阅读说明：本技术 一种制备造纸用方解石粉的方法 (Method for preparing calcite powder for papermaking ) 是由 韦明 于 2020-04-30 设计创作，主要内容包括：本发明公开了一种制备造纸用方解石粉的方法,将方解石粉碎成方解石粉；以脂肪酸盐、淀粉、羊毛脂琥珀酸酯磺酸钠及三异硬脂酰基钛酸异丙酯作为第一改性剂,加入热水,配成第一改性液；将方解石粉输送和第一改性液输送至高速分散均质机,均质处理；均质处理后的方解石粉输送至表面改性机,加入聚氯代对二甲苯和八乙烯基八硅倍半氧烷组进行二次表面改性,经干燥,得造纸用方解石粉。本方法改性后的方解石粉不仅能够改善分散性、相容性,提高与纤维的结合力,还具有优异防潮防霉性能,作为造纸填料时不仅能够提高纸张表面的平滑度和光泽度,提高填料在纸张中的留着率和填充量,还能提高纸张的防潮防霉性能,使得纸张能够长时间完整保存。(The invention discloses a method for preparing calcite powder for papermaking, which comprises the following steps of crushing calcite into square limestone powder; taking fatty acid salt, starch, lanolin sodium succinate sulfonate and triisostearoyl isopropyl titanate as first modifying agents, and adding hot water to prepare first modifying liquid; conveying calcite powder and the first modification liquid to a high-speed dispersion homogenizer, and homogenizing; and (3) conveying the homogenized calcite powder to a surface modifying machine, adding polychlorinated p-xylene and octavinyl octasilsesquioxane groups for secondary surface modification, and drying to obtain the calcite powder for papermaking. The calcite powder modified by the method can improve the dispersibility and compatibility, improve the binding force with fibers, has excellent moisture-proof and mildew-proof properties, and can improve the smoothness and glossiness of the surface of paper, improve the retention rate and filling amount of filler in the paper and the moisture-proof and mildew-proof properties of the paper when used as a paper filler, so that the paper can be completely stored for a long time.)

1. A method for preparing calcite powder for papermaking is characterized in that: the method comprises the following steps:

(1) adding calcite into a grinder, and grinding to obtain calcite powder, wherein the particle size of the calcite powder is less than or equal to 45 mu m;

(2) taking fatty acid salt, starch, lanolin sodium succinate sulfonate and triisostearoyl isopropyl titanate as first modifiers, wherein the dosage of the first modifiers is 2-4% of the weight of calcite powder, and adding hot water into the first modifiers to prepare first modified liquid; conveying calcite powder and the first modified liquid to a high-speed dispersion homogenizer, and homogenizing for 20-30 nin;

(3) conveying the homogenized calcite powder to a surface modifying machine, adding a second modifying agent consisting of polychlorinated p-xylene and octavinyl octasilsesquioxane for surface modification for 10-20min, wherein the dosage of the second modifying agent is 0.5-1.5% of the weight of the calcite powder, and drying to obtain the calcite powder for papermaking.

2. The method for preparing calcite powder for papermaking according to claim 1, characterized in that: the first modifier comprises fatty acid salt, starch, lanolin sodium succinate sulfonate and triisostearoyl isopropyl titanate in a mass ratio of 1-3:5-10:0.5-2: 1-3.

3. The method for preparing calcite powder for papermaking according to claim 2, characterized in that: the fatty acid salt comprises one or more of sodium stearate, sodium palmitate and sodium myristate.

4. The method for preparing calcite powder for papermaking according to claim 1, characterized in that: the adding amount of the hot water in the step (2) is 3-5 times of the weight of the first modifier; the hot water is hot water with the temperature of 70-90 ℃.

5. The method for preparing calcite powder for papermaking according to claim 1, characterized in that: the mass ratio of the poly (chlorinated p-xylene) to the octavinyl octasilsesquioxane in the second modifier is 1: 0.5-1.5.

6. The method for preparing calcite powder for papermaking according to claim 1, characterized in that: the homogenization treatment is carried out at the temperature of 300-500 r/min.

7. The method for preparing calcite powder for papermaking according to claim 1, characterized in that: the drying is realized by adopting a pulse airflow dryer.

8. The method for preparing calcite powder for papermaking according to claim 7, characterized in that: the feeding speed of the pulse airflow dryer is 200-300kg/h, the drying temperature is 80-110 ℃, and the air speed is 10-15 m/s.

Technical Field

The invention relates to the technical field of preparation of non-metallic mineral fillers, in particular to a method for preparing calcite powder for papermaking.

Background

Calcite powder is generally used as a filler and widely applied to daily chemical industries such as artificial floor tiles, rubber, plastics, papermaking, coatings, paints, printing inks, cables, building products, food, medicine, textile, feed, toothpaste and the like. Calcite has a wide application prospect in the paper industry due to its high whiteness, high opacity, low price, abundant reserves, wide sources and the like.

In the paper industry, calcite is used as a filler of paper products, so that the heat resistance, wear resistance, dimensional stability, rigidity and processability of paper can be improved, the cost of the paper is reduced, but the surface of calcite has hydroxyl groups with strong hydrophilicity and strong alkalinity, and the hydrophilicity and the lipophobicity ensure that calcium carbonate and organic high polymer have poor hydrophilicity and are easy to form aggregates, so that the calcium carbonate and the organic high polymer are unevenly dispersed in the high polymer, interface defects between the two materials are caused, and the direct application effect is poor. The technical development of calcite fillers is becoming more extensive and intensive, but the technologies that can be used for the production of base paper are really limited, which mainly presents several problems: firstly, the process of calcite filler modification is complex, the agglomeration problem still exists, and the cost is too high; secondly, the effect of calcite filler modification is not obvious, and the strength performance of paper is greatly reduced along with the addition of the filler; thirdly, the modified filler has poor stability and weak bonding force between calcite and fibers, so that the retention rate of the filler in paper is low, the loss is serious, the utilization rate of raw materials is low, and the wastewater treatment capacity and the treatment cost are increased. And secondly, the common paper has poor moisture resistance, and if the common paper is stored improperly for a long time, the common paper is easy to regain moisture and mildew, so that the common paper cannot be normally used.

Disclosure of Invention

The invention provides a method for preparing calcite powder for papermaking, aiming at overcoming the defects of calcite in papermaking. According to the method, the talcum powder is modified by adopting the fatty acid salt, the starch, the lanolin sodium succinate sulfonate and the triisostearoyl isopropyl titanate, so that the dispersibility and the compatibility of the talcum powder can be improved, and the binding force with the fiber is improved; and modifying the calcite for the second time by using the polychlorinated p-xylene and the octavinyl octasilsesquioxane, so that the moisture and mildew resistance of the filler can be improved.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

in order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

a method for preparing calcite powder for papermaking, comprising the following steps:

(1) adding calcite into a grinder, and grinding to obtain calcite powder, wherein the particle size of the calcite powder is less than or equal to 45 mu m;

(2) taking fatty acid salt, starch, lanolin sodium succinate sulfonate and triisostearoyl isopropyl titanate as first modifiers, wherein the dosage of the first modifiers is 2-4% of the weight of calcite powder, and adding hot water into the first modifiers to prepare first modified liquid; conveying calcite powder and the first modified liquid to a high-speed dispersion homogenizer, and homogenizing for 20-30 nin;

(3) conveying the homogenized calcite powder to a surface modifying machine, adding a second modifying agent consisting of polychlorinated p-xylene and octavinyl octasilsesquioxane for surface modification for 10-20min, wherein the dosage of the second modifying agent is 0.5-1.5% of the weight of the calcite powder, and drying to obtain the calcite powder for papermaking.

Furthermore, the mass ratio of the fatty acid salt, the starch, the lanolin sodium succinate sulfonate and the triisostearyl isopropyl titanate in the first modifier is 1-3:5-10:0.5-2: 1-3.

Further, the fatty acid salt comprises one or more of sodium stearate, sodium palmitate and sodium myristate.

Further, the adding amount of the hot water in the step (2) is 3-5 times of the weight of the first modifier; the hot water is hot water with the temperature of 70-90 ℃.

Further, the mass ratio of the poly (chlorinated p-xylene) to the octavinyl octasilsesquioxane in the second modifier is 1: 0.5-1.5.

Further, the homogenization treatment is carried out at 300-500 r/min.

Further, the drying is drying by using a pulse airflow dryer.

Further, the feeding speed of the pulse airflow dryer is 200-300kg/h, the drying temperature is 80-110 ℃, and the air speed is 10-15 m/s.

Compared with the prior art, the invention has the advantages and beneficial effects that:

1. according to the invention, the talcum powder is modified by adopting fatty acid salt, starch, lanolin succinic acid ester sodium sulfonate and triisostearoyl isopropyl titanate, wherein the fatty acid salt can improve the dispersibility and processability of calcite, and hydroxyl of the starch can form hydrogen bonds with paper fibers, so that a bridging network structure can be formed with the fibers, and the bonding performance with the paper fibers is improved; the lanolin succinic acid ester sodium sulfonate contains sulfonic groups, ester groups, hydroxyl groups and other groups, so that the bonding force between paper fibers and calcite can be improved, the dispersibility of the calcite can also be improved, and the decomposed stone powder has more excellent dispersibility when the lanolin succinic acid ester sodium sulfonate is combined with stearate for use; the isopropyl triisostearoyl titanate improves the compatibility of organic matters and inorganic matters, improves the mechanical property of the material, can improve the thixotropic property and adhesive force of a filling system, ensures that the contact degree of ink and the surface of paper is good during printing, and simultaneously can improve the filling amount of calcite in the paper and reduce the cost of the paper.

2. According to the method, the polychlorinated p-xylene and the octavinyl octasilsesquioxane are adopted to carry out secondary modification on the calcite, the polychlorinated p-xylene can form a layer of protective film on the surface of the calcite, the moisture and mildew resistance of the calcite are improved, the polychlorinated p-xylene can be used in combination with the octavinyl octasilsesquioxane, the compatibility of the polychlorinated p-xylene with other materials can be improved, the binding force between the polychlorinated p-xylene and the calcite is improved, and the retention rate of the filler in paper is not reduced.

3. The calcite powder modified by the method can improve the dispersibility and compatibility of the decomposed stone, improve the binding force with fibers, and has excellent moisture-proof and mildew-proof properties, and the method is simple in process and low in cost, and when the calcite powder is used as a papermaking filler, the smoothness and whiteness of the surface of paper can be improved, the retention rate and filling amount of the filler in the paper can be improved, the mechanical properties of the paper can be improved, the moisture-proof and mildew-proof properties of the paper can be improved, and the paper can be completely stored for a long time.

4. The method adopts the pulse airflow dryer to dry the modified calcite powder, so that the drying and heating are uniform, the efficiency is high, the modifier can be better wrapped on the surface of the calcite powder, and the dispersibility of the calcite powder is improved.

Detailed Description

The present invention will be described in further detail with reference to specific embodiments. It should be emphasized that the following description is merely exemplary in nature and is not intended to limit the scope of the invention or its application.