HPMC formulation in building and paint

Hydroxypropyl methylcellulose (HPMC for short) is an important mixed ether, which is a non-ionic water-soluble polymer, and is widely used in food, medicine, daily chemical industry, coating, polymerization reaction and construction as a dispersion suspension , thickening, emulsifying, stabilizing and adhesives, etc., and there is a large gap in the domestic market.

 

Because HPMC has excellent properties such as thickening, emulsification, film forming, protective colloid, moisture retention, adhesion, enzyme resistance and metabolic inertness, it is widely used in coatings, polymerization reactions, building materials, oil production, textiles, food, medicine, Daily-use ceramics, electronic devices and agricultural seeds and other departments.

 

Building materials

 

In building materials, HPMC or MC is usually added to cement, mortar, and mortar to improve construction and water retention properties.

 

HPMC can be used on:

1). Adhesive and caulking agent for gypsum-based adhesive tape;

2). Bonding of cement-based bricks, tiles and foundations;

3). Plasterboard-based stucco;

4). Cement-based structural plaster;

5). In the formula of paint and paint remover.

Adhesive for ceramic tiles

HPMC 15.3 parts

Perlite 19.1 parts

Fatty amides and cyclic thio compounds 2.0 parts

Clay 95.4 parts

Silica seasoning (22μ) 420 parts

450.4 parts of water

Used in cement bonded with inorganic bricks, tiles, stones or cement:

HPMC (degree of dispersion 1.3) 0.3 parts

Cattelan cement 100 parts

Silica sand 50 parts

50 parts of water

Used as a high-strength cement building material additive:

Cattelan cement 100 parts

Asbestos 5 parts

Polyvinyl alcohol repair 1 part

Calcium silicate 15 parts

Clay 0.5 parts

32 parts of water

HPMC 0.8 parts

Paint industry

In the paint industry, HPMC is mostly used in latex paint and water-soluble resin paint components as a film-forming agent, thickener, emulsifier and stabilizer.

Suspension Polymerization of PVC

The field with the largest consumption of HPMC products in my country is the suspension polymerization of vinyl chloride. In the suspension polymerization of vinyl chloride, the dispersion system directly affects the quality of the product PVC resin and its processing and products; it can improve the thermal stability of the resin and control the particle size distribution (that is, adjust the density of PVC). The amount of HPMC accounts for 0.025%~0.03% of the PVC output .

The PVC resin prepared by high-quality HPMC, in addition to ensuring that the performance meets the national standard, also has good physical properties, excellent particle characteristics and excellent melt rheological behavior.

Other industry

Other industries mainly include cosmetics, oil production, detergents, household ceramics and other industries.

Water soluble

HPMC is one of the water-soluble polymers, and its water solubility is related to the content of methoxyl group. When the content of methoxyl group is low, it can be dissolved in strong alkali and has no thermodynamic gelation point. With the increase of methoxyl content, it is more sensitive to water swelling and soluble in dilute alkali and weak alkali. When the methoxyl content is >38C, it can be dissolved in water, and can also be dissolved in halogenated hydrocarbons. If periodic acid is added to HPMC, HPMC will quickly disperse in water without producing insoluble caking substances. This is mainly due to the fact that periodic acid has dihydroxyl groups in the ortho position on the dispersed glycogen.


Post time: Dec-07-2022