Preparation And Characterization Of Novel UV-curable Antimicrobial Polyurethane Coatings

The transmission and infection of pathogens, including microbes and viruses, have resulted in a serious threat for the health. With the increasing public health awareness, researchers have studied on the use of antimicrobial coatings to prevent the growth of harmful bacteria. Normal addition antimicrobial coatings do not meet our need because of releasing of antimicrobial agents into the environment. In the paper, several different antimicrobial polyurethane acrylate oligomers are syntiesized. The antimicrobial films were prepared by oligomers, surface-modified ZnO, reactive diluents and photoinitiator via VU curing method. The details are as follows.1. Starting from the initial materials quaternary ammonium N-Methyldiethanolamine (MDEA-n), isophorone diisocyanate, hexamethylene diisocyanate, and HSH210, the oligomer PUA-MDEA-n was prepared. To improve the dispersion and compatibility, the inorganic antimicrobial agent surface-modified tetrapod zinc oxide whiskers (S-ZnO) was synthesized by reaction between ZnO and KH570. The novelPUA-MDEA-n/S-ZnO composite films were prepared by PUA-MDEA-n oligomers, S-ZnO, reactive diluents and photoinitiator in different percentage via UV curing method. These composite films were characterized by FT-IR, SEM and energy dispersive spectroscopy. The properties of pencil hardness, water uptake, and thermal stabilities for the composite films were measured. The results indicate that all composite films exhibit satisfactory hardness and water uptake. According to thermal gravimetric analyses, all the films have good thermal stability until 260℃. The antimicrobial activities of the prepared composite films were investigated against E. coli and S. aureus. The bacteriostasis rate was up to 99.9% and the Pencil hardness was up to B when the weight percentages of MDEA-14 and S-ZnO additives were 8wt% and 3wt%, respectively.2. The novel organic antimicrobial agent (4-(3-hydroxy-2-(hydroxymethyl)propyl)phenyl)triphenylphosphonium bromide(QPS) was synthesized. Starting from the initial materials (4-(3-hydroxy-2-(hydroxymethyl)propyl)phenyl)triphenylphosphonium bromide, isophorone diisocyanate, hexamethylene diisocyanate, and HSH210, the oligomer PUA-QPS was prepared. The novel PUA-QPS/S-ZnO composite films were prepared by PUA-MDEA-n oligomers, S-ZnO, reactive diluents and photoinitiator in different percentage via UV curing method. These composite films were characterized by FT-IR, SEM and energy dispersive spectroscopy. The properties of pencil hardness, water uptake, and thermal stabilities for the composite films were measured. The results indicate that all composite films exhibit satisfactory hardness and water uptake. According to thermal gravimetric analyses, all the films have good thermal stability until 280℃. The antimicrobial activities of the prepared composite films were investigated against E. coli and S. aureus. The bacteriostasis rate was up to 99.9% and the Pencil hardness was up to HB when the weight percentages of QPS and S-ZnO additives were 3wt% and 3wt%, respectively.3. Starting from the initial materials 2-amino-6-chloropurine derivatives and N,N-Dimethylallylamine, the novel purine quaternary ammonium salts (G-n-DMAA) were prepared. The novel PUA-G-n-DMAA films were prepared by normal oiigomers, G-n-DMAA, reactive diluents and photoinitiator in different percentage via UV curing method. These films were characterized by FT-IR and SEM. The properties of pencil hardness, water uptake, and thermal stabilities for the composite films were measured. The results indicate that all composite films exhibit satisfactory hardness and water uptake. According to thermal gravimetric analyses, all the films have good thermal stability until 260℃. The antimicrobial activities of the prepared composite films were investigated against E. coli and S. aureus. The bacteriostasis rate was only 80.3% and 88.3%, respectively.