Ways towards novel CaCO3 composites – how inorganic, synthetic and biological macromolecular additives influence crystallizationWednesday (10.05.2017) 10:00 - 10:20 Part of:
CaCO3 with its industrial importance as major source of water hardness, as mineral filler or raw material for construction chemicals is a widely used inorganic model system to study the effect of additives (e.g. polymers) on the crystallization behavior. The presented polymer wa synthesized via CROP (cationic ring opening polymerization) of cyano ethylene oxide (CEO) with THF. Post-modification by oxidation of cyano groups this polymer results in a polymer with high backbone apolarity while rather small amounts of 8.4% carboxylic groups ensusre solubility and strong inhibition of CaCO3 crystallization with linear dependence between polymer concentration and resulting crystals size.
For a hyperbranched analogon the CROP was facilitated with AB3 monomer 3,3-bis(hydroxymethyl)oxetane (BHMO) and THF with subsequent introduction of succinic acid molecules as carboxylic acid functional groups. Surprisingly dumbbell shape with rough surfaced mesocrystaline CaCO3 crystals are crystallization result with these hyperbranched polymers. These hyperbranched or even linear polyTHF polyacids represent a class of polymers on the apolar playground of polyacids prove that molecule shape so resulting intramolecular distance of functional groups in a detergent influences the pathway of CaCO3 precipitation more than polarity of molecule backbones which might open a new pathway of industrial detergents research.