The ability of poly(acrylic acid) (PAA) with different end groups and molar masses prepared by Atom Transfer
Radical Polymerization (ATRP) to inhibit the formation of calcium carbonate scale at low and elevated temperatures
was investigated. Inhibition of CaCO3 deposition was affected by the hydrophobicity of the end groups of
PAA, with the greatest inhibition seen for PAA with hydrophobic end groups of moderate size (6–10 carbons).
The morphologies of CaCO3 crystals were significantly distorted in the presence of these PAAs. The smallest
morphological change was in the presence of PAA with long hydrophobic end groups (16 carbons) and the relative
inhibition observed for all species were in the sameorder at 30 °C and 100 °C. Aswell as distorting morphologies,
the scale inhibitors appeared to stabilize the less thermodynamically favorable polymorph, vaterite, to a
degree proportional to their ability to inhibit precipitation.