2. Material andmethods
2.1. Plastic material
Plastic testmaterialswere chosen according tomost commonly used
andmost abundant polymer types in freshwater systems. PE of lowdensity
(ρ = 0.92 g/ml), PP and PVC were purchased from Sigma-Aldrich.
PA, PES, PET and PUwere derived fromplastic packing materials, pellets
and products. The purity of the materials was given by their certificates
(PE, PVC and PP) and product labels. Any impurity with a plastic material other than the ones described above would have been observable
in later analysis with TGA-DSC, which was however not the case.
PA was only available asmixture of bothwith PES as fibers, but showed
clearly identifiable peaks and was therefore adopted (Fig. 1). All materials
were mechanically powdered to a particle size b200–500 μm
using mills and graters prior to analysis since i) large particle sizes can
cause interference in terms of lower reactivity and peak overlaying in
TGA-DSC analysis and ii) only small amounts are weighed in the TGADSC
pans (ca. 1 to 20 mg plastic).