** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THE SUCCESSFUL IMPLEMENTATION OF BIOREFINERIES IS NECESSARY TO STRENGTHEN THE U.S. BIOECONOMY AND INCREASE U.S. ENERGY SECURITY. LIGNIN IS THE SECOND MOST ABUNDANT BIOPOLYMER IN NATURE AFTER CELLULOSE, MAKING UP ROUGHLY 25 TO 40 WT% OF FOREST BIOMASSES. HOWEVER, LIGNIN IS CURRENTLY UNDERUTILIZED IN BIOREFINERIES, WHICH LIMITS THE COMMERCIALIZATION OF NEW FOREST BIOREFINERIES AND AFFECTS THE REVENUES OF PULP AND PAPER BIOREFINERIES IN THE UNITED STATES. SINCE ABOUT 25 TO 40 WT% OF THE WOODY BIOMASS IN MOST BIOREFINERIES IS OFTEN LEFT AS A BY-PRODUCT (E.G., BIOCHAR OR LIGNIN), FINDING A SUSTAINABLE SOLUTION IS CRUCIAL FOR ADVANCING NEW BIOREFINERY TECHNOLOGIES. ADDITIONALLY, DECLINING REVENUES IN PULP AND PAPER FACILITIES COULD BE MITIGATED BY CREATING NEW REVENUE STREAMS USING KRAFT LIGNIN TO PRODUCE HIGH-VALUE COMPOSITES. HOWEVER, THE USE OF LIGNIN IN THE PRODUCTION OF HIGH VALUE-ADDED RENEWABLE COMPOSITES IS LIMITED BECAUSE ITS STRUCTURE IS COMPLEX, AND IT DOESN'T HAVE THE FIBROUS FORM NEEDED FOR THESE PRODUCTS. THIS GRANT WILL HELP US TO DEVELOP NEW AND COST-EFFECTIVE METHODS TO PRODUCE DIFFERENT TYPES OF LIGNIN WITH ADJUSTABLE PROPERTIES (LIKE SIZE AND STRUCTURE) TO ENHANCE ITS APPLICATION IN THE PRODUCTION OF LIGNIN CONTAINING CELLULOSE NANOFIBRILS (LCNF) COMPOSITES.RECENT ADVANCES IN THE USE OF CELLULOSE NANOFIBRILS (CNFS) TO MAKE SUSTAINABLE POLYMER COMPOSITES HAVE DEMONSTRATED THE POTENTIAL TO REVOLUTIONIZE THE U.S. BIOECONOMY AND MAINE'S FOREST BIO-PRODUCT INDUSTRY. SINCE CNFS NATURALLY ATTRACT WATER, THEY DON'T MIX WELL WITH PLASTIC-LIKE MATERIALS THAT REPEL WATER. THIS CHALLENGE WITH THE CNF CAN BE OVERCOME WITH THE PRODUCTION OF LCNF, WHICH WILL IMPROVE THE HYDROPHOBICITY OF CNF WHILE PROVIDING A MARKET FOR LIGNIN. CURRENT RESEARCH IS FOCUSED ON PRODUCING LCNF DIRECTLY FROM PARTIALLY DELIGNIFIED FIBERS CONTAINING RESIDUAL LIGNIN CONTENT. THIS APPROACH WOULD LIMIT THE AMOUNT OF LIGNIN TO LESS THAN 1 WT% IN THE PRODUCTION OF LCNF DERIVED THERMOPLASTIC COMPOSITES. AS AN ALTERNATIVE, WE WILL PRODUCE LCNF FROM SEPARATED LIGNIN (SUCH AS KRAFT LIGNIN) AND ADJUST ITS PROPERTIES, ALONG WITH THE AMOUNT OF LIGNIN ON THE SURFACE OF CNF PARTICLES, TO IMPROVE ITS COMPATIBILITY WITH PLASTIC MATERIALS. THE SUCCESSFUL FORMULATION OF LCNF-REINFORCED THERMOPLASTIC COMPOSITES CAN YIELD ENHANCED MECHANICAL AND VISCOELASTIC PROPERTIES CAPABLE OF REDUCING THE U.S. DEPENDENCE ON THE NON-RENEWABLE PETROLEUM FEEDSTOCK TO PRODUCE BUILDING AND PACKAGING MATERIALS AND INCREASING THE PROFITABILITY OF FOREST BIOREFINERIES.