1. Overview
Methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) are non-ionic cellulose ethers made from the natural polymer material - cellulose through a series of chemical processing. Methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) are odorless, tasteless, non-toxic self-colored powders that can be dissolved in cold water to form a transparent viscous solution. They have the properties of thickening, bonding, dispersion, emulsification, film-forming, suspension, adsorption, gelling, surface activity, moisture retention and protective colloid.
Methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) can be used in building materials, coatings, synthetic resins, ceramics, medicine, food, textiles, agriculture, cosmetics and tobacco industries.
Product specifications and classifications The products are divided into cold water soluble type S and ordinary type .
Common specifications of hydroxypropyl methylcellulose
| product | MC | HPMC |
| HE | HF | HJ | HK |
| Methoxy | content(%) | 27.0~32.0 | 28.0~30.0 | 27.0~30.0 | 16.5~20.0 | 19.0~24.0 |
| Degree of substitution DS | 1.7~1.9 | 1.7~1.9 | 1.8~2.0 | 1.1~1.6 | 1.1~1.6 |
| Hydroxypropoxy | content(%) |
| 7.0~12.0 | 4~7.5 | 23.0~32.0 | 4.0~12.0 |
| Degree of substitution DS |
| 0.1~0.2 | 0.2~0.3 | 0.7~1.0 | 0.1~0.3 |
| Water content (Wt%) | ≤5.0 |
| Ash content (Wt%) | ≤1.0 |
| pH | 5.0~8.5 |
| Exterior | Milky white granular powder or white granular powder |
| Fineness | 80 mesh |
| Viscosity (mPa.s) | See viscosity specifications |
Viscosity Specifications
| Specification | Viscosity range (mpa.s) | Specification | Viscosity range (mpa.s) |
| 5 | 3~9 | 8000 | 7000~9000 |
| 15 | 10~20 | 10000 | 9000~11000 |
| 25 | 20~30 | 20000 | 15000~25000 |
| 50 | 40~60 | 40000 | 35000~45000 |
| 100 | 80~120 | 60000 | 46000~65000 |
| 400 | 300~500 | 80000 | 66000~84000 |
| 800 | 700~900 | 100000 | 85000~120000 |
| 1500 | 1200~2000 | 150000 | 130000~180000 |
| 4000 | 3500~4500 | 200000 | ≥180000 |
*NDJ-4 rotational viscometer, 2% aqueous solution, 20°C
3. Product properties
Properties: This product is a white or off-white powder, odorless, tasteless and non-toxic.
Water solubility and thickening ability: This product can be dissolved in cold water to form a transparent viscous solution.
Solubility in organic solvents: Because it contains a certain amount of hydrophobic methoxy groups, this product can be dissolved in some organic solvents, and can also be dissolved in solvents mixed with water and organic matter.
Salt resistance: Since this product is a non-ionic polymer, it is relatively stable in aqueous solutions of metal salts or organic electrolytes.
Surface activity: The aqueous solution of this product has surface activity and has the functions and properties of emulsification, protective colloid and relative stability.
Thermal gelation: When the aqueous solution of this product is heated to a certain temperature, it becomes opaque until a (poly)flocculated state is generated, causing the solution to lose viscosity. However, it will return to the original solution state after cooling. The temperature at which the gelation phenomenon occurs depends on the type of product, the concentration of the solution and the heating rate.
PH stability: The viscosity of the aqueous solution of this product is stable within the range of PH3.0-11.0.
Water retention effect: Since this product is hydrophilic, it can maintain high water retention in the product when added to mortar, gypsum, paint, etc.
Shape retention: Compared with other water-soluble polymers, the aqueous solution of this product has special viscoelastic properties. Its addition has the ability to keep the shape of extruded ceramic products unchanged.
Lubricity: Adding this product can reduce the friction coefficient and improve the lubricity of extruded ceramic products and cement products.
Film-forming property: This product can generate flexible, transparent, and mechanically excellent films with good oil and fat resistance.
4. Physical and chemical properties
Particle size: 100 mesh pass rate is greater than 98.5%, 80 mesh pass rate is 100%
Carbonization temperature: 280~300℃
Apparent density: 0.25~0.70/cm Specific gravity 1.26~1.31
Color change temperature: 190~200℃
Surface tension: 2% aqueous solution is 42~56dyn/cm
Solubility: Soluble in water and some solvents, the aqueous solution has surface activity. High transparency. Stable performance, solubility changes with viscosity, the lower the viscosity, the greater the solubility.
HPMC also has thickening ability, salt resistance, pH stability, water retention, dimensional stability, excellent film-forming properties, as well as a wide range of enzyme resistance, dispersibility and adhesion.
V. Main uses
The main use of industrial grade HPMC is as a dispersant in the production of polyvinyl chloride, and it is the main auxiliary agent for the preparation of PVC by suspension polymerization. In addition, it is used as a thickener, stabilizer, emulsifier, excipient, water retention agent, film-forming agent, etc. in the production of other petrochemical, coatings, building materials, paint removers, agricultural chemicals, inks, textile printing and dyeing, ceramics, papermaking, cosmetics and other products. In the application of synthetic resins, the obtained products can have the characteristics of regular particles, looseness, appropriate apparent specific gravity, and excellent processing performance, thus basically replacing gelatin and polyvinyl alcohol as dispersants.
VI. Packaging:
Industrial grade: Double-layer bag:
Inner polyethylene film bag, outer composite paper bag, net weight of each bag is 20/25 kg.
Medical and food grade: Paper barrel packaging:
Outer composite paper barrel, inner polyethylene film bag, net weight of each barrel is 10/20 kg.