Nasim Nahavandizadeh

Chemical modification of biomass, including cellulose, is often carried out in multiphase reactions, where the solid biomass interacts with reactants in mixed solid, liquid, and gas phases. Ideally, chemical reagents distribute uniformly within the cellulose matrix, producing a homogeneous product. However, batch-to-batch variations can still occur despite achieving the same degree of modification, affecting mechanical strength, durability, and overall performance. To study how modifications spread within a biomass particle, we use Dynamic Nuclear Polarization-enhanced Nuclear Magnetic Resonance (DNP-NMR). This technique boosts signal strength by transferring polarization from electron spins to nearby nuclear spins using microwaves. We also use spin diffusion, which helps spread this enhanced signal throughout the sample, allowing us to see how evenly the modification is distributed. This method provides valuable insights into batch variations and helps improve the consistency of chemically modified cellulose.