Optical and dielectric studies of PMMA: precursors of BNT hybrid films

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2019-05, Vol.125 (5), p.1-9, Article 367
• Main Authors: Escamilla-Díaz, T., Serralta-Macías, J. J., García-Zaldivar, O., Cruz-Valeriano, E., Ramírez-Bon, R., Yañez Limón, J. M.
• Format: Article
• Language: English
• Subjects: Applied physics; Atomic force microscopy; Bismuth titanate; Characterization and Evaluation of Materials; Chemical composition; Condensed Matter Physics; Coupling agents; Density currents; Dielectric properties; Electric potential; Electrical measurement; Fourier transforms; Functional groups; Machines; Manufacturing; Materials science; Morphology; Nanotechnology; Optical and Electronic Materials; Optical properties; Organic chemistry; Physics; Physics and Astronomy; Polymethyl methacrylate; Precursors; Processes; Refractivity; Silicon dioxide; Sol-gel processes; Stability analysis; Surfaces and Interfaces; Thermal stability; Thermogravimetric analysis; Thin Films; Titanium dioxide
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-019-2658-x

In this study, polymethyl methacrylate (PMMA)-based organic–inorganic hybrid films were deposited by the sol–gel technique by mixing the methyl methacrylate (MMA) organic precursor solution with an inorganic precursor solution of bismuth sodium titanate (Bi 0.5 Na 0.5 TiO 3 or commonly known as BNT). 3-(trimethoxysilyl) propyl methacrylate (TMSPM) was used as coupling agent to improve the compatibility between the phases. The chemical composition and thermal stability were monitored by FTIR spectroscopy and thermogravimetric analysis. The high thermal stability observed together with the appearance of functional groups related to Si–O–metal interactions confirms the formation of a hybrid organic–inorganic material. A study of the optical properties by UV–Vis was also performed, where the refractive index between 2.1 and 2.6 was obtained, corroborating a good coupling between the organic and inorganic phases in the hybrid films. Atomic force microscopy measurements were also made to determine the surface morphology and roughness of the hybrid films and bear out their homogeneity. Finally, electrical measurements were performed by capacitance–voltage ( C – V ) and current–voltage ( I – V ), to obtain the dielectric permittivity constant with values from 15.5 to 18.5 and density current from 1 × 10 −5 to 1 × 10 −6  A cm −2 . In comparison with other PMMA-based hybrid materials such as those containing the precursors TiO 2 or SiO 2 , the PMMA–BNT hybrid material shows an improvement in its optical and dielectric properties.