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Pulsed laser polymerization coupled with size exclusion chromatography (PLP-SEC) was implemented to study the micellar radical homopropagation kinetics of cationic surfmer, polycaprolactone choline iodide ester methacrylate (PCL n ChMA with n = 2 average polyester units), at concentrations of 5, 10, and 20 wt% in aqueous solutions at 25, 50, 70, and 85 °C. PCL 2 ChMA can propagate in both aqueous and compartmentalized phases, with the relative importance of the two reaction loci changing with temperature. As the corresponding saturated macromonomer concentration, [ M ], inside the growing polymeric micelles cannot be easily determined, only the product of propagation rate coefficient ( k p ) and [ M ] are measured by PLP-SEC; at 25 °C, a minimum k p of 863 ± 95 L mol −1 s −1 is estimated assuming bulk [ M ]. (Macro)monomer composition drifts for batch acrylamide (AM)/PCL n ChMA micellar copolymerizations in D 2 O at 50 °C are well represented by the apparent reactivity ratios r AM = 0.31 ± 0.03 and r PCL3ChMA = 8.79 ± 0.38. [ABSTRACT FROM AUTHOR]

Micellar radical polymerization of a short-chain polyester macromonomer, polycaprolactone choline iodide ester methacrylate (PCL nChMA), is used to produce a new cationic flocculant that becomes more hydrophobic in response to hydrolytic degradation. The cationic tips of the comb-like poly(PCL3ChMA) accelerate the settling rate of oil sands tailings, while partial hydrolysis of the polyester grafts reveals the hydrophobic segments that reduce capillary suction time by 30%. This technology combines the material properties of polyesters with the productivity of radical polymerization to make dual functional flocculants with characteristics that can be easily tuned to control flocculation performance, such as polymeric cation density, hydrophobic content, and polymer architecture. [ABSTRACT FROM AUTHOR]

In this work PEGylated polyester-basednanoparticles (NPs) fordrug delivery applications were synthetized through emulsion freeradical polymerization. These NPs are produced starting from functionalizedmacromonomers whose average chain length can be tuned in a controlledway. Since the degradation of these NPs occurs through the hydrolysisof side chains, by tuning their length it is possible to obtain NPswith a controllable degradation time, comparable to data obtainedwith NPs internalized into cells. The long-term colloidal stabilityof these NPs in isotonic environment has been assessed through dynamiclight scattering measurements and their degradation rate in cell mediumhas been proved to be fast and controllable. The NP behavior in gastricand intestinal solution was also studied. [ABSTRACT FROM AUTHOR]