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Temperature responsive poly(ethoxytriethyleneglycol acrylate) (PETEGA) of Mn ¼ 8000 and M w /M n ¼ 2.30 was synthesized by ATRP. Dilute aqueous solutions of PETEGA exhibit lower critical solution temperature (LCST) at around 34 8C. We found that PETEGA can form nano-sized uniform colloidal aggregates (50-200 nm) above LCST either with or without an additional surfactant. Therefore PETEGA nanoaggregates were used as templates for the seeded free radical copolymerization of acrylamides or methacrylates together with a cross-linker to form acrylamide or methacrylate based core-shell particles. The formation of the PETEGA templates was investigated by dynamic light scattering (DLS) in order to find optimal conditions for obtaining narrow dispersed aggregates of desired sub-micron dimensions. Core-shell particles were characterized by DLS and scanning electron microscopy.

Two new families of biodegradable poly[(ε-caprolactam)-co-(ε-caprolactone)] and poly[(ε-caprolactam)-co-(δ-valerolactone)] copolymers were synthesized via anionic polymerization. The polymerization was activated with macroactivators (MAs) based on telechelic poly(ε-caprolactones) (PCLOs) and poly(δ-valerolactone) (PVLO) polyols. The molecular weights of the polyesters were varied to obtain a large diversity of copolymer structures and properties. The MAs were prepared by reaction of reactive hydroxyl end-groups of PCLO polyols or hydroxyl-carboxyl end-groups PVLO polyol with isophorone diisocyanate (IF). The diisocyanate-end-capped poly(lactones) were additionally blocked in situ with ε-caprolactam to receive corresponding carbamoyllactam derivates. Analyses of the isolated products by FTIR, 1 H NMR spectroscopy, and size exclusion chromatography indicated that nearly quantitative