Chemically crosslinked hydrogels composed of carbohydrate‐based and thermoresponsive monomers, sucrose 1‐O′‐methacrylate (SMA), sucrose dimethacrylate, and N‐isopropylacrylamide, respectively, were synthesized by free radical polymerization. These materials were characterized with respect to their composition, thermoresponsiveness, porosity, degradability, and as drug and protein delivery systems. Swelling studies, thermomechanical analysis, and differential scanning calorimetry showed that the lower critical solution temperature behavior of the hydrogels can be controlled by the SMA amount in the copolymers. On the other hand, thermoporometry showed that the pore size is somewhat dependent on the composition, which is confirmed by scanning electron microscopy. Hydrolytic degradation studies indicated that SMA side chains, as well as the crosslinker (sucrose dimethacrylate), are hydrolysable at corporeal temperature and pH 10, and the water swelling capability of the resulting materials increases as the hydrolysis degree increases. Finally, protein delivery studies revealed that the kinetics of release can be tailored by the copolymer composition. The results of this study suggest the potential application of these hydrogels in drug delivery systems and tissue engineering. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45495.

Using a combination of modeling and experiments, we show that miktoarm star macromolecules act as molecular/mechanical linkers in the fabrication of multilayer stackable gels, which are formed by sequential controlled radical polymerization of successive layers in incompatible solvents. Dissipative particle dynamics simulations indicate that miktoarm star copolymers localize at the interface between the incompatible solvents and act as molecular bridging agents between the respective gel layers. Miktoarm stars composed of poly(n-butyl acrylate)-co-poly((oligo(ethylene glycol) methacrylate) were synthesized by atom transfer radical polymerization (ATRP) and successfully used as an interfacial compatibilizer/linker in mechanically interconnected bilayer stacks comprised of a primary layer of cross-linked hydrophobic n-butyl methacrylate polymerized in toluene and of a secondary layer of crosslinked hydrophilic 2-(dimethylamino)ethyl methacrylate polymerized in water. Without the miktoarm stars, no connection between the two layers could be obtained.

Stackable gels comprised of layers of dissimilar polymers were synthesized by combining conventional free radical polymerization (FRP) and atom transfer radical polymerization (ATRP) using two approaches: (i) polymerization of a pre-gel solution containing a monomer and cross-linker introduced on top of a previously prepared gel, and (ii) simultaneous polymerization of two immiscible pre-gel solutions remaining in contact. All permutations of FRP and ATRP yielded single-piece, connected, amphiphilic gels regardless of the order of polymerization. Furthermore, multi-layer ATRP gels combining different polymers were synthesized with the FRP layer as a gluing agent. A 10-layer amphiphilic stackable gel combining n-butyl methacrylate (BMA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA), and a 10-layer stackable gel combining BMA, DMAEMA and di(ethylene glycol) methyl ether methacrylate (PEO 2 MA) were synthesized. This patching method, combining conventional FRP gels with ATRP ones, offers an efficient path to the formation of complex stackable gel architectures.

Herein, we present the synthesis and characterization of block copolymers based on poly(2-ethyl-2-oxazoline), a biocompatible and stealth polymer that has drawn considerable attention in biomedical-related applications, and poly(4-vinylpyridine), a polydentate...

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