Quick Search
Methyl cellulose, abbreviated MC, is a kind of long-chain substituted cellulose, in which 27% to 32% of the hydroxyl group exists in the form of methoxy.
The substitution degree affects the physical properties of methyl cellulose such as solubility.
Methylcellulose has an average molecular weight of 10,000 to 220,000.
CAS: 9004-67-5
MF: C20H38O11
MW: 454.50912
EINECS: 232-674-9
Synonyms
adulsin;Methyl cellulose, viscosity 8000 cPs;'TYLOSE'(R) MH 300;'TYLOSE'(R) MH 1000;walsrodermc20000s;FEMA 2696;MethyI cellulose;METHYL CELLULOSE (CMC)
At room temperature, Methyl cellulose exhibits as a white powder or fibrous material, and is non-toxic, non-irritating with non-allergic effect.
Methyl cellulose's apparent relative density is 0.35 to 0.55 (with the real density being 1.26 to 1.30).
Methyl cellulose swells in water into a translucent viscous colloidal solution which is neutral to litmus, insoluble in ethanol, ether and chloroform, but soluble in glacial acetic acid.
Methyl cellulose is tolerant to the effects of acid, alkali, microorganisms, heat, and light and is also not affected by oil and grease, but will burn upon reaching ignition point.
Methyl cellulose is a product composed of cellulose glucose with all or part of three hydroxyls getting methylated.
General products contain a methoxy fraction of 26% to 33% with degree of substitution being 1.7 to 2.2.
Product with substitution degree being 1.3 to 2.6 is soluble in water, pyridine, and acetic acid.
Methyl cellulose is widely used for architecture, such as being used as the adhesive of cement, mortar, and for mudding off the seam.
Methyl cellulose is also used for making film an adhesive in cosmetics, medicine, and food industry.
Methyl cellulose can be also used as a textile sizing agents, synthetic resin dispersing agent, paint film formers and thickeners.
The production method is that: use pulp to produce the alkali cellulose; alkali cellulose is reacted with methyl chloride or dimethyl sulfate in an autoclave and then further refined with warm water to obtain the final product.
Methyl cellulose powder is stable and slightly hygroscopic; it should be placed in an airtight container and stored in a cool dry place.
Methyl cellulose solution is sable in diluted acid or base with pH 3 to 11 at room temperature, and is easy to be destroyed by microbes to be corrupted.
Therefore, the solution should be added into preservatives or subject to autoclaving.
After autoclaving, the change of the solution viscosity is related with pH value.
For solution of pH <4, the viscosity will decrease by more than 20% after autoclaving.
Methyl cellulose (or methylcellulose) is a compound derived from cellulose.
Methyl cellulose is sold under a variety of trade names and is used as a thickener and emulsifier in various food and cosmetic products, and also as a bulk-forming laxative.
Like cellulose, Methyl cellulose is non-digestible, non-toxic, and not an allergen.
In addition to culinary uses, Methyl cellulose is used in arts and crafts such as papier-mâché and is often the main ingredient of wallpaper paste.
Methyl cellulose Chemical Properties
Melting point: 290-305 °C
density: 1.01 g/cm3(Temp: 70 °C)
refractive index: 1.4970
FEMA: 2696 | METHYL CELLULOSE
storage temp.: Room Temperature
solubility: Practically insoluble in hot water, in acetone, in anhydrous ethanol and in toluene. It dissolves in cold water giving a colloidal solution.
form: powder
color: White, yellow-white or grayish-white
Odor: odorless
PH: 5.0 -8.0
biological source: wood (pulp cellulose)
Odor Type: odorless
Water Solubility: SOLUBLE IN COLD WATER
Merck: 14,6040
Dielectric constant: 3.0（Ambient）
Stability: Stable. Incompatible with strong oxidizing agents, bleach, perchloric acid, nitric acid, perchlorates, alkali nitrates, alkali nitrites, calcium oxide.
Major Application: pharmaceutical (small molecule)
Cosmetics Ingredients Functions: BINDING LIGHT STABILIZER VISCOSITY CONTROLLING EMULSION STABILISING
Cosmetic Ingredient Review (CIR): Methyl cellulose (9004-67-5)
InChIKey: YLGXILFCIXHCMC-JHGZEJCSSA-N
EPA Substance Registry System: Methyl cellulose (9004-67-5)
Methyl cellulose is a kind of methyl ether of cellulose.
Methyl cellulose is white or pale yellow or light gray small particles (95% through a 40 mesh sieve), filaments like or powder.
Methyl cellulose is odorless, tasteless and has hygroscopicity with an apparent density of 0.3~0.7g/mL.
When all the R in the structure is Methyl cellulose, the substitution degree is equal to 3, and the methoxy content is 45.57%.
For methylcellulose used as the food additive, the methoxy content should be around 26%~33% which corresponds to a degree of substitution of 1.7 to 2.2.
When the substitution degree is lower than 1.3, it can be dissolved in alkaline.
While methyl cellulose with substitution degree higher than 2.6 is soluble in an organic solvent.
When the degree of substitution is less than 1.3, Methyl cellulose can be dissolved in alkali; for those with substitution degree higher than 2.6, Methyl cellulose is soluble in organic solution.
At the range between 1.3 and 2.6, Methyl cellulose is soluble in cold water, pyridine, aniline, trimethyl formamide, benzyl alcohol and acetic acid.
Aqueous solution is stable at neutral and room temperature; but Methyl cellulose can generate gelation effect and be precipitated at high temperature.
Gelation temperature is dependent on the absolute viscosity and concentration of the solution; solution of large viscosity and high concentration has a relative low gelling temperature.
In the presence of inorganic salts, viscosity can be increased.
Due to that Methyl cellulose belongs to a non-ionic solution, the polyvalent metal is not able to precipitate it; Gelation will only occur when the concentration of the electrolyte and other dissolved substances exceeds a certain limit.
Aqueous solution has surfactant activity and dried to form a thin film; upon heating and cooling, Methyl cellulose will orderly go through the reversible transition from the sol to gel.
Methyl cellulose does not occur naturally and is synthetically produced by heating cellulose with caustic solution (e.g. a solution of sodium hydroxide) and treating it with methyl chloride.
In the substitution reaction that follows, the hydroxyl residues (-OH functional groups) are replaced by methoxide (-OCH3 groups).
Different kinds of methyl cellulose can be prepared depending on the number of hydroxyl groups substituted.
Methyl cellulose is a polymer consisting of numerous linked glucose molecules, each of which exposes three hydroxyl groups.
The Degree of Substitution (DS) of a given form of methyl cellulose is defined as the average number of substituted hydroxyl groups per glucose.
The theoretical maximum is thus a DS of 3.0, however more typical values are 1.3–2.6.
Different methyl cellulose preparations can also differ in the average length of their polymer backbones.
Uses
Methyl cellulose is widely applied in a variety of orally administrated or topical formulations; it is also widely used in cosmetics and food.
After oral administration, methyl cellulose can’t be digested or absorbed so that it is a calorie-free material.
Excessive intake of methyl cellulose may temporarily increase flatulence and even cause esophageal obstruction upon insufficient water intake.
However, methyl cellulose has a laxative effect.
Methyl cellulose is a hydrophilic colloid and is the high-viscosity cellulose derivatives.
Methyl cellulose is non-toxic and caustic, hygroscopic and can expand into a colloidal suspension in cold water.
Methyl cellulose is also insoluble in hot water, alcohol, ether, chloroform and saturated salt solution but is soluble in glacial acetic acid and the mixture of equal amount of alcohol and chloroform solution.
Methyl cellulose's solution may be agglomerated by salts, polybasic acid, phenol and tannin with adding ethanol being able to prevent this agglomeration effect.
Methyl cellulose can’t be digested, absorbed in the intestine.
Methyl cellulose can absorb moisture, mixed with water to form a large volume of hydrophilic gum, and increase the stool volume and soften it, and also stimulate the gut peristalsis to promote the defecation.
In patients with diarrhea, because the product can absorb moisture, so it reduces the intestine liquidity to take the antidiarrheal effect.
Oral administration: 1~4g/d together with taking large amounts of water as a bulk laxative for the treatment of constipation.
Methyl cellulose has been worked as anorectic agents for controlling appetite and inducing weight loss.
But Methyl cellulose doesn’t have a reliable effect.
Methyl cellulose can also be used as: adhesives which are suitable for choosing low or moderate viscosity grade plastic with both adding powder and solution working well.
Methyl cellulose is used for improving drug dissolution rate or disintegration rate; the general concentration is 1% to 2%.
For gels, thickening gels and creams: Methyl cellulose is appropriate to choose high-viscosity grade. Suspending agents and thickening agents, solutions can replace syrup; for thickening, use a concentration of up to 5%.
For disintegrating agents, Methyl cellulose is commonly used at a concentration of 2% to 10%.
For emulsifier, Methyl cellulose is generally recommended to use low-viscosity grade at a concentration of 1% to 5%. For eye drops, we should use high-viscosity grade.
Methyl cellulose can be used as thickeners; stabilizer; emulsifier; excipients; dispersant; binders; substitutes of film-forming agent hydrosol.
Methyl cellulose can also be used in mayonnaise, shortenings and some other foods.
Because of that the materials can’t digested in the body, Methyl cellulose can maintain several times amount of water, resulting in satiety; it can be used in crackers, waffles and other food for taking effect.
For application, first 1/5 of the required amount of water for moistening the powder, together with cold water (necessary, to add ice) for mixing well.
EEC: approved for using at frozen foam products, potato chips, soft drinks, special dietary foods, baked goods filling, the top material for foaming, sauces, and sauces.
Methyl cellulose can also be used in mayonnaise, shortenings and some other foods.
Because of that the materials can’t digested in the body, Methyl cellulose can maintain several times amount of water, resulting in satiety; it can be used in crackers, waffles and other food for taking effect.
For application, first 1/5 of the required amount of water for moistening the powder, together with cold water (necessary, to add ice) for mixing well.
EEC: approved for using at frozen foam products, potato chips, soft drinks, special dietary foods, baked goods filling, the top material for foaming, sauces, and sauces.
Methyl cellulose is widely used in the architecture industry such as the mixture agent for cement, plaster, and clay seams.
Methyl cellulose can also be used as adhesive film-forming agent in cosmetics, medicine, and food industry; also can be used as sizing agents for spinning, and printing and dyeing, synthetic resin dispersing agent, paint film formers and thickeners.
Methyl cellulose is a very stable material which is resistant to acid, alkalis, microorganisms, and heating.
Methyl cellulose can be excrete out from the human body without any change.
Methyl cellulose is used for synthetic resin dispersing agent, film-forming agent of painting, thickener, binder materials, textile sizing agent, and the film-forming agent in the pharmaceutical and food industries.
Methyl cellulose is a gum composed of cellulose in which the meth- oxyl groups replace the hydroxyl groups.
Methyl cellulose is soluble in cold water but insoluble in hot water.
solutions increase in viscosity upon heating, gel at 50–55°c, and liquefy upon cooling.
Methyl cellulose is used in baked goods for moisture retention, and in fruit pie fillings for the reduction of water absorption into the pie crust during baking.
Methyl cellulose is also used in breaded shrimp where it functions to form an oil barrier film.
Methyl cellulose is used as a thickener and an emulsifier in various food and cosmetic products; as a gel in advanced cookery and as a lubricant.
Methyl cellulose is also involved in the treatment of constipation.
Methyl cellulose acts as a buffer additive in capillary electrophoresis to control electoosmotic flow for improved separations.
In paper and textile industries, Methyl cellulose is used as a sizing, thereby protecting the fibers from water or oil.
Thickener for aqueous and non-aqueous systems, clear films with grease resistance, binders, lubricants, steric stabilizer and water retention aid.
As a substitute for water-soluble gums; to render paper greaseproof, in adhesives, as thickening agent in cosmetics, as protective colloid in emulsions, as binder and stabilizer in foods.
As fat replacer in the formulation of dietetic foods.
Medical
Constipation
Methyl cellulose is used to treat constipation and is classified as a bulk forming laxative.
Methyl cellulose works by increasing the amount of stool present which improves intestinal contractions. Effects generally occur within three days.
Methyl cellulose is taken orally with sufficient water.
Side effects may include abdominal pain.
Methyl cellulose is available over the counter.
Methyl cellulose is sold under the brand name Citrucel among others.
Artificial tears and saliva
The lubricating property of methylcellulose is of particular benefit in the treatment of dry eyes.
Solutions containing methyl cellulose or similar cellulose derivatives are used as substitute for tears or saliva if the natural production of these fluids is disturbed.
Medication manufacturing
Methyl cellulose is used in the manufacture of drug capsules; its edible and nontoxic properties provide a vegetarian alternative to the use of gelatin.
Consumer products
Thickener and emulsifier
Methyl cellulose is occasionally added to hair shampoos, tooth pastes and liquid soaps, to generate their characteristic thick consistency.
This is also done for foods, for example ice cream or croquette.
Methylcellulose also prevents the separation of emulsions because it is an emulsion stabilizer.
Food
The E number of methyl cellulose as food additive is E461.
Methyl cellulose is hydroxypropyl methylcellulose, which is more soluble in water.
Methylcellulose, as a gel, has the unique property of setting when hot and melting when cold.
In some meat analogues that are intended to replicate the texture of meat, methyl cellulose is used as an ingredient, typically in concentrations less than 2%.
Lubricant
Methyl cellulose may be used in personal lubricant.
Construction materials
Methyl cellulose finds a major application as a performance additive in construction materials.
Methyl cellulose is added to mortar dry mixes to improve the mortar's properties such as workability, open and adjustment time, water retention, viscosity, adhesion to surfaces etc.
Construction grade methyl cellulose is not to be identified with food and pharmaceutical grade methyl cellulose and hydroxypropyl methyl cellulose, as it may be cross-linked with glyoxal for easy dispersion in water.
The construction materials can be cement-based or gypsum-based.
Notable examples of dry mixture mortars which utilize methyl cellulose include tile adhesives, EIFS, insulating plasters, hand-trowelled and machine-sprayed plaster, stucco, self-leveling flooring, extruded cement panels, skim coats, joint & crack fillers, and tile grouts.
Typical usage is about 0.2% – 0.5% of total dry powder weight for dry mixtures.
Derivatives of methyl cellulose which improve performance characteristics include hydroxypropyl methyl cellulose (HPMC) and hydroxyethyl methyl cellulose (HEMC).
These derivatives typically improve the characteristics such as water retention, vertical surface slip resistance, open time, etc.
Production methods
1. Use Pulp to prepare the base fiber; then have etherification reaction to obtain methyl chloride.
According to different sources, pulp can be classified into cotton pulp, wood pulp, straw pulp, etc.,
Methyl cellulose is commonly used in industrial of wood pulp and cotton pulp (cotton linters).
The cellulose in the pulp itself is difficult to have reaction with methyl chloride; it must first be made into alkali cellulose.
Use 1 part of cellulose to be combined with 0.9-1.2 parts of sodium hydroxide and 0.9 to 1.2 parts (all by weight) of water for soak at 30 °C for 1-2h.
Then compress to remove excess alkali to obtain the bulk-like alkali cellulose.
Break Methyl cellulose into pieces to loosen the alkali cellulose and make it more uniform; with the reaction with the oxygen in the air, alkaline cellulose is degraded and its polymerization is also reduced to achieve the purpose of regulating the viscosity.
The alkali cellulose which has undergone the above aging process is further suspended in an excess of methyl chloride (typically 10-15 times of the weight of pulp) for taking reaction for about 5h at 60-70 °C to complete the etherification reaction with the corresponding pressure of about 1.7MPa .
Post-processing of the products includes washing and drying of the finished product.
Is generally washed in hot water of 80-90 °C; add an appropriate amount of hydrochloric acid (or sulfuric acid) for neutralization, and further add it into oxalic acid to make it form complex with iron and heavy metal which is removed together with sodium chloride during the washing step by water.
The product was washed and dehydrated, dried to obtain methyl cellulose products.
2. Use alkali to treat wood pulp or cotton, further use methyl chloride to methylate the alkali to obtain the final product.
Some industrial products contain small amounts (up to 5%) hydroxyethyl and/or cellulose displaced by hydroxypropyl.
For these products, the calculation of content index should follow the percentage of methoxy group plus percentage of ethoxy group and/or percentage of propoxy with "total alkoxy" representing the content.
Production Methods
Methyl cellulose is prepared from wood pulp (cellulose) by treatment with alkali followed by methylation of the alkali cellulose with methyl chloride.
Methyl cellulose is then purified and ground to powder form.
Pharmaceutical Applications
Methyl cellulose is widely used in oral and topical pharmaceutical formulations;
In tablet formulations, low- or medium-viscosity grades of methylcellulose are used as binding agents, the methylcellulose being added either as a dry powder or in solution.
Highviscosity grades of methylcellulose may also be incorporated in tablet formulations as a disintegrant.
Methyl cellulose may be added to a tablet formulation to produce sustained-release preparations.
Tablet cores may also be spray-coated with either aqueous or organic solutions of highly substituted low-viscosity grades of methylcellulose to mask an unpleasant taste or to modify the release of a drug by controlling the physical nature of the granules.
Methyl cellulose coats are also used for sealing tablet cores prior to sugar coating.
Low-viscosity grades of methylcellulose are used to emulsify olive, peanut, and mineral oils.
They are also used as suspending or thickening agents for orally administered liquids, methyl cellulose commonly being used in place of sugar-based syrups or other suspension bases.
Methyl cellulose delays the settling of suspensions and increases the contact time of drugs, such as antacids, in the stomach.
High-viscosity grades of methylcellulose are used to thicken topically applied products such as creams and gels.
In ophthalmic preparations, a 0.5–1.0% w/v solution of a highly substituted, high-viscosity grade of methyl cellulose has been used as a vehicle for eye drops.
However, hypromellose-based formulations are now preferred for ophthalmic preparations.
Methyl cellulose is also used in injectable formulations.
Therapeutically, methyl cellulose is used as a bulk laxative; it has also been used to aid appetite control in the management of obesity, but there is little evidence supporting its efficacy.
