CN106948213A - A kind of calcium carbonate high-filling amount fiber and preparation method and application - Google Patents

Abstract

The invention belongs to the technical field of fiber material preparation, and in particular relates to a calcium carbonate high-filling fiber, a preparation method and application thereof. The preparation method comprises the following steps: mixing the pulp with a beating degree of 20-60°SR and calcium chloride solution in a certain proportion, stirring and reacting; adding excess sodium hydroxide solution to the reacted pulp, and continuing to stir and react ; filter the fully reacted pulp, then make a new pulp suspension with water, and pass excessive carbon dioxide gas into the pulp suspension in a suitable environment; after the reaction is complete, wash the pulp with water and then filter to obtain the obtained Calcium Carbonate High Filling Fiber. The calcium carbonate high-filling fiber obtained in the present invention not only reduces the cost of raw materials, but also solves the problem of low retention rate of calcium carbonate added to the fiber in the form of filling, and can also improve the problem of strength reduction of paper due to filling. .

Description

A kind of calcium carbonate high filling fiber and its preparation method and application

technical field

The invention belongs to the technical field of fiber material preparation, and in particular relates to a calcium carbonate high-filling fiber, a preparation method and application thereof.

Background technique

Filling refers to adding water-insoluble or slightly water-soluble white mineral fine fillers to the fiber suspension of paper stock, so that the prepared paper has certain properties that are difficult to possess without filling. Filling not only saves fiber raw materials and reduces the cost of paper, but also improves the optical properties of paper to meet the requirements of some special properties of paper.

As an important inorganic chemical raw material, calcium carbonate is a commonly used filler in paper production, which can improve the opacity and whiteness of paper; but the traditional filling method, with the increase of filler content, will lead to fiber The binding force between fibers and fillers and between fibers and fillers is reduced, thereby reducing the physical strength of the paper such as tensile strength and tearing degree, and the phenomenon of lint and powder falling on the paper. In order to solve the existing problems, it is urgent to find a new way to add calcium carbonate to the fiber.

Contents of the invention

In order to overcome the shortcoming and deficiency of above-mentioned prior art, primary purpose of the present invention is to provide a kind of preparation method of calcium carbonate high loading fiber.

Another object of the present invention is to provide the calcium carbonate high-filling fiber prepared by the above method.

Another object of the present invention is to provide the application of the above calcium carbonate high-filling fiber in the field of papermaking.

The object of the present invention is achieved through the following solutions:

A preparation method of calcium carbonate high filling fiber, comprising the following steps:

(1) Mix the slurry with a beating degree of 20-60 ° SR and calcium chloride solution in a certain proportion, and stir to react;

(2) Add excessive sodium hydroxide solution in the fully reacted pulp in step (1), continue stirring reaction;

(3) Filter the fully reacted pulp in step (2), then make a new pulp suspension with water, and pass excessive carbon dioxide gas into the pulp suspension at a certain temperature; after the reaction is complete, wash the pulp with water Then filter to obtain the required calcium carbonate high-filling fiber.

The volume ratio of the absolute dry mass of the slurry described in step (1) to the calcium chloride solution is 1:50 to 1:100 g/ml.

The molar concentration of the calcium chloride solution described in step (1) is 0.2-0.8 mol/L.

The stirring reaction described in the step (1) refers to reacting for 1-2 hours at a reaction temperature of 40-80° C. and a stirring speed of 200-800 r/min.

The molar concentration of the sodium hydroxide solution described in step (2) is 0.2-0.6 mol/L.

The stirring reaction described in step (2) refers to the reaction at a reaction temperature of 40-80° C. and a stirring speed of 200-800 r/min for 0.5-1 h.

The mass concentration of the pulp suspension described in step (3) is 1-5%.

The temperature described in step (3) is -10°C to 20°C.

A calcium carbonate high-filling fiber prepared by the above-mentioned preparation method has a calcium carbonate filling amount of more than 45%.

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

The present invention adopts the method of in-situ polymerization, first let calcium ions penetrate into the cell cavity of the fiber, then use sodium hydroxide to precipitate calcium ions in the cell cavity to obtain calcium hydroxide, and finally pass carbon dioxide gas into the pulp suspension , so that calcium hydroxide and carbonate combined to generate calcium carbonate, precipitated in the fiber cells. The obtained new calcium carbonate high-filling fiber not only reduces the cost of raw materials, but also solves the problem of low retention rate of calcium carbonate added to the fiber in the form of filling, and can also improve the problem of strength reduction of paper due to filling.

detailed description

The present invention will be further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

All the reagents used in the examples can be purchased from the market.

Embodiment 1: the preparation of calcium carbonate high filling fiber

The beating degree is that the slurry of 20 ° SR is mixed with the calcium chloride solution that the molar concentration is 0.2mol/L according to the absolute dry mass of the slurry and the volume ratio of the calcium chloride solution is 1:100g/ml, in a magnetic stirrer React at a temperature of 40°C and a stirring speed of 200r/min for 1h. After the reaction is complete, add excess sodium hydroxide solution with a molar concentration of 0.2 mol/L to the Erlenmeyer flask, and continue the reaction for 0.5 h under the same conditions. After the reaction is complete, the pulp is filtered. The filtered pulp was made into a pulp suspension with a mass concentration of 1% with tap water, and excess carbon dioxide gas was passed into the pulp suspension with a gas cylinder in an environment of -10°C. Finally, the fully reacted pulp is washed with tap water and then filtered to obtain calcium carbonate high-filling fiber.

Utilize the calcium carbonate high-filling fiber prepared in this embodiment to make paper with a weight of 70 ^g /m2, and the fracture length of the paper measured by the standard method is 2.478 km. However, under the same quantitative and calcium carbonate filling conditions, the fracture length of the paper made by the traditional filling method is 1.79km.

Embodiment 2: the preparation of calcium carbonate high filling fiber

Mix pulp with a beating degree of 30°SR and a calcium chloride solution with a molar concentration of 0.4mol/L at a volume ratio of 1:80g/ml between the absolute dry mass of the slurry and the calcium chloride solution, and place on a magnetic stirrer React at a temperature of 50° C. and a stirring speed of 350 r/min for 1 h. After the reaction is complete, add excess sodium hydroxide solution with a molar concentration of 0.3 mol/L to the Erlenmeyer flask, and continue the reaction for 0.5 h under the same conditions. After the reaction is complete, the pulp is filtered. The filtered pulp was made into a pulp suspension with a mass concentration of 2% with tap water, and excessive carbon dioxide gas was passed into the pulp suspension with a gas cylinder in an environment of 0°C. Finally, the fully reacted pulp is washed with tap water and then filtered to obtain calcium carbonate high-filling fiber.

Utilize the calcium carbonate high-filling fiber prepared in this embodiment to make a calcium carbonate high-filling paper with a weight of 70 g/m ² , and the fracture length of the paper measured by a standard method is 3.428 km. However, under the same quantitative and calcium carbonate filling conditions, the fracture length of the paper made by the traditional filling method is 2.71km.

Embodiment 3: the preparation of calcium carbonate high filling fiber

Mix the pulp with a beating degree of 40°SR and the calcium chloride solution with a molar concentration of 0.5mol/L at a volume ratio of 1:70g/ml between the absolute dry mass of the slurry and the calcium chloride solution, and place on a magnetic stirrer React at a temperature of 60°C and a stirring speed of 500r/min for 1.5h. After the reaction was complete, an excess of sodium hydroxide solution with a molar concentration of 0.4 mol/L was added to the Erlenmeyer flask, and the reaction was continued for 1 h under the same conditions. After the reaction is complete, the pulp is filtered. The filtered pulp was made into a pulp suspension with a mass concentration of 3% with tap water, and excessive carbon dioxide gas was passed into the pulp suspension with a gas cylinder in an environment of 10°C. Finally, the fully reacted pulp is washed with tap water and then filtered to obtain calcium carbonate high-filling fiber.

Utilize the fiber with high calcium carbonate filling content prepared in this example to manufacture paper with a high calcium carbonate filling content of 70 g/m ² , and the fracture length of the paper measured by the standard method is 4.280 km. However, under the same quantitative and calcium carbonate filling conditions, the fracture length of the paper made by the traditional filling method is 3.21km.

Embodiment 4: the preparation of calcium carbonate high filling fiber

Mix the pulp with a beating degree of 60°SR and the calcium chloride solution with a molar concentration of 0.8mol/L according to the volume ratio of the absolute dry mass of the slurry to the calcium chloride solution at 1:50g/ml, and place on a magnetic stirrer React at a temperature of 80°C and a stirring speed of 800r/min for 2h. After the reaction was complete, an excess of sodium hydroxide solution with a molar concentration of 0.6 mol/L was added to the conical flask, and the reaction was continued for 1 h under the same conditions. After the reaction is complete, the pulp is filtered. The filtered pulp was made into a pulp suspension with a mass concentration of 5% with tap water, and excessive carbon dioxide gas was passed into the pulp suspension with a gas cylinder in an environment of 20°C. Finally, the fully reacted pulp is washed with tap water and then filtered to obtain calcium carbonate high-filling fiber.

Utilize the calcium carbonate high-filling fiber prepared in this embodiment to make paper with a weight of 70 g/m ² , and the fracture length of the paper measured by the standard method is 4.820 km. However, under the same quantitative and calcium carbonate filling conditions, the fracture length of the paper made by the traditional filling method is 3.79km.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (10)

1. a kind of preparation method of calcium carbonate high-filling amount fiber, it is characterised in that comprise the following steps：

(1) beating degree is mixed by a certain percentage for 20~60 ° of SR slurry with calcium chloride solution, stirring reaction；

(2) excessive sodium hydroxide solution is added in the complete paper pulp of reaction into step (1), continues stirring reaction；

(3) by the complete paper pulp filtering of reaction in step (2), new pulp suspension is then made into water, in certain temperature It is lower that excessive carbon dioxide is passed through into pulp suspension；After reaction completely, refilter, produce after paper pulp is washed with water The calcium carbonate high-filling amount fiber.

2. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (1) Described in slurry absolute dry mass and calcium chloride solution volume ratio be 1:50~1:100g/ml.

3. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (1) Described in calcium chloride solution molar concentration be 0.2~0.8mol/L.

4. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (1) Described in stirring reaction refer under 40~80 DEG C of reaction temperature, 200~800r/min mixing speed react 1~2h.

5. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (2) Described in sodium hydroxide solution molar concentration be 0.2~0.6mol/L.

6. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (2) Described in stirring reaction refer under 40~80 DEG C of reaction temperature, 200~800r/min mixing speed reaction 0.5~ 1h。

7. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (3) Described in pulp suspension mass concentration be 1~5%.

8. a kind of preparation method of calcium carbonate high-filling amount fiber according to claim 1, it is characterised in that step (3) Described in temperature be -10 DEG C~20 DEG C.

9. a kind of calcium carbonate high-filling amount fiber, it is characterised in that it is as a kind of carbonic acid described in any one of claim 1 to 8 The preparation method of calcium high-filling amount fiber is prepared, and the amount of being filled with of its calcium carbonate reaches more than 45%.

10. a kind of calcium carbonate high-filling amount fiber as claimed in claim 9 is in the application of field of papermaking.