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Controlled free‐radical copolymerization of styrene (S) and butyl acrylate (BA) was achieved by using a second‐generation nitroxide, N‐tert‐butyl‐N‐[1‐diethylphosphono‐(2,2‐dimethylpropyl)] nitroxide (DEPN), and 2,2‐azobisisobutyronitrile (AIBN) at 120 °C. The time‐conversion first‐order plot was linear, and the number‐average molecular weight increased in direct proportion to the ratio of monomer conversion to the initial concentration, providing copolymers with low polydispersity. The monomer reactivity ratios obtained were rS = 0.74 and rBA = 0.29, respectively. To analyze the convenience of applying the Mayo–Lewis terminal model, the cumulative copolymer composition against conversion and the individual conversion of each monomer as a function of copolymerization time were studied. The theoretical values of the propagating radical concentration ratio were also examined to investigate the copolymerization rate behavior. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4168–4176, 2004

The development of inherent antimicrobial polymeric fibers can contribute to overcoming the increasing problem of infectious diseases and multiresistant microorganisms. Here, we propose the preparation of poly(lactic acid) (PLA) based electrospun fibers blended with poly[2-(4-methylthiazol-5-yl)ethyl methacrylate] (PMTA), which quaternized have proven broad spectrum antimicrobial activity either in solution or solid state. We have demonstrated that quaternized PLA/PMTA fiber mats have a remarkable antibacterial activity against S. aureus. As determined by scanning electron microscopy and Raman spectroscopy, quaternized PMTA segregates toward the outmost surface of PLA/PMTA fiber leaving the thiazolium group widely available onto the fiber surfaces, facilitating the bacteria killing by contact mode.

Herein, contact active antimicrobial films are prepared by simply blending cationic amphiphilic block copolymers with commercial polystyrene (PS). The copolymers are prepared by combining atom transfer radical polymerization and "click chemistry." A variety of copolymers are synthesized, and composed of a PS segment and an antimicrobial block bearing flexible side chain with thiazole and triazole groups, 4-(1-(2-(4-methylthiazol-5-yl)ethyl)-1H-1,2,3-triazol-4-yl) butyl methacrylate (TTBM). The length of the TTBM block is varied as well as the alkylating agent. Different films are prepared from N,N-dimethylformamide solution, containing variable PS-b-PTTBM/PS ratio: from 0 to 100 wt%. Remarkably, the blend films, especially those with 30 and 50 wt% of copolymers, exhibit excellent antimicrobial activities against Gram-positive, Gram-negative bacteria and fungi, even higher than films prepared exclusively from the cationic copolymers. Blends composed of 50 wt% of the copolymers present a more than 99.999% killing efficiency against the studied microorganisms. The better activity found in blends can be due to the higher roughness, which increases the surface area and consequently the contact with the microorganisms. These results demonstrate that the use of blends implies a reduction of the content of antimicrobial agent and also enhances the antimicrobial activity, providing new insights for the better designing of antimicrobial coatings.

Two chemical structural isomers, 2-hydroxyethyl methacrylate and ethyl ␣-hydroxymethyl acrylate, were copolymerized with dimethyl amino ethyl methacrylate in bulk at 50°C with 1.0 ϫ 10 Ϫ2 mol/L 2,2Ј-azobisisobutyronitrile as an initiator. Experiments showed differences in the values of the monomer reactivity ratios due to electronic or steric contributions to the cross-propagation reaction. The homopolymer glass-transition temperature (T g ), along with the intramolecular and intermolecular structure and Johnston's equation, enabled a description of the experimental variations of the copolymer T g .

Herein, we report, for the first time, the synthesis of clickable polymers derived from biobased itaconic acid, which was then, employed for the preparation via click chemistry of novel cationic...

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