Influence of hardeners on the performance properties of naturally dry polyorganosiloxane coatings

• Main Authors: Suchkov, V. S., Ziganshina, M. R., Stepin, S. N., Mendelson, V. A.
• Format: Conference Proceeding
• Language: English
• Subjects: Additives; Aminopropyltriethoxysilane; Chemical synthesis; Coatings; Crosslinking; Fragility; Hardeners; Hydroxyl groups; Low molecular weights; Mechanical properties; Moisture effects; Petroleum products; Polyester resins; Thermal stability
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0143604

High thermal stability of naturally dried polyorganosiloxane coatings is accompanied by fragility, limited resistance to petroleum products’ and synthetic oils’ attack and, as a rule, insufficiently high adhesive and physical and mechanical characteristics. This is due to the low molecular weight of the film-forming oligomers used in coatings’ preparation. The end silanol groups of the latter as a rule are butanolized. Their chemical activation efficiency level due to hydrolysis with air moisture does not allow the formation of crosslinked structures without heating. In this work, the reaction of ɣ-aminopropyltriethoxysilane with linear and branched polyesters containing epoxy and hydroxyl groups the hardeners-modifiers are synthesized. Their addition makes it possible to carry out the chemical structuring of polyorganosiloxane coatings in natural conditions without heat supply. This confirmed the positive effect of the additives on the complex of polymethylphenylsiloxane coatings service properties. The results obtained allowed us to conclude that the branching of molecules, the content of ethoxysilane groups in the hardener’s composition and the inter-node distances of the crosslinked structure have a complex effect on the properties of the coatings being formed. Obviously, a further way to optimize the complex of the coatings’ service properties is chemical structuring using combinations of synthesized hardeners.