Collect. Czech. Chem. Commun. 1995, 60, 1935-1940

Density Measurements of Annealed Amorphous Polymers

František Lednický

Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6, Czech Republic


The flotation method of the density measurement was adapted to reach sufficient accuracy with which the differences due to annealing amorphous polymers above their glass transition temperature can be traced. The densities of amorphous poly(methyl methacrylate) and polystyrene increase logarithmically in the course of the annealing, which suggests that some arrangement or ordering takes place. However, the changes are not stable.