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The copolymerization of glycidyl cinnamate (GC) as a hitherto non‐polymerizable, photoreactive epoxide structure to aliphatic polyether copolymers is described, using the monomer‐activated epoxide ring‐opening polymerization (MAROP). Ethoxyethyl glycidyl ether (EEGE) and GC are copolymerized employing triisobutylaluminum (i‐Bu3Al) as a catalyst and tetraoctylammonium bromide (NOctBr4) as an initiator. The amount of GC varies from 3 mol% to 100 mol%, which results in apparent molecular weights in the range of 2600 to 4600 g mol−1 and dispersities (Đ) below 1.34. Studies of the microstructure by in‐situ 1H NMR kinetics indicate a gradient‐like distribution of EEGE and GC (reactivity ratios: rEEGE = 0.28; rGC = 3.6), applying the ideal copolymerization model for evaluation. A tentative explanation relies on differing bond lengths in the respective epoxide rings, as suggested by density functional theory (DFT) calculations. Mild and selective cleavage of the acetal protecting groups of EEGE is achieved using the acidic ionic resin Dowex, leaving the GC ester bonds intact (Mn = 1900–3700 g mol−1, Đ < 1.34). Thermal properties of the copolymers and the PGC homopolymer are investigated by differential scanning calorimetry (DSC). The crosslinking of P(G‐co‐GC) copolymers by UV irradiation allows hydrogel formation, which is confirmed by IR spectroscopy. [ABSTRACT FROM AUTHOR]

PEG is the gold standard polymer for pharmaceutical applications, however it lacks degradability. Degradation under physiologically relevant pH as present in endolysosomes, cancerous and inflammatory tissues is crucial for many areas. The authors present anionic ring-opening copolymerization of ethylene oxide with 3,4-epoxy-1-butene (EPB) and subsequent modification to introduce acid-degradable vinyl ether groups as well as methacrylate (MA) units, enabling radical cross-linking. Copolymers with different molar ratios of EPB, molecular weights (M n ) up to 10 000 g mol -1 and narrow dispersities (Đ<1.05) were prepared. Both the P(EG-co-isoEPB)MA copolymer and the hydrogels showed pH-dependent, rapid hydrolysis at pH 5-6 and long-term storage stability at neutral pH (pH 7.4). By designing the degree of polymerization and content of degradable vinyl ether groups, the release time of an entrapped protein OVA-Alexa488 can be tailored from a few hours to several days (hydrolysis half-life time t 1/2 at pH 5: 13 h to 51 h)., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Glycidyl tosylate appears to be a non-polymerizable epoxide when nucleophilic initiators are used because of the excellent leaving group properties of the tosylate. However, using the monomer-activated mechanism, this unusual monomer can be copolymerized with ethylene oxide (EO) and propylene oxide (PO), respectively, yielding copolymers with 7-25 % incorporated tosylate-moieties. The microstructure of the copolymers was investigated via in situ 1 H NMR spectroscopy, and the reactivity ratios of the copolymerizations have been determined. Quantitative nucleophilic substitution of the tosylate-moiety is demonstrated for several examples. This new structure provides access to a library of functionalized polyethers that cannot be synthesized by conventional oxyanionic polymerization., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

An ideal random anionic copolymerization is forced to produce gradient structures by physical separation of two monomers in emulsion compartments. One monomer (M) is preferably soluble in the droplets, while the other one (D) prefers the continuous phase of a DMSO-in-cyclohexane emulsion. The living anionic copolymerization of two activated aziridines is thus confined to the DMSO compartments as polymerization occurs selectively in the droplets. Dilution of the continuous phase adjusts the local concentration of monomer D in the droplets and thus the gradient of the resulting copolymer. The copolymerizations in emulsion are monitored by real-time 1 H NMR kinetics, proving a change of the reactivity ratios of the two monomers upon dilution of the continuous phase from ideal random to adjustable gradients by simple dilution., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)