Preparation of fine particles of poly(N-vinyl-2-pyrrolidone-co-2-methylene-1,3-dioxepane) using supercritical antisolvent

New Insights into Acrylic Polymer Precipitation by Supercritical Fluids

“…The results revealed that, with increasing temperature (and thus decreasing density), the mean particle size was increased due to the plasticizing effect of SC-CO 2 [20]. A similar tendency was found by other authors in the precipitation of other biopolymers with the SAS process [21][22][23][24][25]. The variation of the particle size with the pressure is more complex: First, the particle size increases with pressure; it goes through a maximum at about 150 bar and then decreases slightly, as can be seen in Tab.…”

“…However, the precipitation of other acrylic polymers using the SC-CO 2 antisolvent process seemed to be independent of the pressure in the range of 8-12.5 MPa, at a fixed temperature of 40°C [15]. Even as the pressure increased, the mean particle size became smaller during the processing of other polymers [24,25].…”

Controlling the synthesis of degradable vinyl polymers by xanthate-mediated polymerization

“…These include hydrophobic monomers such as ethylene, 14 styrene (Sty), [14][15][16][17][18][19] acrylonitrile (AN), 19,20 vinyl acetate (VAc), [21][22][23] and methyl methacrylate (MMA) 20,24,25 as well as hydrophilic monomers such as poly(ethylene glycol) methyl ether methacrylate (PEGMA), 26,27 N,N-dimethylaminoethyl methacrylate (DMAEMA), [28][29][30] N-isopropylacrylamide (NIPAM), 31,32 and N-vinylpyrrolidone (NVP). 33,34 However, with the exception of less activated monomers (LAMs) such as VAc, the reactivity ratios for these copolymerizations indicate that final polymer compositions are more gradient-like or blocky, not statistical. 17,25,29,35 Control of polymerizations incorporating CKAs has also been attempted through reversible-deactivation radical polymerization (RDRP) techniques such as Nitroxide-Mediated Polymerization (NMP), 19,36 Atom Transfer Radical Polymerization (ATRP), [37][38][39] and Reversible Addition-Fragmentation Chain-Transfer Polymerization/Macromolecular Design by Interchange of Xanthates (RAFT/MADIX) 40 but there are only a handful of examples where these techniques have been used to control copolymerizations with MDO.…”

Mapping the characteristics of the radical ring‐opening polymerization of a cyclic ketene acetal towards the creation of a functionalized polyester

“…Free radical copolymerization of MDO with various vinyl monomers such as vinyl acetate,10 styrene,10, 13, 14 methyl acrylate,15 methyl methacrylate,10, 16 dimethyl vinylphosphonate,17 and fluorohexene18 has also been performed. Copolymers of MDO and N ‐vinyl‐2‐pyrrolidone19 as well as temperature‐responsive biodegradable hydrogels of MDO and N ‐isopropylacrylamide20 have been synthesized for use in biomedical applications.…”