Poly( N-vinylcaprolactam) microgels. Polymeric stabilization with poly(vinyl Talcohol)

Poly(vinyl alcohol), PVA, with different molecular weights, Mw, and degrees of hydrolysis has been used to study the steric stabilization of microgels based on poly(N-Avinylcaprolactam). The stabilizer influences the particle size and stability, but has no influence on the thermal properties. The thermal behavior of microgels depends on the heating rate: slow heating leads to the formation of aggregates and fast heating to an intramolecular collapse. The aggregates showed an unusual angular dependence of the A diffusion coefficient, which can be explained by the presence of probably an additional rotational diffusion.