EMANON HE

Emanon HE is a vegetable origin non-ionic surfactant. 
Emanon HE can be used as co-emulsifier, condition agent, emollient and perfumes and extract solubilizer. 
Emanon HE's use can affect to the final viscosity of the formula (lower viscosity). 

CAS:    68201-46-7

Emanon HE can soluble in alcohol or water.
Emanon HE is a polymer which is hydrolyzed by ethylene oxide. 
Emanon HE has no toxicity and irritation. 
Emanon HE is widely used in various pharmaceutical preparations. 
The toxicity of low molecular weight Emanon HE is relatively large. 
In general, the toxicity of diols is very low. 
Topical application of Emanon HE, especially mucosal drug, can cause irritant pain. 
In topical lotion, Emanon HE can increase the flexibility of the skin, and has a similar moisturizing effect with glycerin. 
Diarrhoea can occur in large doses of oral administration. 
In injection, the maximum Emanon HE concentration is about 30% (V/V). 
Emanon HE could occur when the concentration is more than 40% (V/V).

Emanon HE are a family of linear polymers formed by a base-catalyzed condensation reaction with repeating ethylene oxide units being added to ethylene. 
The molecular formula is (C2H4O)multH2O where mult denotes the average number of oxyethylene groups. 
The molecular weight can range from 200 to several million corresponding to the number of oxyethylene groups. 
The higher-molecular-weight materials (100 000 to 5 000 000) are also referred to as Emanon HE. 
The average molecular weight of any specific Emanon HE product falls within quite narrow limits (°5%). 

The number of ethylene oxide units or their approximate molecular weight (e.g., PEG-4 or PEG-200) commonly designates the nomenclature of specific Emanon HE. 
Emanon HE with amolecular weight less than 600 are liquid, whereas those of molecular weight 1000 and above are solid. 
These materials are nonvolatile, water-soluble, tasteless, and odorless. 
They are miscible with water, alcohols, esters, ketones, aromatic solvents, and chlorinated hydrocarbons, but immiscible with alkanes, paraffins, waxes, and ethers.

Any of several condensa-tion polymers of Emanon HE with thegeneral formula HOCH2(CH2OCH2)nCH2OH orH(OCH2CH2)nOH. 
Average molecular weightsrange from 200 to 6000. 
Properties vary with molec-ular weight.

Emanon HE Chemical Properties
Melting point: 64-66 °C
Boiling point: >250°C
Density: 1.27 g/mL at 25 °C
Vapor density: >1 (vs air)
Vapor pressure: <0.01 mm Hg ( 20 °C)
Refractive index: n20/D 1.469
Fp: 270 °C
Storage temp.: 2-8°C
Solubility H2O: 50 mg/mL, clear, colorless
Form: waxy solid
Color: White to very pale yellow
Specific Gravity: 1.128
PH: 5.5-7.0 (25℃, 50mg/mL in H2O)
Water Solubility: Soluble in water.
Sensitive: Hygroscopic
λmax: λ: 260 nm Amax: 0.6
λ: 280 nm Amax: 0.3
Merck: 14,7568
Stability: Stable. Incompatible with strong oxidizing agents.
LogP: -0.698 at 25℃
NIST Chemistry Reference: Emanon HE (25322-68-3)
EPA Substance Registry System: Emanon HE (25322-68-3)

The USP32–NF27 describes Emanon HE as being an addition polymer of ethylene oxide and water. 
Emanon HE grades 200–600 are liquids; grades 1000 and above are solids at ambient temperatures.
Liquid grades (PEG 200–600) occur as clear, colorless or slightly yellow-colored, viscous liquids. 
They have a slight but characteristic odor and a bitter, slightly burning taste. 
Emanon HE can occur as a solid at ambient temperatures.
Solid grades (PEG>1000) are white or off-white in color, and range in consistency from pastes to waxy flakes. 
They have a faint, sweet odor. 
Grades of Emanon HE and above are available as freeflowing milled powders.

Uses    
Emanon HE is a binder, coating agent, dispersing agent, flavoring adjuvant, and plasticizing agent that is a clear, colorless, viscous, hygroscopic liquid resembling paraffin (white, waxy, or flakes), with a ph of 4.0–7.5 in 1:20 concentration. 
Emanon HE is soluble in water (mw 1,000) and many organic solvents.
Emanon HE is a binder, solvent, plasticizing agent, and softener widely used for cosmetic cream bases and pharmaceutical ointments. 
Emanon HE is quite humectant up to a molecular weight of 500. 
Beyond this weight, their water uptake diminishes.
Emanon HE molecules of approximately 2000 monomers. 

Emanon HE is used in various applications from industrial chemistry to biological chemistry. 
Recent research has shown PEG m aintains the ability to aid the spinal cord injury recovery process, helping the nerve impulse conduction process in animals. 
In rats, Emanon HE has been shown to aid in the repair of severed sciatic axons, helping with nerve damage recovery. 
Emanon HE is industrially produced as a lubricating substance for various surfaces to reduce friction. 
Emanon HE is also used in the preparation of vesicle transport systems in with application towards diagnostic procedures or drug delivery methods.
A polymer used to precipitate proteins, viruses, DNA and RNA.

Application in Biomedicine    
Emanon HE is also known as polyoxirane (PEO). 
Emanon HE is a linear polyether obtained by ring opening polymerization of ethylene oxide. 
The main uses in the field of biomedicine are as follows:
Contact lens liquid. 
The viscosity of Emanon HE solution is sensitive to the shear rate and it is not easy for bacteria to grow on polyethylene glycol.
Synthetic lubricants. 
The condensation polymer of Emanon HE and water. 
Emanon HE is a cream matrix for preparing water-soluble drugs.
Emanon HE can also be used as a solvent for acetylsalicylic acid and caffeine, which is difficult to dissolve in water.
Drug sustained-release and immobilized enzyme carrier. 
The Emanon HE solution is applied to the outer layer of the pill to control the diffusion of drugs in the pill so as to improve the efficacy.

Surface modification of medical polymer materials. 
The biocompatibility of medical polymer materials in contact with blood can be improved by adsorption, interception and grafting of two amphiphilic copolymers containing Emanon HE on the surface of medical polymers.
Emanon HE can make the membrane of the alkanol contraceptive pill.
Emanon HE can make hydrophilic anticoagulant polyurethane.
Emanon HE is an osmotic laxative. 
Emanon HE can increase osmotic pressure and absorb moisture in the intestinal cavity, which makes the stool soften and increase in volume, resulting in bowel movement and defecation.
Denture fixing agent. 
Emanon HE nontoxic and gelatinous nature can be used as a component of denture fixer.
Emanon HE is commonly used to promote cell fusion or protoplast fusion and help organisms (such as yeasts) to take DNA in transformation. 
Emanon HE absorbs water from the solution, so it is also used to concentrate the solution.

Pharmaceutical Applications    
Emanon HE is widely used in a variety of pharmaceutical formulations, including parenteral, topical, ophthalmic, oral, and rectal preparations. 
Emanon HE has been used experimentally in biodegradable polymeric matrices used in controlled-release systems.
Emanon HE are stable, hydrophilic substances that are essentially nonirritant to the skin;They do not readily penetrate the skin, although the polyethylene glycols are water-soluble and are easily removed from the skin by washing, making them useful as ointment bases.
Solid grades are generally employed in topical ointments, with the consistency of the base being adjusted by the addition of liquid grades of Emanon HE.
Mixtures of Emanon HE can be used as suppository bases,for which they have many advantages over fats. 

For example, the melting point of the suppository can be made higher to withstand exposure to warmer climates; release of the drug is not dependent upon melting point; the physical stability on storage is better; and suppositories are readily miscible with rectal fluids. 
Emanon HE have the following disadvantages: they are chemically more reactive than fats; greater care is needed in processing to avoid inelegant contraction holes in the suppositories; the rate of release of water-soluble medications decreases with the increasing molecular weight of the Emanon HE; and polyethylene glycols tend to be more irritating to mucous membranes than fats.
Aqueous Emanon HE solutions can be used either as suspending agents or to adjust the viscosity and consistency of other suspending vehicles. 

When used in conjunction with other emulsifiers, Emanon HE can act as emulsion stabilizers. 
Liquid Emanon HE is used as water-miscible solvents for the contents of soft gelatin capsules. 
However, they may cause hardening of the capsule shell by preferential absorption of moisture from gelatin in the shell.

In concentrations up to approximately 30% v/v, Emanon HE has been used as the vehicle for parenteral dosage forms. 
In solid-dosage formulations, higher-molecular-weight Emanon HE can enhance the effectiveness of tablet binders and impart plasticity to granules.
However, they have only limited binding action when used alone, and can prolong disintegration if present in concentrations greater than 5% w/w. 
When used for thermoplastic granulations,a mixture of the powdered constituents with 10–15% w/w PEG 6000 is heated to 70–75°C. 
The mass becomes pastelike and forms granules if stirred while cooling. 
This technique is useful for the preparation of dosage forms such as lozenges when prolonged disintegration is required. 
Emanon HE can also be used to enhance the aqueous solubility or dissolution characteristics of poorly soluble compounds by making solid dispersions with an appropriate Emanon HE.
Animal studies have also been performed using Emanon HE as solvents for steroids in osmotic pumps. 

In film coatings, solid grades of Emanon HE can be used alone for the film-coating of tablets or can be useful as hydrophilic polishing materials. 
Solid grades are also widely used as plasticizers in conjunction with film-forming polymers.
The presence of Emanon HE in film coats, especially of liquid grades, tends to increase their water permeability and may reduce protection against low pH in enteric-coating films. 
Emanon HE are useful as plasticizers in microencapsulated products to avoid rupture of the coating film when the microcapsules are compressed into tablets.
Emanon HE grades with molecular weights of 6000 and above can be used as lubricants, particularly for soluble tablets. 
The lubricant action is not as good as that of magnesium stearate, and stickiness may develop if the material becomes too warm during compression. 

An antiadherent effect is also exerted, again subject to the avoidance of overheating.
Emanon HE have been used in the preparation of urethane hydrogels, which are used as controlled-release agents. 
Emanon HE has also been used in insulin-loaded microparticles for the oral delivery of insulin;it has been used in inhalation preparations to improve aerosolization; Emanon HE nanoparticles have been used to improve the oral bioavailability of cyclosporine; Emanon HE has been used in self-assembled polymeric nanoparticles as a drug carrier;and copolymer networks of Emanon HE grafted with poly(methacrylic acid) have been used as bioadhesive controlled drug delivery formulations.

Production Methods    
Emanon HE polymers are formed by the reaction of ethylene oxide and water under pressure in the presence of a catalyst.

Preparation    
The ring-opening polymerization of ethylene oxide is readily effected by a variety of ionic reagents and several types of polymer have been prepared. 
For commercial purposes, poly(ethylene oxide)s of low molecular weight and of very high molecular weight are of interest.
(a) Low molecular weight polymers
Poly(ethylene oxide)s of low molecular weight, i.e. below about 3000, are generally prepared by passing ethylene oxide into ethylene glycol at 120-150C and about 0.3 MPa (3 atmospheres) pressure, using an alkaline initiator such as sodium hydroxide. 

The polymers produced by these methods are thus terminated mainly by hydroxy groups (a few unsaturated end-groups are also formed) and are often referred to as poly(ethylene glycol)s. 
Poly(ethylene glycol)s with molecular weights in the range 200-600 are viscous liquids which find use as surfactants in inks and paints and as humectants. 
At molecular weights above about 600, Emanon HE is low-melting waxy solids, uses of which include pharmaceutical and cosmetic bases, lubricants and mould release agents.
Emanon HE may be noted that homogeneous cationic polymerization of ethylene oxide also generally leads to low molecular weight products; typical initiators include aluminium chloride, boron trifluoride and titanium tetrachloride. 
Systems of this type are not utilized on a commercial scale.

(b) High molecular weight polymers
Poly(ethylene oxide)s of molecular weight ranging from about 100000 to 5 x 106 and above are available. 
Details of the techniques used to manufacture these polymers have not been disclosed, but the essential feature is the use of (generally) heterogeneous initiator systems. 
Effective initiators are mainly of two types, namely alkaline earth compounds (e.g. carbonates and oxides of calcium, barium and strontium) and organometallic compounds (e.g. aluminium and zinc alkyls and alkoxides, commonly with added coinitiators).

Unlike the low molecular weight poly(ethylene oxide)s, the high molecular weight polymers are tough and extensible. 
They are highly crystalline, with a melting point of 66C.
Unlike most water-soluble polymers, the high molecular weight poly(ethylene oxide)s may be melt processed; they may be injection moulded, extruded and calendered without difficulty.
Poly(ethylene oxide)s are soluble in an unusually broad range of solvents, which includes water; chlorinated hydrocarbons such as carbon tetrachloride and methylene dichloride; aromatic hydrocarbons such as benzene and toluene; ketones such as acetone and methyl ethyl ketone; and alcohols such as methanol and isopropanol. 

There is an upper temperature limit of solubility in water for the high molecular weight poly(ethylene oxide)s; this varies with concentration and molecular weight but is usually between 90 and 100C.
Water-solubility is due to the ability of the polyether to form hydrogen bonds with water; these bonds are broken when the temperature is raised, restoring the anhydrous polymer which is precipated from the solution.
High molecular weight poly(ethylene oxide)s find use as water-soluble packaging films and capsules for such products as laundry powders, colour concentrates, tablets and seeds. 
In solution, the polymers are used as thickeners in pharmaceutical and cosmetic preparations, textile sizes and latex stabilizers.

Manufacturing Process    
Emanon HE was obtained by polymerization of ethylene oxide in an autoclave at 80-100°C using as a catalyst dipotassium alcogolate of polyethylene glycol 400.
Dipotassium alcogolate of Emanon HE was synthesized by a heating of the dry mixture of Emanon HE and potassium hydroxide. 
The molecular weight of polymer was regulated by the ratio of monomer:catalyst.

Toxicity evaluation    
Many years of human experience in the workplace and in the use of consumer products containing polyethylene glycols have not shown any adverse health effects, except in situations where very high doses are administered to hypersusceptible individuals or persons with underlying diseases.

Synonyms
1,2-ethanediol,homopolymer
2-ethanediyl),.alpha.-hydro-.omega.-hydroxy-Poly(oxy-1;Alcox E 160;Alcox E 30;alcoxe30;Poly(ethylene oxide),approx. M.W. 600,000
Poly(ethylene oxide),approx. M.W. 200,000
Poly(ethylene oxide),approx. M.W. 900,000