The combined effect of hydrophobic poly(dimethylsiloxane) chains and polyhedral oligomeric silsesquioxanes in protective coatings for AA 2024 alloy was investigated using standard electrochemical techniques. The coatings were subjected to ex situ and in situ vibrational spectroscopies to follow the changes in the bands of protective coatings during forced anodic polarisation. The ex situ IR reflection–absorption measurements were performed under near-grazing conditions (80°), yielding changes mainly in the C–H stretching region. Confocal Raman measurements were made under in situ conditions in a specially designed spectroelectrochemical cell. The results that could be obtained with both vibrational techniques are presented.
COBISS.SI-ID: 5491226
Fluoropolymer conformal coatings were applied to electronic boards (EBs) and cured at room temperature or 80°C. The coatings were first deposited on model substrate, i.e. aluminium alloy AA 2024 and tested for their anticorrosion properties with a potentiodynamic polarisation technique. The cathodic current densities ranged from 10−9 to 10−10 A/cm2, approaching the lower current limit after the addition of TiO2 nanoparticles into the formulation. Application of fluoropolymer-based formulation was performed via spray-coating deposition. Examination of the coverage of EBs under UV light, which is commonly used in industry, revealed that some components might not be entirely covered. In the search for other possible analytical tools of coverage with protective coatings, optical microscopy and confocal Raman spectroscopy were investigated.
COBISS.SI-ID: 5544986
In situ rheological study of sol-gel process was performed with 3-glycidoxypropyl-terminated polydimethyl-siloxane based sols. A continuous following of rheological properties enabled a precise insight in gelation process resulting in exact prediction of gelation time, structural changes and final rheological properties of formed gel. Moreover, as polyhedral oligomeric silsesquioxanes (POSS) are successfully used compounds for improvement of various polymer properties, the influence of POSS on rheological properties, combined with the impact on thermal behaviour and electrochemical properties was studied.
COBISS.SI-ID: 37562117