Biogenic calcite particles from microalgae-Coccoliths as a potential raw material.

Synthetic calcite (CaCO) particles are found in a broad range of applications. The geometry of particles produced from limestone or precipitation are versatile but limited to basic shapes. The microalga produces micro-structured calcite platelets, called coccoliths.

Turbidimetric method for the determination of particle sizes in polypropylene/clay-composites during extrusion.

Nanocomposites with polypropylene as matrix material and nanoclay as filler were produced in a double twin screw extruder. The extrusion was monitored with a spectrometer in the visible and near-infrared spectral region with a diode array spectrometer. Two probes were installed at the end at the extruder die and the transmission spectra were measured during the extrusion.