Thermo‐Responsive Copolymers Based on Poly(N‐isopropylacrylamide) and Poly[2‐(methacryloyloxy)ethyl phosphorylcholine]: Light Scattering and Microscopy Experiments
1. Departamento de Química, Universidade Federal de Santa Catarina, 88040‐900 Florianópolis, SC, Brazil;2. Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S3 7HF, UK;3. Centre de Recherches sur les Macromolécules Végétales (CERMAV‐CNRS), affiliated with Joseph Fourier University, BP 53, F‐38041, and ICMG FR 2607, Grenoble cedex 9, France
Abstract:
Aqueous self‐assembly of thermosensitive triblock copolymers based on poly(N‐isopropylacrylamide) and poly[2‐(methacryloyloxy)ethyl phosphorylcholine] (PNIPAMm–PMPCn–PNIPAMm and PNIPAMm–PMPCn–S–S–PMPCn–PNIPAMm) were studied using light scattering (SLS and DLS), TEM and fluorescence experiments. These techniques were used to investigate the morphological transition as a function of the temperature, below and above the LCST of the PNIPAM, at various triblock copolymer concentrations ranging from dilute to semi‐dilute regimes. Below the LCST and at low concentrations, aqueous solutions show micellar behavior, while above the LCST self‐assembly leading to large nanoparticles stabilized with PMPC chains. Such behavior is the onset of a gel‐like phase transition observed at higher concentrations.
