Influence of organic acid modification on enhancing the grinding efficiency and particle size distribution

In this study, the widely used grinding aids (GAs) TIPA, DEIPA, and DEG were chemically modified via esterification with organic acids of varying hydrocarbon chain lengths to improve grinding efficiency and cement performance. A total of 25 Portland cement samples were produced using commercial and modified GAs at 0.05% and 0.1% dosages. The effects of GA modification on adsorption behavior, grinding efficiency, particle size distribution (PSD), zeta potential, and molecular polarization characteristics were systematically investigated. The results demonstrated a clear structure-performance relationship between the molecular structure of modified GAs and their grinding behavior. Hexanoic acid modification of TIPA and DEIPA increased molecular polarizability and adsorption capacity, resulting in a more uniform PSD and up to 7-10% higher grinding efficiency compared to the corresponding commercial GAs. In contrast, DEG modified with propanoic acid exhibited the best overall performance among DEG-based formulations, providing improved particle dispersion and enhanced grinding characteristics. The findings further revealed that the ester/hydroxyl group balance and hydrocarbon chain length strongly influenced molecular dipole moment and polar interactions with cement particles. Overall, the proposed polarization-based mechanism successfully explains the enhanced adsorption, dispersion, and grinding performance of the modified GAs.