – manufacturing prototypes of the Bio-SAPs’ end-use application(s) for testing purposes. At the end of thisPhase II project, ZymoChem aims to be ~1 year away from demonstrating its fully integrated process with a CMO facility in order to produce its Bio-SAP at/near commercial scale.