Poly(methyl methacrylate)-silica-calcium phosphate coatings for the protection of Ti6Al4V alloy

Autor(es)

Uvida, Mayara Carla ; Pulcinelli, Sandra Helena ; Santilli, Celso Valentim ; Hammer, Peter

• Tipo de documento: Artigo Científico
• Fonte: Journal of Sol-Gel Science and Technology; v. N/A, p. 12-pg., 2023-04-18.

Resumo

Poly(methyl methacrylate) (PMMA)-silica coatings modified with calcium phosphates (CaPs) in the form of hydroxyapatite (HA) and beta-tricalcium phosphate (beta-TCP) have been developed to improve the corrosion resistance and bioactivity of Ti6Al4V titanium alloys, applied in medical and dental implants. PMMA-silica hybrids containing 1000 ppm HA or beta-TCP were prepared by combining the sol-gel reactions of tetraethylorthosilicate (TEOS) with the radical polymerization of methyl methacrylate (MMA) and 3-methacryloxypropyl trimethoxysilane (MPTS), used as molecular coupling agent. Bi-layer coatings about 15 mu m thick, deposited by immersion on Ti6Al4V, are homogeneous, defect-free, and exhibit strong adhesion to the substrate (>14 MPa). The addition of HA and beta-TCP led to a slight increase in thermal stability, without affecting the structural integrity of the highly crosslinked PMMA-silica matrix. The greater hydrophilicity and surface roughness of coatings containing HA and beta-TCP are associated with the size and chemical composition of CaPs, necessary for effective osteointegration. The modified coatings showed high anti-corrosion efficiency with low-frequency impedance modulus values of up to 73 G Omega cm(2), remaining stable after 150 days of exposure to simulated body fluid (SBF) solution. [GRAPHICS] . (AU)

• Processo FAPESP: 19/13871-6 - Desenvolvimento de nanocompósitos multifuncionais
• Beneficiário: Peter Hammer
• Modalidade de apoio: Auxílio à Pesquisa - Regular