A kind of preparation method of polymer breathable film and filler ground calcium carbonate

Abstract

The invention provides a polymeric gas-permeable membrane and a preparation method of a filler heavy calcium carbonate of the polymeric gas-permeable membrane, belongs to the field of water absorbing materials, and particularly relates to a low-water content heavy calcium carbonate filler for the polymeric gas-permeable membrane and a preparation method of the filler. Heavy calcium carbonate is ground into particles of which the particle size is in the level that the 325-mesh sieve residues are less than 3%, size mixing is conducted, wet-type grinding is conducted, the ground materials are prepared into a filter cake through filter pressing and dewatering, drying and organic surface modifying are simultaneously conducted in a superfine drying pulverizer, vacuum packaging is conducted, and the filter cake is combined with an organic polymer to prepare the microporous gas-permeable membrane. The adopted heavy calcium carbonate filler is low in water content, fine in particle size distribution, good in compatibility with the polymer, easy to disperse and high in binding force with the organic polymer, and the gas-permeable membrane prepared from the filler is good in water vapor permeability, high in tensile strength and elongation rate and low in production cost.

Description

technical field [0001] The invention belongs to the field of water-absorbing materials, and in particular relates to a low-water-content ground calcium carbonate filler for a polymer breathable film and a preparation method thereof. Background technique [0002] Microporous air-permeable film is a kind of inorganic filler-filled polymer composite film material with a micro-pore structure. The micro-pores allow gas to pass through, but are blocked because the diameter of the liquid is larger than the diameter of the micro-pores, so it has the characteristics of "breathable and impervious to water". The manufacturing process of the breathable film is to compound the inorganic filler and the polymer to obtain the special material for the breathable film; finally, the special material is cast or blown into a film; finally, the film is stretched to separate the polymer matrix from the surface of the filler particles to form a microscopic film. Pores, and interconnected micro-pore...

AI Technical Summary

Problems solved by technology

However, in this technical scheme, CaCO 3 Excess moisture on the surface will evaporate at a higher processing temperature to generate water vapor, resulting in large pores or even holes on the surface of the breathable film, which will affect the moisture permeability and mechanical properties of the breathable film; the drying and surface of nano-calcium carbonate The modification process is carried out separately, and in the production gap between drying and surface modification, CaCO 3 Will absorb moisture in the air, making the final output of CaCO 3 The moisture content of the filler cannot meet the use requirements; the preparation method of nano-calcium carbonate is relatively complicated, and the cost of the product is still high, so the cost of hygienic products for water-absorbing materials cannot be significantly reduced