Cellulose ether is a non-ionic semi-synthetic high molecular polymer, which is water-soluble and solvent-soluble. It has different effects in different industries. For example, in chemical building materials, it has the following composite effects:

①?Water retaining agent, ②Thickener, ③Leveling property, ④Film forming property,

⑤Binder

In the polyvinyl chloride industry, it is an emulsifier and dispersant; in the pharmaceutical industry, it is a binder and a slow and controlled release framework material, etc. Because cellulose has a variety of composite effects, its application The field is also the most extensive. Next, I will focus on the use and function of cellulose ether in various building materials.

In latex paint

In the latex paint industry, to choose hydroxyethyl cellulose, the general specification of equal viscosity is 30000-50000cps, which corresponds to the specification of HBR250, and the reference dosage is generally about 1.5‰-2‰. The main function of hydroxyethyl in latex paint is to thicken, prevent the gelation of the pigment, help the dispersion of the pigment, the stability of the latex, and increase the viscosity of the components, which is helpful for the leveling performance of the construction: Hydroxyethyl cellulose is more convenient to use. It can be dissolved in cold water or hot water, and it is not affected by the pH value. It can be used safely between PI value 2 and 12. The methods of use are as follows:

1. Add directly in production

this method, hydroxyethyl cellulose delayed type should be selected, and the hydroxyethyl cellulose with a dissolution time of more than 30 minutes is used. The steps are as follows: ① Put a certain amount of pure water in a container equipped with a high-shear agitator ② Start stirring continuously at low speed, and at the same time slowly add the hydroxyethyl group into the solution evenly ③Continue to stir until all the granular materials are soaked ④Add other additives and basic additives, etc. ⑤Stir until all the hydroxyethyl groups are completely dissolved, then add other components in the formula and grind until the finished product.

2. Equipped with mother liquor for later use

This method can choose instant type, and has anti-mildew effect cellulose. The advantage of this method is that it has greater flexibility and can be directly added to latex paint. The preparation method is the same as the steps ①-④.

3. Make it into porridge for later use

Since organic solvents are poor solvents (insoluble) for hydroxyethyl, these solvents can be used to formulate porridge. The most commonly used organic solvents are organic liquids in latex paint formulations, such as ethylene glycol, propylene glycol, and film-forming agents (such as diethylene glycol butyl acetate). The porridge hydroxyethyl cellulose can be directly added to the paint. Continue to stir until completely dissolved.

In putty

At present, in most cities in my country, the water-resistant and scrub-resistant environment-friendly putty has been basically valued by people. It is produced by acetal reaction of vinyl alcohol and formaldehyde. Therefore, this material is gradually eliminated by people, and the cellulose ether series products are used to replace this material. That is to say, for the development of environmentally friendly building materials, cellulose is currently the only material.

In the water-resistant putty, it is divided into two types: dry powder putty and putty paste. Among these two kinds of putty, methyl cellulose and hydroxypropyl methyl should be selected. The viscosity specification is generally between 40000-75000cps. The main functions of cellulose are water retention, bonding and lubrication.

Since the putty formulas of various manufacturers are different, some are gray calcium, light calcium, white cement, etc., and some are gypsum powder, gray calcium, light calcium, etc., so the specifications, viscosity and infiltration amount of cellulose selected by the two formulas are also different. The amount added is about 2‰-3‰.