Studie vlivu poměru složek polyuretanových nátěrových systémů na kvalitu povlaku

Abstract

The presented master thesis experimentally evaluates the influence of the stoichiometric ratio of components in two-component polyurethane systems on the overall quality and protective function of the resulting coatings. The research compares two distinct commercial coating systems – PPG SigmaFast 210 HS and CIN C-Thane S350, where the volume of the isocyanate hardener was intentionally modified in a range from -60 % to +60 % compared to the manufacturer's recommendation. The integrity of the polymer network was investigated using destructive mechanical testing, adhesion tests, chemical resistance evaluations, and FTIR-ATR spectroscopy. The acquired results demonstrate that a hardener deficit induces a catastrophic loss of mechanical toughness and a failure of barrier properties due to unreacted polyols, whereas its excess maximizes chemical resistance at the cost of increased material fragility. The thesis establishes the necessity of precise technological discipline during the mixing of systems intended for highly aggressive corrosive environments (C4, C5).