Preparation method of submicron order granule type calcium carbonate for plastics

Abstract

The invention discloses a preparation method of submicron order granule type calcium carbonate for plastics. The preparation method of the submicron order granule type calcium carbonate for the plastics comprises the steps that limestone is crushed and calcinated to obtain quick lime, a digestion reaction is carried out on the quick lime to obtain lime slurry, waste residues are removed by a 80-mesh sieve, 24-hour aging is carried out on the lime slurry to obtain refined lime milk, and standby application is carried out; the refined lime milk is introduced into a bubbling carbonation reactionkettle, the starting carbonation temperature of the lime milk is controlled at 30-45 DEG C, stirring is started, polymaleic anhydride is added, mixed gas containing the CO2 concentration is introducedfor carbonation reaction, ammonium chloride is introduced in batches in the carbonation process, sodium polyacrylate is added at 45-60 min of the carbonization late period, and air introducing is stopped when reaction system pH is 7.5, the carbonation reaction is stopped, and calcium carbonate suspension liquid is obtained; and a calcium carbonate product with the specific area of 9-16m<2> / g is obtained through dehydration, drying and smashing. The calcium carbonate is narrow in granulometric distribution, uniform in morphology and uniform in granular size, the submicron order granule type precipitated calcium carbonate with the uniform granular size is applied to the plastics, and the mechanical property of the submicron order granule type precipitated calcium carbonate can be obviouslyimproved.

Description

technical field [0001] The invention relates to the technical field of calcium carbonate, in particular to a method for preparing submicron rice grain-shaped calcium carbonate for plastics. Background technique [0002] Calcium carbonate is an important inorganic material and a typical biomineral. It has stable chemical properties and good biocompatibility. It has been widely used in papermaking, plastics, ink, medicine, cosmetics and many other industries. Adding an appropriate amount of inorganic filler calcium carbonate in plastic processing can endow the plastic with high strength, high hardness, wear resistance, aging resistance, flame retardancy, corrosion resistance, easy dyeing and other characteristics, and can reduce production costs. But in general, due to the poor dispersion of calcium carbonate products and large particle size, the physical and mechanical properties of the added plastic products are reduced, the color difference is unstable, and the fluctuation ...

AI Technical Summary

Problems solved by technology

This method adopts the causticization step to prepare cheap spindle-shaped or rice-shaped calcium carbonate with a mixed morphology, but the product obtained by this method has a wide particle size distribution and uneven crystal morphology, and generally only can obtain a small diameter of 0.3-1.5 um and spindle-shaped or rice-shaped calcium carbonate with a large diameter of 0.7-7um, which is not conducive to improving the performance of plastic products

[0007] To sum up, the current production of precipitated calcium carbonate is mainly faced with the problems of complex production process, high cost, difficult crystal shape control, wide particle size distribution of the product, and different particle sizes, which greatly affects the later stage of precipitated calcium carbonate. Applications

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