| Abstract
| - The effect of temperature on the association of graft copolymers of poly(l-lysine)-graft-poly(N-isopropylacrylamide), PLL-g-PNIPAM, in water was investigated by light scattering methods and electronmicroscopy. It was found that the thermosensitive graft copolymers form monodisperse particles abovethe phase transition temperature of PNIPAM blocks (31 °C). The hydrodynamic radii (Rh) and molecularweights of supramolecular particles were strongly concentration-dependent. The larger particles (Rh ≈130−240 nm) were observed at concentrations above 0.1 mg/mL whereas smaller and more compact particles(Rh ≈ 60−80 nm) were observed at concentrations below 0.1 mg/mL. The molecular weight of the particlesincreased with increasing content and molecular weight of PNIPAM grafts. The small monodisperse particlesobserved at low concentrations are probably swollen micelles, and particles observed at high concentrationsare their aggregates.
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