Sodium methacrylate is polymerised directly via atom transfer radical polymerisation (ATRP) in aqueous media using a poly(ethylene oxide)-based macro-initiator; the resulting poly(ethylene oxide-block-sodium methacrylate) copolymers were obtained in good yield and have narrow molecular weight distributions as evidenced by aqueous GPC.

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The factors that determine the structure (cis/trans and tacticity) of polymers prepared by ring-opening metathesis polymerization (ROMP) from 2,3-bis(trifluoromethyl)norbornadiene (NBDF6) and several bis(carboalkoxy (norbornadienes using well-defined initiators of the type Mo(NAryl)(CHCMe2-Ph)(OR)2 (Aryl = a substituted aryl group and OR = a variety of alkoxides) have been explored. The main finding is a dependence of cis/trans structure on temperature; at low temperatures (-35 °C) all-cis polymer is formed and at high temperatures (65 °C) up to 90% trans polymers are formed. These results are consistent with formation of cis polymer from syn alkylidene rotamers and trans polymer from anti alkylidene rotamers in circumstances where syn and anti rotamers can interconvert. Several all-cis polymers prepared from achiral initiators that contain various fluorinated alkoxides were found to be biased toward isotacticity. In one case, however, the polymer was biased toward syndiotacticity.

Conjugated light-emitting polymers (LEPs) have real potential to serve as the active layer in a new generation of emissive displays. Emerging as lead candidates for first-generation displays are poly(1,4-phenylene vinylene)s (PPVs) and poly(9,9-dialkylfluorene)s, as well as other polyaromatic materials. The poly(fluorene)s are at present the most commercially developed of these LEP materials for red-green-blue (RGB) applications. The low power consumption of LEP devices in general makes them particularly suited to mobile applications. Combining solutionprocessable emissive polymers with direct-patterning methods such as ink-jet printing will lead to the possibility of low-cost, high-resolution displays. The synthesis and properties of PPVs and poly(9,9-dialkylfluorene)s are briefly reviewed in this article, with a major focus on recent developments. The 2002 MRS Fall Meeting will serve as a key forum for discussion of interdisciplinary leading-edge materials research from around the world. Various meeting formats-oral, poster, round-table, forum and workshop sessions-are offered to maximize participation. www.mrs.org/publications/bulletin

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We have used total internal reflection fluorescence (TIRF) to measure the adsorption kinetics of a newly synthesized fluorescent derivative of a triblock copolymer comprising two poly(ethylene oxide) arms connected by a poly(butylene oxide) segment. The composition is (EO)400 (BO)55 (EO)400, in which EO represents ethylene oxide, BO represents butylene oxide, and one or both of the terminal OH groups of the two (EO)400 arms are labeled with tetramethylrhodamine. The poly(butylene oxide) segment binds to hydrophobic octadecyl glass, used as a substratum. The TIRF signal is shown to be derived almost entirely from surface-adsorbed polymer. This facilitates calculation of adsorption isotherms from 0.1-0.005% bulk polymer solution by means of diffusion kinetics. Information about the effective thickness of the adsorbed polymer, determined by optical interference microscopy, corresponds with what is known about the conformation of similar molecules at interfaces and indicates monolayer adsorption on the glass.