Factors affect the strength of wet water kraft tape!

The main factor affecting the strength of wet water kraft tape is the length of the fiber used in papermaking.
After the raw material is determined, it is actually related to the papermaking process and the chemical composition of the fiber.

 

The effect of beating on fiber, especially the degree of fiber separation and brooming, is the main factor affecting the fiber bonding, because the fiber surface area and the number of hydrogen bonds are related to beating.

 

At the same time, the binding force of the fiber is related to the chemical composition, physical properties and tissue arrangement of the fiber.

 

In other words, the content of lignin, hemicellulose and cellulose of fiber will also affect the combination of fiber to a certain extent.

 

1) Influence of size types

 

Different kinds of pulp are different in physical structure and chemical composition. Generally speaking, chemical wood pulp has the largest fiber adhesion, followed by cotton pulp and mechanical wood pulp.

 

2) Effect of Hemicellulose

 

The pulp with more hemicellulose content is easy to absorb water and swell when beating, which increases the specific surface area and binding area of fiber and improves the fiber binding force.

 

The molecular chain of hemicellulose is shorter than that of cellulose, and it is more hydrophilic. It is easy to absorb water, swell and fine fibrosis when beating. Therefore, the pulp containing more hemicellulose is easier to beating and the binding force between fibers is larger.

 

Of course, the content of hemicellulose is too high, which is not good for beating and papermaking. The main reason is that the moisture absorption and swelling of hemicellulose are too fast, and the beating degree is too high. The wet kraft paper tape is transparent and brittle with low strength.

 

On the other hand, more hemicelluloses and more short fibers will reduce the strength of the fiber itself and reduce the fiber adhesion.

 

3) Effects of cellulose

 

Generally speaking, cellulose molecular chain is long, its degree of polymerization is high, the strength of the fiber itself is large, it is not easy to cut off when beating, so when it is cut to the appropriate length, the fiber has been fully separated and broomed, and the binding force between fibers is also large.

 

4) Effect of lignin

 

As mentioned earlier, lignin is mainly distributed in the outer layer of primary wall and secondary wall of fiber.
Due to the low hydrophilicity of lignin, the existence of lignin affects the swelling and fine fibrosis of fiber.
Therefore, the pulp containing more lignin is not easy to beat and has poor fiber adhesion.

 

5) Effects of paper additives

 

The addition of hydrophilic substances, such as starch, protein, vegetable gum, etc., will increase the binding force between fibers.
This is because these substances have the same polar hydroxyl groups as cellulose.
Because the hydroxyl groups are hydrogen bonded, they are more stable than pure fibers and fibers.

 

Adding hydrophobic substances, such as inorganic fillers and alum, will reduce the binding force between fibers. This is because the addition of these substances will separate the fibers from the fibers and reduce the fiber indirect contact surface, thus affecting the fiber adhesion.

 

6) Influence of papermaking process operation

 

This is the technical content of the work, such as beating, such as drying, because the strength of wet kraft paper tape is not only related to the fiber itself, but also to the bonding strength of the fiber of the wet kraft paper tape, and the bonding strength is related to the operation of the wet kraft paper tape.