Hydroxyethyl Cellulose

The chemical formula (C2H6O2) n

It is a kind of white or yellowish, odorless, non-toxic fibrous or powdery solid. It is prepared by etherification reaction of alkaline cellulose and ethylene oxide (or chloroethanol). It belongs to non-ionic soluble cellulose ether class.Because HEC has good thickening, suspension, dispersion, emulsification, bonding, film forming, water protection and providing protective colloid and other characteristics, has been widely used in oil exploitation, paint, construction, medicine, food, textile, paper making and polymer polymerization and other fields.40 mesh screening rate ≥99%.

English name: HEC, Hydroxyethyl Cellulose

CAS: 9004-62-0

MDL: MFCD00072770

The physical and chemical properties

9004-62-0 formula

Formula:

Molecular formula: C2H6O2· X

Melting point: 288-290℃ (Dec.)

Density: 0.75g /mL at 25℃ (lit.)

Softening temperature: 135-140℃

Expression density: 0.35-0.61g/ml

Decomposition temperature: 205-210℃;It burns more slowly

Balance temperature content: 23℃;50% RH at 6%,84% RH at 29%

Solubility: H2O: ≤5 wt. % at 20℃ Solubility: H2O: ≤5 wt. % at 20℃Insoluble in common organic solvents.It has the properties of thickening, suspending, bonding, emulsifying, dispersing and retaining moisture.Solutions with different viscosity ranges can be prepared.Exceptionally good salt solubility to electrolytes.

Form: powder

Merck: 4673

Appearance: white to light yellow fibrous or powdery solid, non-toxic, tasteless, easily soluble in water.Insoluble in common organic solvents.

Viscosity changes little in the pH range of 2-12, but decreases beyond this range.It has the properties of thickening, suspending, bonding, emulsifying, dispersing, retaining moisture and protecting colloid.Solutions with different viscosity ranges can be prepared.Unstable under normal temperature and pressure, avoid humidity, heat, high temperature, with abnormal good salt solubility to the dielectric, its aqueous solution is allowed to contain high concentration of salt and stable.

Commonly used indicators

Molar degree of substitution (m.S) : 1.8-2.0

Moisture (%) : ≤10

Water insoluble matter (%) : ≤0.5

PH: 6.0 to 8.5

Heavy metal (ug/g) : ≤20

Ash content (%) : ≤5

Viscosity (Mpa. S) 2%

20℃ aqueous solution: 5-60000

Lead (%) : ≤0.001

Application field

Used as adhesives, surfactants, colloidal protectors, dispersants, emulsifiers and dispersion stabilizers.It is widely used in paint, ink, fiber, dyeing, paper making, cosmetics, pesticide, mineral processing, oil recovery and medicine and other fields.

1, generally used as thickening agent, protective agent, adhesive, stabilizer and preparation of emulsion, jelly, ointment, lotion, eye cleaning agent, suppository and tablet additives, also used as hydrophilic gels, skeleton material, skeleton type sustained release preparation, can also be used for food stabilizer and other functions.

2, used in the textile industry sizing agent, electronic and light industry sector bonding, thickening, emulsification, stability and other additives.

3. Used as thickener and fluid loss reducer for water-based drilling fluid and completion fluid, it has obvious thickening effect in brine drilling fluid.It can also be used as fluid loss reducer for oil well cement.It can be cross-linked with polyvalent metal ions to form a gel.

4, this product is used for fracturing method to exploit oil water-based gel fracturing fluid, polystyrene and polyvinyl chloride polymerization of dispersant.It can also be used as emulsion thickening agent in paint industry, humidity sensitive resistance in electronics industry, cement coagulant and water retention agent in construction industry.Ceramic industry glazing and toothpaste adhesive.It is also widely used in printing and dyeing, textile, paper making, medicine, hygiene, food, cigarette, pesticide and fire extinguishing agent, etc.

5, as a surfactant, colloidal protective agent, vinyl chloride, vinyl acetate and other emulsion to take the combination of emulsion stabilizer, and latex viscosity, dispersant, dispersion stabilizer.Widely used in coating, fiber, dyeing, paper, cosmetics, medicine, pesticide and other aspects.It also has many uses in the oil mining and machinery industry.

6. Hydroxyethyl cellulose has surface activity, thickening, suspension, adhesion, emulsification, film formation, dispersion, water retention and protection in pharmaceutical solid and liquid preparations.

7. Dispersant for the polymerization of oil-based gel fracturing fluid, polyvinyl chloride and polystyrene.It can also be used as emulsion thickening agent in paint industry, cement coagulant and water retention agent in construction industry, glaze agent and toothpaste adhesive in ceramic industry.It is also widely used in printing and dyeing, textile, paper making, medicine, hygiene, food, cigarette and pesticide industries.

Product performance

1, HEC can be dissolved in hot water or cold water, high temperature or boiling does not precipitate, so that it has a wide range of solubility and viscosity characteristics, and non-thermal gel;

2, its non-ionic type can coexist with a wide range of other water-soluble polymers, surfactants, salts, is an excellent colloid thickening agent containing high concentration of dielectric solution;

3, water retention capacity is twice higher than methyl cellulose, with good flow regulation;

4. Compared with the recognized methyl cellulose and hydroxypropyl methyl cellulose, the dispersion ability of HEC is the worst, but the protective colloid ability is the strongest.

Method of use

It's added directly to production

1.Pour clean water into a large drum with a high-cut blender.

2.Start stirring at low speed and slowly sift the hydroxyethyl cellulose evenly into the solution.

3.Continue stirring until all particles are soaked.

4.Then add anti-mildew agent, alkaline additives such as pigments, disperse additives, ammonia.

5.Stir until all hydroxyethyl cellulose is completely dissolved (solution viscosity increases significantly) before adding other components in the recipe, and grind until finished product.

Equipped with mother liquor for use

This method is first equipped with a higher concentration of mother liquor, and then join the latex paint.This method has the advantage of greater flexibility, can be directly added to the finished paint, but should be properly stored.The steps are similar to steps 1-4 in method 1, except that there is no need to stir until the solution is completely dissolved into a viscous solution.

With congee - like phenology

Since organic solvents are undesirable for hydroxyethyl cellulose, they can be used to prepare porridge.The most common organic solvents are organic liquids such as ethylene glycol, propylene glycol and film forming agents such as ethylene glycol or diethylene glycol butyl acetate in paint formulations.Ice water is also a bad solvent, so it is often used in conjunction with organic liquids to prepare porridge.Porridge-like hydroxyethyl cellulose can be directly added to the lacquer. In the porridge-like hydroxyethyl cellulose has been dissolved in the liquid.When added to the paint, it dissolves immediately and has a thickening effect.Stir until the hydroxyethyl cellulose is completely dissolved and evenly mixed.General porridge is six parts of organic solvent or ice water mixed with one part of hydroxyethyl cellulose, about 6-30 minutes later, hydroxyethyl cellulose will hydrolyze and significantly increased.In summer, the general water temperature is too high, should not be equipped with porridge.

Use attention

Since surface treated hydroxyethyl cellulose is either a powder or a cellulose solid, it is easily handled and soluble in water, provided that the following considerations are taken into account.

1. Before and after the addition of hydroxyethyl cellulose, it must be constantly stirred until the solution is completely transparent and clear.

2, must slowly sieve into the mixing drum, do not a large number of or has formed a block and spherical hydroxyethyl cellulose directly into the mixing drum.

3, the water temperature and the pH value of the water has an obvious relationship with the dissolution of hydroxyethyl cellulose, special attention must be paid to.

4, do not add some alkaline substances in the mixture before the hydroxyethyl cellulose powder is thoroughly water temperature.Raising the pH value only after the temperature is permeable will help the solution.

5, as far as possible, early to add anti-mildew agent.

6, when using high viscosity type hydroxyethyl cellulose, the concentration of mother liquor should not be higher than 2.5-3%, otherwise the mother liquor is difficult to operate.After the treatment of hydroxyethyl cellulose, generally not easy to form a block or spherical, nor will the addition of water to form an insoluble spherical colloid.

Polyurethane catalyst

The catalysts commonly used in the synthesis of polyurethane and its raw materials are mainly tertiary amine catalysts and organometallic compounds.There are many kinds of tertiary amines and organometallic compounds. Considering various factors, only more than 20 are commonly used in the production of polyurethane.

Amine catalyst

Amine catalysts are generally used in the production of polyurethane foam plastics, which are mainly divided into the following categories:

The aliphatic amine catalysts include N, N-dimethylcyclohexylamine, double (2-dimethylaminoethyl) ether,N,N,N',N' -tetramethylalkyl diamine, triethylamine,N, N-dimethylbenzylamine, etc.

Alicyclic amine catalysts include solid amine, N-ethyl morpholine, N-methyl morpholine,N,N '-diethylpiperazine, etc.

Alcohol compounds catalysts are triethanolamine, DMEA and so on.

Aromatic amines include pyridine,N,N '-dimethylpyridine and so on.

Organometallic catalyst

In polyurethane elastomers and adhesive, coating, sealant, waterproof coatings, pavement materials formula, tin two lauric acid ester (DY - 12), and other organic metal catalyst is most commonly used, it is to promote isocyanate and hydroxyl reflect is very effective, but in a formula with water with water and the acceleration of the reaction of isocyanate also to have certain role;Special catalyst such as organic lead can be used in the formula of plastic track.

Organometallic compounds include carboxylic acid, metal alkyl compounds, the main metal elements contained in tin, potassium, lead, mercury, zinc, etc., the most commonly used is organometallic tin compounds.