(New) HPMC 18 questions

Shandong chuangyao Biotechnology Co., Ltd. summarizes the core issues of HPMC.

What are the main uses of HPMC?

HPMC is widely used in building materials, coatings, synthetic resins, ceramics, medicine, food, textile, agriculture, cosmetics, tobacco and other industries. HPMC can be divided into industrial grade, food grade and medical grade according to its use.

2 hydroxypropylmethylcellulose can be divided into several kinds. What is the difference in its use?

HPMC can be divided into instant type (brand suffix "s") and hot-soluble type. Instant products disperse rapidly in cold water and disappear in water. At this time, the liquid has no viscosity, because HPMC is only dispersed in water and has no real dissolution. About 2 minutes later, the viscosity of the liquid gradually increased, forming a transparent white sticky colloid. Heat soluble products can be dispersed in cold water and disperse rapidly in hot water, and disappear in hot water. When the temperature drops to a certain temperature (according to the gel temperature of the product), the viscosity slowly appears until the transparent colloid colloid is formed.

How to judge the quality of HPMC simply and intuitively?

1) Although whiteness and whiteness can not determine whether HPMC is easy to use, and if a whitening agent is added in the production process, its quality will be affected, but most good products have good whiteness.

2) Fineness: the fineness of HPMC is generally 80 mesh and 100 mesh, 120 mesh is less, the finer the better.

3) Transparence: when HPMC is put into water and a transparent colloid is formed, its transparence can be seen. The greater the transparence, the better the transparence. It means that there are less insoluble substances in it. The transparence of vertical reactor is generally good and that of horizontal reactor is poor. However, it cannot be said that the quality of vertical reactor is better than that of horizontal reactor. There are many factors determining the product quality.

4) Specific gravity: the larger the specific gravity is, the heavier it is, the greater the specific gravity is. Generally, the higher the content of hydroxypropyl is, the better the water retention is.

What are the dissolution methods of 4-hydroxypropylmethylcellulose?

1) All models can be added to the material by dry mixing method;

2) When it needs to be added directly to the normal temperature aqueous solution, it is better to use the cold water dispersion type, and the thickening can be generally carried out within 10-90 minutes after adding (stirring and stirring)

3) Common models are first dispersed by hot water, then cooled by cold water;

4) When dissolving, if caking and wrapping occurs, it is due to insufficient mixing or the common model is directly added to the cold water. At this time, it should be quickly stirred.

5) If bubbles are produced during dissolution, they can be removed by standing for 2-12 hours (the specific time depends on the consistency of the solution), vacuuming, pressurizing and other methods, or adding a proper amount of defoamer.

5 hydroxypropylmethylcellulose in putty powder?

The amount of HPMC used in practical application depends on the climate, temperature, local ash calcium quality, putty powder formula and the quality required by customers, but there are differences in different places, generally speaking, between 4-5 kg.

What is the proper viscosity of 6-hydroxypropylmethylcellulose?

The putty powder is usually 100000 yuan, and the mortar with higher requirements needs 150000 yuan to be easy to use. Moreover, the important role of HPMC is water conservation, followed by thickening. In putty powder, as long as the water retention is good and the viscosity is lower (7-8), it is also OK. Of course, the viscosity is higher and the relative water retention is better. When the viscosity exceeds 100000, the effect of viscosity on the water retention is not significant.

What are the main raw materials of HPMC?

Main raw materials of HPMC: refined cotton, methyl chloride, propylene oxide, and other raw materials, such as flake alkali, toluene acid.

8 hydroxypropylmethylcellulose in putty powder application, what is the main role, whether chemistry?

Among putty powder, it has three functions: thickening, water conservation and construction. Thickening, cellulose can be thickened to play a role of suspension, to keep the solution uniform up and down, anti sagging. Water retention: make putty powder dry slowly, assist the reaction of grey calcium under the action of water. Construction: cellulose has lubricating effect, which can make putty powder have good workability. HPMC is not involved in any chemical reaction, but only plays an auxiliary role.

Hydroxypropylmethylcellulose is a non-ionic cellulose ether, so what is non-ionic?

Generally speaking, inert substances do not participate in chemical reactions.

CMC (carboxymethylcellulose) belongs to cationic cellulose, so it will become tofu dregs when encountering grey calcium.

What are the main technical specifications of HPMC?

Hydroxypropyl content

Methyl content

viscosity

Ash content

Drying weightlessness

What is the gel temperature of 11 hydroxypropyl methylcellulose?

The gel temperature of HPMC is related to its methoxy content. The lower the methoxy content, the higher the gel temperature.

Is there any relationship between hydroxypropylmethylcellulose and putty powder?

It matters!!! It is the poor water retention of HPMC, which will cause powder loss.

13 hydroxypropylmethylcellulose in putty powder application, putty powder bubble what reason?

In putty powder, HPMC has three functions of thickening, water retention and construction, and the causes of bubbles are as follows:

1. Too much water is added.

2. If the bottom layer is not dry, scratch another layer on it, and it is easy to blister.

What's the difference between the cold water instant and hot-soluble type of 14 hydroxypropylmethylcellulose in the production process?

The cold water instant type of HPMC is treated with glyoxal, which can be quickly dispersed in cold water, but it is not really dissolved. When the viscosity is up, it is dissolved. The heat-soluble type is not treated with glyoxal. If glyoxal is released in large quantity, it will disperse quickly, but the viscosity will be slow