Polymer induced changes of the crystallization scenario in suspensions of hard sphere like microgel particles.
We investigated the crystallization scenario of highly cross linked polystyrene particles dispersed in the good solvent 2-ethylnaphtalene and their mixtures with non-adsorbing low molecular weight polysterene polymer using time resolved static light scattering. The samples were prepared slightly below the melting volume fraction of the polymer free system. For the polymer free samples, we obtained polycrystalline solids via crystallization scenario known from hard sphere suspensions with little competition of wall crystal formation. Addition of non-adsorbing low molecular weight polystyrene polymer leads to a considerably slowing down of the bulk crystallization kinetics. We observed a delay of the precursor to crystal conversion for the bulk crystallization while the induction times for the wall nucleation are reduced. The increased polymer concentration thus shifts the balance between the two competing crystallization pathways giving the possibility to tune the relative amount of wall based crystals.
Institut für Physik, Johannes Gutenberg Universität, D-55099 Mainz, Germany.
Richard
R
Beyer
Sara
S
Iacopini
Thomas
T
Palberg
Hans Joachim
HJ
Schöpe