A comprehensive characterization of the controlled radical copolymerization of styrene and n-butyl acrylate comonomers is obtained by using a recently introduced method termed automatic continuous online monitoring of polymerization reactions (ACOMP). By simultaneously monitoring and combining signals from a continuously diluted reactor stream, light scattering, viscosity, differential refractive index, and UV absorption were used, in a model-independent fashion, to follow the weightaverage molecular weight M w, weight-average intrinsic viscosity [η]w, the concentrations of each comonomer, and hence also the evolution of the average instantaneous and cumulative compositions along the chains as comonomers were consumed. The "composition profile" along the chain will largely influence the copolymer properties, and it is suggested that gradient copolymers might also be termed "profiled copolymers", which then includes di-and multiblock polymers. Invoking the Mayo-Lewis model allowed sequence length averages and reactivity ratios to be computed. It is believed that the use of ACOMP with gradient copolymerization will lead to a better understanding of underlying kinetics and mechanisms and eventually lead to the ability to control the composition profile formation during the polymerization reaction.

The grafting of "living" polystyrene-block-poly(1,3-cyclohexadiene)-block-styryllithium and poly(1,3-cylclohexadiene)-block-polystyryllithium onto C 60 yielded, respectively, 6-star-fullerene[styreneblock-poly(1,3-cyclohexadiene)-block-polystyrene] and 6-star-fullerene[polystyrene-block-poly(1,3-cyclohexadiene)]. Selective dehydrogenation of these macromolecules yielded, respectively, 6-star-fullerene-[styrene-block-poly(1,4-phenylene)-block-polystyrene], C60(st-PPP-PS)6, and 6-star-fullerene [polystyreneblock-poly(1,4-phenylene)], C60(PS-PPP)6. 6-star-Fullerene[poly(1,4-phenylene)-block-polystyrene] could not be synthesized via this route as fullerene-poly(1,3-cyclohexadiene) bonds were found to form without control and to degrade during aromatization. Star copolymers containing conjugated PPP were characterized by size exclusion chromatography, UV, and fluorescence spectroscopy. Fluorescence quantum yields of C 60(st-PPP-PS)6 and C60(PS-PPP)6 in THF were compared and discussed in light of characterizations of PPP-PS-PPP in comparable conditions without or mixed with C60(PS)6.

This mini-review focuses on two different miniaturizing approaches: the first one describes the generation and use of droplets flowing within a millifluidic tool as individual batch microreactors. The second one reports the use of high pressure microflows in chemistry. Millifluidics is an inexpensive, versatile and easy to use approach which is upscaled from microfluidics. It enables one to produce hierarchically organized multiple emulsions or particles with a good control over sizes and shapes, as well as to provide a convenient data acquisition platform dedicated to slow or rather fast chemical reactions, i.e., from hours to a few minutes. High-pressure resistant devices were recently fabricated and used to generate stable droplets from pressurized fluids such as supercritical fluid-liquid systems. We believe that supercritical microfluidics is a promising tool to develop sustainable processes in chemistry.

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