Composite polymer particles containing bismuth vanadate particles for self-cleaning fabrics

The aim of this research was to prepare composite polymer particles containing bismuth vanadate (BiVO4) particles through microsuspension iodine transfer polymerization ( ms ITP) for fabric coating as a self-cleaning fabric. To reduce the aggregation of pristine BiVO4 particles during the fabric coating process, composite polymer particles containing the visible-light-driven photocatalyst as BiVO4 particles in self-cleaning fabric applications were investigated in the first time. First, BiVO4 particles were prepared via an aqueous chelating method where the stable precursor solutions of Bi3+ and V5+ with ethylenediaminetetraacetic acid ligand were obtained. After calcination at 500 °C, the BiVO4 particles were obtained. To disperse them well in an oil (monomer) phase in ms ITP, the BiVO4 surface was modified by oleic acid as o-BiVO4 to present a hydrophobic surface. The encapsulation efficiency of the o-BiVO4 (≥60%) in composite poly(methylmethacrylate-divinylbenzene) (P[MMA-DVB]/o-BIVO) particles was significantly higher than that (≈10%) of the pristine BiVO4 particles. Using polyethylene glycol 30 dipolyhydroxystearate (DPHS) as a porogen, porous P(MMA-DVB)/o-BiVO4 particles still maintaining their spherical shape were obtained with an 8% particle of DPHS. Furthermore, increasing the hydrophilic polymer shell by adding 2-hydroxyethyl methacrylate (HEMA) in the oil phase of ms ITP, the P(MMA-DVB-HEMA)/o-BiVO4 particles showed a much higher methylene blue (MB) degradation rate under visible light for 1 h (24 mg MB/g BiVO4 or 96% MB degradation) than that (13 mg MB/g BiVO4 or 52% MB degradation) of the pristine BiVO4. Moreover, the fabric coated with porous P(MMA-DVB-HEMA)/o-BiVO4 particles showed a satisfactory self-cleaning property.