Antireflection coatings formed from polyelectrolyte multilayers on PMMA substrate

Abstract

An antireflection coating on a polymeric methyl methacrylate substrate is fabricated by poly(allylamine hydrochloride)/poly(acrylic acid) (PAH/PAA) layer by layer deposition method. The authors investigated the effects of acidic treatments of pH 1·8 H₂O, pH 2·4 0·05M MgCl₂ (NaCl) and different concentrations of PAA on transmissions of the film and resistance to phase separation induced by water and NaCl solution. Different acidic treatments lead to distinct mechanisms of forming nanopores. The optimum of average transmission of the film, 96·86%, at 350–800 nm was obtained using the MgCl₂ acidic treatment. The polarised water molecules, Na⁺ and Cl⁻, attract polyanions and polycations of PAH/PAA film. Therefore, the resistance to phase separation induced by water and NaCl solution is poor.