CN112430860A

CN112430860A - Preparation method of aramid fibrid and aramid fibrid

Info

Publication number: CN112430860A
Application number: CN202011294447.6A
Authority: CN
Inventors: 李永锋; 常小斌; 熊贤仲
Original assignee: Ganzhou Longbang Material Technology Co ltd
Current assignee: Ganzhou Longbang Material Technology Co ltd
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2021-03-02
Also published as: WO2022105312A1

Abstract

According to the preparation method of the aramid fibrid, the aramid polymer is placed in a hot gas pipeline to form floccules, the floccules are mixed with water and subjected to beating treatment to form the aramid fibrid, the fibrid prepared by the method is fibrous and silk-film, the binding capacity of finished paper is strong, the bonding performance of paper sheets is excellent, the insulating property is good, and the prepared paper sheets are particularly suitable for the insulating field. In addition, the preparation method of the aramid fibrid provided by the invention has the advantages of easily available raw materials, low cost and simple process, and is suitable for industrial production.

Description

Preparation method of aramid fibrid and aramid fibrid

Technical Field

The invention belongs to the technical field of manufacturing of synthetic fibers, and particularly relates to an aramid fibrid and a preparation method thereof.

Background

Aramid fibrids refer to synthetic polymers having a fibrous structure. Also known as fibrids. The main varieties include polycaprolactam, polyester, polyacrylonitrile, aromatic polyamide and the like. The product has a form such as branch tip, a length of about 1mm, and a binding property, and can be made into synthetic paper or thin nonwoven fabric by binding chemical fiber after being mixed into slurry.

However, the aramid fibrids obtained by the methods for preparing aramid fibrids described in the prior documents are usually solidified and formed in a solidifying liquid, and the binding capacity of the formed paper is poor.

How to provide a novel preparation method of aramid fibrids is a technical problem which is urgently needed to be solved in the prior art.

Disclosure of Invention

In view of this, it is necessary to provide a method for preparing aramid fibrids with strong binding ability of paper, excellent bonding property of paper sheet, and good insulating property.

In order to solve the problems, the invention adopts the following technical scheme:

the preparation method of the aramid fibrid comprises the following steps:

placing an aramid polymer in a hot gas line to form a floe;

and mixing the floccule with water, and pulping to form aramid fibrid.

In some of these embodiments, the aramid polymer has a solids content of 10-20% and a temperature of 60-120 degrees.

In some of these embodiments, the hot gas duct is a vertically oriented duct having a diameter of 20mm to 100mm and a length of 100mm to 2000 mm.

In some embodiments, the step of placing the aramid polymer in a hot gas pipeline to form the floccule specifically comprises the steps of:

after the aramid polymer is sprayed into the hot gas pipeline through a spinning nozzle, a solvent in the aramid polymer is instantaneously evaporated, the solvent moves upwards along with hot gas, and floccules of the aramid polymer after the solvent is evaporated sink downwards.

In some of these embodiments, the spinneret is a spinning spinneret with a number of 500-5000 holes and a diameter of 0.06-0.20 mm.

In some of these embodiments, the hot gas is nitrogen and the temperature of the hot gas is 150 to 250 degrees.

In some of these embodiments, the following steps are also included:

and washing the aramid fiber fibrid.

In some of these embodiments, the washing is accomplished with a water wash apparatus for the pulp, which includes a belt washer or a drum washer.

In addition, the invention also provides aramid fibrid, which is prepared by the preparation method of the aramid fibrid.

Compared with the prior art, the preparation method of the aramid fibrid provided by the application places the aramid polymer in a hot gas pipeline to form floccule, mixes the floccule with water, and carries out beating treatment to form the aramid fibrid.

In addition, the preparation method of the aramid fibrid provided by the invention has the advantages of easily available raw materials, low cost and simple process, and is suitable for industrial production.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention or in the description of the prior art will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a flow chart of steps of a method for preparing aramid fibrids according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "horizontal", "inside", "outside", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments.

Referring to fig. 1, the preparation method of the aramid fibrid provided by the present application includes the following steps:

step S110: the aramid polymer is placed in a hot gas line to form a floe.

Specifically, in the step of placing the aramid polymer in a hot gas pipeline to form a floccule, the following steps are specifically included:

Further, the solid content of the aramid polymer is 10-20%, and the temperature is 60-120 ℃.

It can be understood that when the aramid polymer satisfies the above parameters, the aramid fibrid paper prepared therefrom has stronger binding ability and more excellent bonding property to paper sheets.

Furthermore, the hot gas pipeline is a pipeline in the vertical direction, the diameter of the hot gas pipeline is 20mm-100mm, and the length of the hot gas pipeline is 100mm-2000 mm.

It can be understood that when the hot gas pipeline and the spinneret meet the above parameters, the aramid fibrid prepared by the aramid fibrid is fibrous and silk film-shaped, the aramid fibrid prepared by the aramid fibrid is longer, and the hairiness is more abundant.

Step 120: and mixing the floccule with water, and pulping to form aramid fibrid.

Further, the preparation method of the aramid fibrid further comprises the step of washing the aramid fibrid.

In particular, the washing is done with a washing apparatus for pulp, which comprises a belt washer or a drum washer.

The fibrid prepared by the method is in fibrous and silk film shapes, the binding capacity of the formed paper is strong, the bonding performance of the paper is excellent, the insulating property is good, and the prepared paper is particularly suitable for the insulating field.

The technical solution of the present invention will be described in detail with reference to the following detailed examples.

Example 1:

the polymer had a solids content of 16.8 and a viscosity of 1.93 as described above. The hot nitrogen line was 200 ℃ with a diameter of 50mm and a length of 1500 mm. The polymer is sprayed into hot nitrogen through a spinning nozzle with the hole number of 5000 and the hole diameter of 0.18mm, and the flocculent fibers collected by the method are sunk to the lower part, and are subjected to beating treatment and washing and cleaning procedures to form a product, the mechanical beating degree of the product is 36SR, the fiber shape is very wide and fibrous and silk film shapes under the observation of a fiberscope, and the forming is good. The mixed liquid is further disc-milled by a special disc mill, the membrane of the precipitated fiber is further stretched, and the beating degree reaches 50 SR.

And (3) mixing the fibrids and the chopped fibers according to the weight ratio of 1: 1, the aramid fiber insulation paper sheet is made in a paper machine, and the formed paper sheet is processed at high temperature and high pressure, the thickness of the paper sheet is 0.05mm, and the electrical strength of the paper sheet is as follows: 19.7kv/mm, which is far higher than the level of domestic like products; also reach the international leading level;

example 2:

the polymer had a solids content of 13.8 and a viscosity of 2.2 according to the above procedure. The hot nitrogen pipeline has the temperature of 190 ℃, the diameter of 60mm and the length of 2000 mm. The polymer is sprayed into hot nitrogen through a spinneret with 3000 holes and 0.15mm diameter, and the flocculent fiber is deposited to the lower part, and the product is formed through beating, washing and cleaning, and has mechanical beating degree of 42SR, wide fiber shape and silk film shape under fiberscope observation. The mixed liquid is further disc-milled by a special disc mill, the membrane of the precipitated fiber is further stretched, and the beating degree reaches 67 SR.

And (3) mixing the fibrids and the chopped fibers according to the weight ratio of 1: 1, the aramid fiber insulation paper sheet is made in a paper machine, and the formed paper sheet is processed at high temperature and high pressure, the thickness of the paper sheet is 0.05mm, and the electrical strength of the paper sheet is as follows: 20.8kv/mm, which is far higher than the level of domestic like products; also reach the international leading level;

example 3:

the polymer had a solids content of 20.8 and a viscosity of 1.33 as described above. The hot nitrogen line was 200 ℃ with a diameter of 50mm and a length of 1000 mm. The polymer is sprayed into hot nitrogen through a spinning nozzle with the hole number of 5000 and the hole diameter of 0.18mm, and the flocculent fibers collected by the method are sunk to the lower part, and are subjected to beating treatment and washing and cleaning procedures to form a product, the mechanical beating degree of the product is 29SR, the fiber shape is very wide and fibrous and silk film shapes under the observation of a fiberscope, and the forming is good. The mixed liquid is further disc-milled by a special disc mill, the membrane of the precipitated fiber is further stretched, and the beating degree reaches 42 SR.

And (3) mixing the fibrids and the chopped fibers according to the weight ratio of 1: 1, the aramid fiber insulation paper sheet is made in a paper machine, and the formed paper sheet is processed at high temperature and high pressure, the thickness of the paper sheet is 0.05mm, and the electrical strength of the paper sheet is as follows: 17.8kv/mm, which is far higher than the level of domestic like products; also reaches the international leading level.

The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. The preparation method of the aramid fibrid is characterized by comprising the following steps:

placing an aramid polymer in a hot gas line to form a floe;

and mixing the floccule with water, and pulping to form aramid fibrid.

2. The preparation method of the aramid fibrid as claimed in claim 1, wherein the solid content of the aramid polymer is 10-20% and the temperature is 60-120 ℃.

3. The method for preparing aramid fibrids according to claim 1, wherein the hot gas pipeline is a vertical pipeline with a diameter of 20mm to 100mm and a length of 100mm to 2000 mm.

4. The method for preparing aramid fibrids according to claim 3, wherein the step of placing the aramid polymer in a hot gas pipeline to form floes comprises the following steps:

5. The method for preparing aramid fibrids as claimed in claim 4, wherein the spinneret is a spinning spinneret with a number of 500-5000 holes and a diameter of 0.06-0.20 mm.

6. The method for preparing aramid fibrids according to claim 4, wherein the hot gas is nitrogen, and the temperature of the hot gas is 150-250 ℃.

7. The method for preparing the aramid fibrids as claimed in claim 1, further comprising the steps of:

and washing the aramid fiber fibrid.

8. The method for preparing aramid fibrids according to claim 1, wherein the washing is performed with a pulp washing apparatus comprising a belt washer or a drum washer.

9. An aramid fibrid characterized by being prepared by the method for preparing an aramid fibrid as claimed in any one of claims 1 to 8.