Eco-friendly production of cellulose nanocrystals from corn straw through combined enzyme pretreatment, mild homogenization, and enzymolysis

The use of friendly processes to produce cellulose nanocrystals (CNCs) from agricultural waste is an important way towards achieving sustainability in biomass refining. In this work, CNCs were extracted from corn straw through an efficient process that combines enzyme pretreatment, mild homogenization, and enzymolysis. The yield of CNCs reached 40.3 %, which is notable for enzymatic hydrolysis methods. The as-prepared CNCs, with a length range of 300–900 nm, exhibit high crystallinity (72 %–76 %) and good thermal stability ( T on = 194–210 °C, T max = 327–343 °C), and still maintain the crystal structure of cellulose I β . An application attempt involved constructing a composite film using as-prepared CNCs and polyvinyl alcohol (PVA). The CNCs/PVA composite film demonstrated excellent light transmittance (88 %–90 %) and adjustable haze (45 %–80 %), with a tensile strength approximately 1.5 times that of neat PVA. These results further confirm that the as-prepared CNCs possess excellent material properties and show significant potential for application in various composite materials. Therefore, this work provides a friendly and sustainable strategy for the production of high value-added CNCs from corn straw. • The “enzyme pretreatment/homogenization/enzymolysis” strategy was developed to produce CNCs. • The combination of cellulase and xylanase is highly effective for producing CNCs. • The yield of CNCs was up to 40.3 % through this strategy. • The CNCs/PVA composite film shows high optical and mechanical properties.