ABSTRACTAny microorganisms killing molecules have some cytotoxicity more or less. The effective way of reducing cytotoxicity mainly included two approaches: One was reducing the concentration of antiseptic, while this would lead to the decreased antimicrobial efficiency; the other way was choosing suitable antiseptics and then combining of them, which can balance the disinfection and cytotoxicity. In this paper, hydroxypropyltrimethyl ammonium chloride chitosan (HACC), a cationic natural macromolecular, as the first antiseptic, incorporated with polyhexamethylene biguanide (PHMB), a smaller molecular weight cationic antiseptic polymer, as the second antiseptic, their disinfection effect and cell cytotoxicity in borate buffer solution were investigated at fairly low contents. When HACC/PHMB weight ratios were 100/1 and 150/1, the disinfection solutions produced >1-log reductions against C. albicans and >3-log reductions against S. aureus and P. aeruginosa. HACC/PHMB disinfection solution at weight ratio of...

ABSTRACTCrown ether complexes of sodium and potassium 2-(benzotriazol-2-yl)phenolates were synthesized and characterized. In the presence of BnOH these complexes are highly active catalysts for the...

Polyimide‐silica hybrid materials have been prepared through the sol‐gel process by mixing various proportions of tetraethoxysilane (TEOS) with polyamic acids (PAAs). Two types of PPAs were employed. The first was obtained by reacting an equimolar mixture of oxydianiline (ODA) and pyromellitic dianhydride (PMDA) in dimethylactamide (DMAc) as solvent. The second was prepared using a mixture of ODA and 2,2‐Bis(3‐amino‐4‐hydroxyphenyl)hexafluoropropane (6F‐OHDA) in molar ratio 9:1, respectively and reacting with a stoichiometric amount of PMDA in DMAc. Polyamic acids were converted to polyimides and a sol‐gel reaction proceeded simultaneously by heating the hybrid films to 300°C. The hydroxyl groups from 6F‐OHDA allows the secondary bonding between the polyimide and growing silica phase and thus retard the gross phase separation. Only the 10 mol% addition of 6F‐OHDA in the polyimide chain resulted in a drastically different microstructure for the resulting hybrids. SEM, stress‐strain analysis, temperature va...