Optical and encapsulation properties of La(OH)3/poly(urethane acrylate) composites

Two lanthanum hydroxide (LH, La(OH)3) materials, i.e., La(OH)3 submicroplates (LHSMPs) and La(OH)3 nanoparticles (LHNPs), were synthesized hydrothermally, and their optical and encapsulation properties were investigated. The surfaces of the LHSMPs and the LHNPs were modified with a coupling agent: [3-(methacryloyloxy)propyl] trimethoxysilane (MPS). To prepare transparent encapsulation composite materials, both types of surface-modified particles were dispersed in a poly(urethane acrylate) (PUA) adhesive polymer binder. The composite film with surface-modified LHNP-PUA exhibited better optical properties (higher transmittance and lower haze) than that with surface-modified LHSMP-PUA owing to smaller particle size. However, the latter was observed to be more advantageous for preventing the permeation of water molecules owing to the larger particle size. [Display omitted] •La(OH)3 submicroplates (LHSMPs) and La(OH)3 nanoparticles (LHNPs) are synthesized by a hydrothermal method.•The surfaces of particles are modified by MPS.•LHNPs exhibited higher transmittance and lower haze than LHSMPs owing to the smaller particle size.•LHSMPs exhibited better encapsulation properties against water permeation than LHNPs owing to the larger particle size.