PU (Polyurethane) Aqueous Dispersion as Battery Electrode Binder, 20 g/bottle, CBEBPUAD

Aqueous polyurethane dispersions (PUDs) are emerging as highly effective, environmentally friendly alternative binders to traditional PVDF (polyvinylidene fluoride) for battery electrodes. They offer unique elastomeric properties that are particularly beneficial for next-generation chemistries undergoing large volume changes.

PUDs are binary systems consisting of polyurethane particles dispersed in water. Because polyurethane is naturally hydrophobic, specific chemical modifications are required to make it dispersible in water without settling: (1) Internal Emulsifiers: During synthesis, hydrophilic monomers—most commonly DMPA (dimethylolpropionic acid) for anionic dispersions or MDEA (N-methyldiethanolamine) for cationic dispersions—are incorporated into the polyurethane backbone. (2) Neutralization: The carboxylic acid groups from DMPA are neutralized with a base (like triethylamine, TEA), creating ionic centers (-COO-HN+Et3) along the polymer chain. (3) Dispersion: When introduced to water under high shear, these ionic centers orient outward toward the aqueous phase, creating electrostatic repulsion that keeps the PU particles stably suspended without the need for external surfactants (which could degrade electrochemical performance).

Compared to rigid binders like PVDF or standard CMC/SBR (carboxymethyl cellulose / styrene-butadiene rubber) systems, PUDs offer distinct mechanical and processing advantages: (1) High Elasticity and Toughness: Polyurethane possesses a segmented structure consisting of alternating hard segments (diisocyanates and chain extenders providing mechanical strength) and soft segments (polyols providing flexibility). This gives PUD binders excellent elongation-at-break, allowing the electrode matrix to accommodate severe volume expansion and contraction—such as in silicon-dominant anodes or high-capacity conversion/alloying materials—without pulverization or delamination. (2) Excellent Adhesion: The abundant urethane (-NH-COO-), urea (-NH-CO-NH-), and ionic groups form strong hydrogen and electrostatic bonds with both the current collector (copper/aluminum) and the active material particles. (3) Tunable Chemistry: By varying the polyol type (ether, ester, carbonate, or butadiene-based) or the hard-to-soft segment ratio, the binder's mechanical strength, swelling behavior in organic electrolytes, and electrochemical window can be precisely engineered.

Part Number	CBEBPUAD (C-BEB-PUAD)
CAS	9009-54-5
Chemical Formula/Structure
Appearance	Milky White Slurry
Solid Content	10.5 %
Package Size	20 g/bottle

Notes: Please try to store the PU aqueous dispersion in a dry place.

References: 

1. N. Loeffler, et al. Polyurethane Binder for Aqueous Processing of Li-Ion Battery Electrodes, J. Electrochem. Soc., 2015, 162, A2692.
2. X. Liu, et al. Se–Se Bonds Involved Polyurethane-Based Binders for Enhanced Redox Kinetics in Lithium-Ion Batteries, ACS Appl. Polym. Mater. 2025, 7, 6, 4019–4028.