The synthesis and aggregation behavior of well‐defined thermosensitive (co)polymers of oligo(ethylene glycol) methacrylates (POEGMA) in aqueous solutions were investigated. The cloud points of the POEGMAs solutions were determined by turbidimetry and dynamic light scattering. For POEGMA (co)polymers the cloud point temperature (TCP) increased linearly with increasing content of more hydrophilic comonomer. The mesoglobules formed by POEGMAs in dilute aqueous solutions above TCP were studied by light scattering. The size of mesoglobules depended on the concentration and the heating procedures. The aggregates became smaller with decreasing initial concentration of polymer and increasing rates of temperature change. By selecting the proper heating and dilution procedures, the influence of the (co)polymer structure on the size of the mesoglobules could be determined. The size of the mesoglobules decreased with the length of the OEG side chains and increased with increasing content of more hydrophilic comonomer. The light scattering parameters of the mesoglobules—A2 values and shape factors ${R_{\rm g}\over R_{\rm h}}$—suggested that the hydrophilic OEG side chains placed at the periphery of the mesoglobules in direct contact with the surrounding water controlled the size of mesoglobules and their stability. Shape factors for all POEGMA mesoglobules indicated that the mesoglobules remained highly hydrated after formation. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013

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Well-defined thermosensitive poly[tri(ethylene glycol) monoethyl ether methacrylate] (P(TEGMA-EE)) brushes were synthesized on a solid substrate by the surface-initiated atom transfer radical polymerization of TEGMA-EE. The polymerization reaction was initiated by 2-bromo-2-methylpropionate groups immobilized on the surface of the wafers. The changes in the surface composition, morphology, philicity, and thickness that occurred at each step of wafer functionalization confirmed that all surface modification procedures were successful. Both the successful modification of the surface and bonding of the P(TEGMA-EE) layer were confirmed by X-ray photoelectron spectroscopy (XPS) measurements. The thickness of the obtained P(TEGMA-EE) layers increased with increasing polymerization time. The increase of environmental temperature above the cloud point temperature of P(TEGMA-EE) caused the changes of surface philicity. A simultaneous decrease in the polymer layer thickness confirmed the thermosensitive properties of these P(TEGMA-EE) layers. The thermosensitive polymer surfaces obtained were evaluated for the growth and harvesting of human fibroblasts (basic skin cells). At 37 °C, seeded cells adhered to and spread well onto the P(TEGMA-EE)-coated surfaces. A confluent cell sheet was formed within 24 h of cell culture. Lowering the temperature to an optimal value of 17.5 °C (below the cloud point temperature of the polymer, TCP, in cell culture medium) led to the separation of the fibroblast sheet from the polymer layer. These promising results indicate that the surfaces produced may successfully be used as substrate for engineering of skin tissue, especially for delivering cell sheets in the treatment of burns and slow-healing wounds.