Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Interfacial engineering with RAFT-polymerized bismuth particles in PVA fibers enables highly filled, lead-free fabrics with 41.66% γ-rays shielding and superior air/moisture permeability, advancing flexible, comfortable radiation protection PPE.

ABSTRACT
Radiation protection safety and wear comfort of personal protective equipment (PPE) is of great significance to the harmonization of the flourishing nuclear technology. However, toxic lead and poor air permeability in common rubber-based composites are incompatible with present needs. Here, interfacial engineering is proposed to fabricate highly-filled polyvinyl alcohol (PVA) fibers with environment-friendly bismuth (Bi) particles and its fabrics for enhanced γ-rays shielding and air permeability. Reversible addition-fragmentation chain transfer (RAFT) polymerization is applied to graft poly maleic acid (PMA) chains on Bi particles, enabling the increase in the interfacial area between the fillers and PVA matrixes for interfacial reinforcement. As the filling amount reaches 30%, tensile strength of pure Bi/PVA fiber is recorded at 1.58 cN/dtex, Bi@PMA/PVA fiber is measured at 4.19 cN/dtex. This strategy enables the fabrication of highly-filled PVA fibers as high as 60 wt% loading of the fillers for better radiation shielding. The resultant multilayer fabrics exhibit 41.66% of γ-rays shielding efficiency for 105 keV, air permeability (104.88 mm/s), and moisture vapor transmission (2945.41 g/m2 24 h). These characteristics demonstrate a proper balance between air permeability and radiation shielding. This work holds huge promise for the advancement of next-generation PPEs with radiation protection safety and wear comfort.