LAUSR

Abstract A facile procedure to fabricate the hydrophobic surfaces of calcium carbonate-polymer composites has been well described. Nano-sized highly ordered CaCO3 clusters i.e. calcite/vaterite have been synthesized by simple precipitation in the presence of template made of cationic surfactant: cetyl trimethyl ammonium bromide (CTAB) and different non-ionic amphiphilic triblock copolymers comprising of PEO–PPO–PEO units: F98 and F127 commercially known as Pluronics® or Synperonics® or Poloxamers. The morphology of these nano-composites so formed was characterized in detail using spectroscopy, microscopy, diffraction, and scattering techniques. It was found that the surfactant-polymer prototype turned out to be an important parameter to tune and understand the shape-controlled morphology and crystallization in precipitated calcium carbonate (PCC). Our diffraction pattern depicted the presence of calcite/vaterite, while the microscopic investigations indicated the bunch/clusters of calcite (nano-flakes) arranged in stacks which could be attributed to the attractive hydrophobic interaction between the alkyl group of cationic surfactant and -PPO unit of the block copolymer. Similar assumptions were inferred by structural optimization using Gauss View 5.0.9. The scattering measurements described the polydispersity of nano-aggregates based on the scattering intensity. Results expounded the growth mechanism of CaCO3 crystals to be a step-by-step build process with respect to the polarity.