Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Fabrication of siloxane protective coatings with biocidal properties based on MT resins and functional polydimethylsiloxanes.

ABSTRACT
In this study, MT resins (consisting of mono- and trifunctional alkoxysilanes) containing varying amounts of perfluoroalkyl and guanidinoalkyl substituents were synthesized via hydrolytic polycondensation in an active medium. Based on these resins, silicone-based protective coatings were prepared using PDMS modified with 3-aminopropyltriethoxysilane as a cross-linking agent. This approach was used for the first time to obtain bacteriostatic coatings and has a number of advantages: low cost, scalability, and the ability to vary the functional components of the compositions over a wide range. Optimization of the coating application process demonstrated that applying the coatings from solution resulted in an 8-fold improvement in surface roughness. The resulting protective coatings were evaluated for their bacteriostatic activity against Gram-negative (E. coli ATCC 25922, P. aeruginosa ATCC 27853, P. aeruginosa 58, P. aeruginosa 60, K. pneumoniae ATCC 700603) and Gram-positive (S. aureus ATCC 43300, S. aureus ATCC 700699, E. faecalis ATCC 29212, and the clinical strain E. faecium 3576) bacterial strains at a cell concentration of 106–107 CFU/mL. Comparing perfluoroalkyl- and guanidine-containing coatings, it was shown that for coatings of this type, surface roughness plays a significant role in bacteriostatic impact. Further work in this direction will make it possible to obtain effective bacteriostatic coatings with good physical and mechanical properties, which is important for increasing durability and wear resistance.