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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Barrier properties of high performance PMMA-silica anticorrosion coatings

Texto completo
Autor(es):
Trentin, Andressa [1] ; Gasparini, Andressa de L. [1] ; Faria, Flavio A. [1] ; Harb, V, Samarah ; dos Santos, Fabio C. [2] ; Pulcinelli, Sandra H. [2] ; Santilli, V, Celso ; Hammer, Peter [3]
Número total de Autores: 8
Afiliação do(s) autor(es):
[1] Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP - Brazil
[2] Harb, Samarah, V, Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP - Brazil
[3] Santilli, Celso, V, Harb, Samarah, V, Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP - Brazil
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: Progress in Organic Coatings; v. 138, JAN 2020.
Citações Web of Science: 4
Resumo

This work reports a detailed investigation of the structural and electrochemical barrier properties of PMMA-silica coatings. Hybrid nanocomposites were prepared by combining the sol-gel method with the polymerization of methyl methacrylate (MMA), using the thermal initiator benzoyl peroxide (BPO), followed by the hydrolytic condensation of tetraethoxysilane (TEOS) and 3-(trimethoxysilyl)propyl methacrylate. Raman spectroscopy and thermal analysis showed that the fine-tuning of the BPO amount, a critical synthesis parameter, improved the polymerization efficiency of MMA, leading to a highly cross-linked hybrid structure. The homogeneous coatings prepared under optimized synthesis conditions presented elevated thermal stability due to improved polymerization of the organic phase. Electrochemical impedance spectroscopy (EIS) showed a quasi-ideal capacitive impedance response in 3.5% NaCl solution, with low frequency impedance modulus of up to 10 G Omega cm(2), which remained essentially unchanged during 19 months of immersion. This notable barrier property was modeled by fitting the EIS curves assuming slowly expanding electrolyte uptake, using the two-layer Young approach, and by comparison with the standard equivalent electrical circuit (EEC/CPE) model. The Young model provided valuable information on the time evolution of physical parameters including the thickness of the uptake zone, the conductivity depth-profile and the dielectric constant, among others, evidencing the high performance of the coatings. (AU)

Processo FAPESP: 15/09342-7 - Desenvolvimento de híbridos PMMA-(TiO2, ZrO2 e CeO2) multifuncionais
Beneficiário:Samarah Vargas Harb
Linha de fomento: Bolsas no Brasil - Doutorado
Processo FAPESP: 15/11907-2 - Estrutura e propriedades eletroquímicas de revestimentos híbridos PMMA-silica modificados com ions cério e lítio.
Beneficiário:Andressa Trentin
Linha de fomento: Bolsas no Brasil - Doutorado
Processo FAPESP: 14/12182-9 - Análise mecânica por nanoindentação, microscratch e testes de desgaste de revestimentos anticorrosivos híbridos siloxano-PMMA reforçados por nanotubos de carbono e grafeno
Beneficiário:Samarah Vargas Harb
Linha de fomento: Bolsas no Exterior - Estágio de Pesquisa - Mestrado