Ref.: MpoCo35-002
Apresentador: Paulo Alexandre Silveira da Silva
Autores (Instituição): Silveira da Silva, P.A.(Federal University of Paraná); Pirola, A.d.(Federal University of Paraná); Eiras, D.(Federal University of Paraná); Marino, C.E.(Federal University of Paraná);
Resumo:
According to the Association for Materials Protection and Performance, corrosion costs reach up to 3.4% of the global GDP, and approximately 35% of this damage could be prevented with corrosion protection methods. However, current protection methods have shortcomings, such as epoxy resin, despite being widely used, leaches compromising film integrity and protection capacity. Faced with this limitation, the development of new technologies is necessary, and polydopamine appears to be a promising approach. Polydopamine (PDA) is a bioinspired polymer based on proteins secreted by the mussel byssus. It is a powerful tool for functionalizing chemically inert surfaces and shows great adhesion potential for a variety of materials. The main objective of this study is to evaluate and develop a methodology for the synthesis and recovery of polydopamine for application in coatings, acting as a barrier for corrosion protection. The polymer synthesis method was performed by dopamine autoxidation in an alkaline environment, as described by Wu et al [1]. PDA powder was obtained by adapting the protocol through vacuum filtration with a membrane composed of 15% polysulfone and 10% polyetherimide, followed by drying in an oven at 60°C. From a 200 ml reaction containing 0.4 g of dopamine, 0.135 g of PDA powder was obtained, this gives a total conversion of 33.7% of dopamine to PDA. In this study, techniques such as Energy Dispersive X-ray Spectroscopy were used in conjunction with scanning electron microscopy, allowing morphological and semi-quantitative analysis of the chemical elements present in the sample, which exhibited clustered spherical structures, with a high content of carbon, oxygen, and nitrogen. Additionally, Fourier Transform Infrared Spectroscopy and Raman Spectroscopy were also used to confirm PDA synthesis by detecting functional groups, as evidenced by the absorption band around 3250 - 3350 cm-1 corresponding to the vibrations of -NH and catechol -OH groups in FTIR. Furthermore, characteristic PDA peaks at 1353 cm-1 and 1583 cm-1 were detected in the Raman spectra, indicating the presence of pyrrole and indole rings. Although the synthesis results have shown an apparently low yield, it is important to emphasize that the absence of previous literature data limits to directly assess the method's yield. Therefore, it should be considered within the context of the originality and scientific advancement that this study represents, particularly given the demonstration of the method's effectiveness through the successful synthesis of polydopamine, enabling the following of this research into green coatings for protection against corrosion.
Acknowledgments:
To UFPR, PIPE, CAPES, and the advisor professors.
References:
[1] WU, M. et al. Adjustable synthesis of polydopamine nanospheres and their nucleation and growth. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2020