Antibacterial coatings are becoming increasingly attractive for application in the field of biomaterials. In this framework, we developed polymer coating zirconia with antibacterial activity using the "grafting from" methodology. First, 1-(4-vinylbenzyl)-3-butylimidazolium chloride monomer was synthesized.
View Article and Find Full Text PDFA simple and rapid access to fluorinated dithioesters was developed by a one-pot sequence corresponding to a Grignard reaction-Mitsunobu type substitution. These activated dithioesters have shown excellent reactivity in an aminolysis reaction from simple or more complex primary amines such as cinchona alkaloids. A stoichiometric amount of amine was sufficient to prepare various thioamides, including a 4-styrenylthioamide cinchonidine monomer, under environmentally friendly conditions, at room temperature, and in a very short time.
View Article and Find Full Text PDFSurfactants are crystallizing a certain focus for consumer interest, and their market is still expected to grow by 4 to 5% each year. Most of the time these surfactants are of petroleum origin and are not often biodegradable. Cashew Nut Shell Liquid (CNSL) is a promising non-edible renewable resource, directly extracted from the shell of the cashew nut.
View Article and Find Full Text PDFCalixarenes are cyclic oligomers obtained by condensation of suitable p-functionalised phenols with formaldehyde, usually allowing for the synthesis of the well known small calixarenes (including up to eight phenolic subunits). We report here the discovery of much larger members of this family, exhibiting sizes up to 90 phenolic subunits: the giant calixarenes. These macrocycles are obtained according to simple, easily scalable processes, in yields up to 65%.
View Article and Find Full Text PDFChitosan with its surface-properties and biodegradability is a promising biomaterial for green packaging applications. Till now, this application is still limited due to chitosan high sensitivity to water. Some existing studies deal with the incorporation of hydrophobic additives to enhance water-proof performances of chitosan films.
View Article and Find Full Text PDFMicrobial burden associated with medical devices poses serious health challenges and is accountable for an increased number of deaths leading to enormous medical costs. Catheter-associated urinary tract infections are the most common hospital-acquired infections with enhanced patient morbidity. Quite often, catheter-associated bacteriuria produces apparent adverse outcomes such as urosepsis and even death.
View Article and Find Full Text PDFPoly(ethylene terephthalate) (PET) substrates were modified by means of surface-initiated supplemental activator and reducing agent atom transfer radical polymerization (SI-SARA-ATRP) of 4-vinylpyridine (4VP). Substrates were pretreated in order to graft chloromethylbenzene (CMB) units capable of initiating the radical polymerization reaction of 4VP units. Surface characterization techniques, including Water Contact Angle (WCA), Attenuated Total Reflection (ATR), X-ray photoelectron spectroscopy (XPS), Atomic Force Microscopy (AFM) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) showed a successful grafting of a stable, smooth and homogenous layer of p4VP.
View Article and Find Full Text PDFThis study deals with the grafting of carbohydrate monomers on poly(ethylene terephthalate) fibers by double argon plasma treatment. Two monomers were used: allyl alpha-D-galactopyranoside and 2-methacryloxyethyl glucoside. The quantity of grafted carbohydrates was determined by phenol/sulfuric acid colorimetric titration.
View Article and Find Full Text PDFThe two-dimensional self-assembly at the air/water (A/W) interface of two dendrimer-like copolymers based on polystyrene and poly(tert-butyl acrylate) (PS-b-PtBA) or poly(acrylic acid) (PS-b-PAA) was investigated through surface pressure measurements (isotherms, isochores, and compression-expansion hysteresis experiments) and atomic force microscopy (AFM) imaging. The two dendrimer-like block copolymers have an 8-arm PS core (Mn = 10 000 g/mol, approximately 12 styrene repeat units per arm) with a 16-arm PtBA (Mn = 230 000 g/mol, approximately 112 tert-butyl acrylate repeat units per arm) or PAA (Mn = 129 000 g/mol, approximately 112 acrylic acid repeat units per arm) corona. The PS-b-PtBA sample forms stable Langmuir monolayers and aggregates into circular surface micelles up to a plateau observed in the corresponding isotherm around 24 mN/m.
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