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Glycol Ethers
1. GLYCOL ETHERS • long-term shelf-life of products
• work at low concentrations
Glycol ethers, with both an ether and • a lack of residual odour
alcohol functional group in the same • good biodegradability
molecule, are one of the most versatile • Improve the wetting properties of
classes of organic solvents from which water- based products
liquid substances derived. They are both
hydrophilic (soluble in water) and Glycol Ether products are produced
lipophilic (soluble in oils). As they are through continuous processes of
excellent co-solvents, they enable non- selectively reacting an alcohol and
miscible substances to be mixed with each ethylene oxide.
other. Glycol ethers are characterized by their
excellent solvency, chemical stability and
The chemical structure of long compatibility with water and a number of
hydrocarbon chain resist to solubility in organic solvents. The dual functionality
water, while ether or alcohol groups present in the EGBE and DEGBE solvents
introduce the promoted hydrophilic accounts for their unique solvency
solubility performance. This surfactant-like properties. As a class of products, EGBE
structure provides the compatibility and DEGBE solvents are:
between water and a number of organic
solvents, and the ability to couple unlike • Mild-odored solvents for many resins,
phases. oils, waxes, fats and dyestuffs
Because of these specific properties, they • Coupling agents for many water/organic
are included in the composition of many systems
products for use by industry or the general
public. • Miscible with a wide range of polar and
non-polar organic solvents
The main properties of glycol ethers are
that they are soluble in water and in oils. • Miscible with water in most cases
These properties make them very useful
for numerous applications for industry and A coupling agent is defined as a compound
the general public. Indeed glycol ethers which provides a chemical bond between
very often play a crucial role in the two dissimilar materials, usually an
formulation of products that would not inorganic and an organic.
function without them. Some of them make
it possible to use water for dissolving This strong solvency leads to the selection
substances that would otherwise remain of certain EGBE and DEGBE solvents for
insoluble. This means that their use, in low formulations of cleaners.
concentrations, has avoided the need to
resort to other solvents that may present • Solvents for grease and grime in
risks to safety (inflammability) and/or for industrial cleaning and specialty
the environment (evaporation of volatile formulations
organic compounds).
• Coupling solvents for hard-surface
Glycol ethers also have other cleaners and other soap-hydrocarbon
characteristics: systems
• long-term stability of formulations
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2. All international research and evaluations EGBE is an organic solvent with the
show that glycol ethers do not accumulate formula C6H14O2. It is a colorless liquid,
in the environment, because they break ether-like odour. It is a butyl ether
down in the air within a few hours by of ethylene glycol. It is a type of glycol
photolysis (= breakdown reaction triggered ether and remains the single most widely
by sunlight) and they are biodegradable produced glycol ether. It is primarily used
within a few days in the aquatic as a solvent. It evaporates quickly and is
environment. completely soluble in water.
Glycol Ether products would be classified EGBE is sold commercially under a
as “readily”/rapidly biodegradable and variety of names. EGBE is also referred to
would not be expected to persist in the by its chemical names:
natural environment for a significant
period of time. • 2-Butoxy-1-ethanol
• Ethylene glycol monobutyl ether
Under the right conditions, EGBE and • 2-Butoxyethanol
DEGBE can be used for professional • Ethylene glycol butyl ether (EGBE)
applications without presenting a risk to • Butyl CELLOSOLVE
health. • Butyl glycol ether (BGE)
According to Human health classifications
for glycol ethers according to the EU
dangerous substances directive
(67/548/EEC)
EGBE Line Structure
Glycol Irritant/
Harmful
ether corrosive
EGBE R36/38 R20/21/ 22
DEGBE R36 N/C
EGBE Space-filling Model
R20: harmful by inhalation Chemical Name Ethylene Glycol
R21: harmful in contact with skin Monobutyl Ether
R22: harmful if swallowed CAS Number 111-76-2
R36: irritating to eyes Molecular Formula C6H14O2
R38: irritating to skin Appearance Colorless, liquid
Boiling Point 171°C(340°F) at 760 mmHg
ETHYLENE GLYCOL BUTYL Structure C4H9-O-CH2-CH2-OH
ETHER (EGBE) Solubility Miscible in both water and
organic solvents
EGBE is a key ingredient in hundreds of
products ranging from industrial and
consumer cleaning solutions to water- and
solvent-based paints and coatings. EGBE’s n-Butanol Ethylene Oxide EGBE
popularity stems from several special
performance characteristics that also EGBE is produced by reacting ethylene
provide economic value. oxide and normal butanol (n-butanol) using
a catalyst. If the ratio of ethylene oxide to
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3. n-butanol is greater than one, di- and tri- and soaps are miscible with EGBE.
ethylene glycol monoethers are produced Accordingly, this product
along with the EGBE. is widely employed as a coupling agent to
stabilize immiscible ingredients in
industrial metal cleaners, in vapor
degreasers, in the clarification of oil-water
dispersions, and in the formulation of
concentrated liquid cleaners. In fabric
cleaners, EGBE assists in removing water-
soluble stains and aids in brightening the
colors of garments. It improves penetrating
and wetting action of phosphoric acid-type
rust removers.
EGBE is used in coatings and cleaner When added to cleaners, EGBE helps lift
applications, including many in consumer soil and keeps it suspended until it can be
markets. It is used for: rinsed or wiped away. Because EGBE’s
chemical structure includes an ether and an
• Active solvent for solvent-based alcohol, it can attack water-insoluble oils
coatings and greases and water-soluble stains.
EGBE thus offers manufacturers a variety
• Coalescent for industrial water-based
of cleaning capabilities, from heavy-duty
coatings
industrial jobs to milder janitorial and
• Coupling agent for architectural water-
household uses.
borne coatings
• Coupling agent and solvent in EGBE is compatible with both petroleum
household and industrial cleaners, rust solvents and water, it is found in a wide-
removers, hard surface cleaners and range of coatings – from automotive and
disinfectants packaging coatings to wood furniture
• Primary solvent in solvent-based silk finishes. It is used widely in water-based
screen printing inks industrial paints and coatings.
• Coupling agent for resins and dyes in
water-based printing inks In household products, EGBE uses include
• Solvent for agricultural pesticides glass and tile cleaners, waxes, rust
removers and metal polishes. The same
EGBE has been used for more than half a properties that allow EGBE to dissolve and
century. Today it is used extensively in hold soils and stains in suspension make
both water- and solvent-based coatings and the compound an effective ingredient in
industrial and consumer cleaners. Cleaners water-based protective paints and coatings.
made with EGBE can remove oils, fats, EGBE also acts to dissolve or suspend
waxes, greases and baked-on or ground-in pigments and resins until the coating is
residues from floors, walls, glass, metal applied to surfaces. Once the coating is
parts, and equipment. Paints and coatings applied, EGBE is designed to evaporate,
that use EGBE range from lacquers, leaving a uniform, dry finish.
varnishes and enamels to water-based
coatings and inks. Although some glycol ethers have been
EGBE offers superior performance in shown to cause adverse reproductive
many hard-surface cleaners and related effects and birth defects in laboratory
Cleaning formulations. Mineral oils, water animals, EGBE does not show the same
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4. pattern of toxicity as these other glycol DIETHYLENE GLYCOL BUTYL
ethers. Human experience and animal ETHER (DEGBE)
studies have shown that EGBE is unlikely
to cause adverse health effects when DEGBE is a clear, liquid with a mild ether
products are used as directed. Still, when odor. It is a solvent with an extremely low
used improperly, EGBE can cause eye, rate of evaporation and is completely water
respiratory tract and skin irritation and soluble and serves as a mutual solvent for
even burns. soaps, oils and water and as a component
of liquid cleaners, “soluble” oils and textile
EGBE is unlikely to cause adverse oils. It has found increased use in Cleaning
environmental impact because it is not formulations because of its good solvency
persistent, does not bioaccumulate (build for greasy soils and waxes.
up in the food chain), is readily DEGBE is sold commercially under a
biodegradable and has low toxicity to variety of names. DEGBE is also referred
aquatic organisms. It moves to water when to by its chemical names:
it is released because of its high
miscibility, low volatility and minimal • 2-(2-Butoxyethoxy)ethanol
tendency to bind to soil or sediment. It • Diethylene glycol monobutyl ether
degrades rapidly in water. • Diethylene glycol butyl ether (DGBE)
• Butyl CARBITOL™ solvent
EGBE is one of the most versatile • Butoxydiglycol
chemicals in the marketplace today for a • Diglycol monobutyl ether
wide variety of uses. Human experience
and animal studies have shown that it is
unlikely to cause adverse health effects
when used as directed and in accordance
with product safety information and good
hygiene practices. EGBE studies also show
it is unlikely to cause adverse
environmental impacts because it is not DEGBE Line Structure
persistent, does not bioaccumulate, and has
low toxicity to aquatic organisms. Chemical Name Diethylene Glycol
Monobutyl Ether
Research continues so that industry, CAS Number 112-34-5
government and academic scientists can Molecular Formula C8H18O3
increase our knowledge about EGBE. Appearance clear hydroscopic liquid
Boiling Point 231°C at 760 mmHg
As with all chemicals, EGBE should be Structure C4H9(OCH2CH2)2OH
used with care and in accordance with Solubility Miscible in both water and
governmental regulations. EGBE and organic solvents
products containing EGBE are not
intended to be ingested. Airborne
concentrations of EGBE should be
n-Butanol Ethylene Oxide DEGBE
maintained below permissible exposure
limits. Consistent with governmental
DEGBE is used as a solvent in coatings
standards, skin contact with EGBE before
and cleaner applications for industrial and
it is diluted in commercial formulations
consumer markets. It is also used as a
should be avoided.
chemical intermediate to produce
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5. diethylene glycol monobutyl ether acetate water. Because of these properties,
(DBA) and some herbicides, insecticides DEGBE poses a low risk to the
and plasticizers. DEGBE is also used in environment.
hydraulic brake fluid applications.
Specifically, it is used as:
• Coupling agent and solvent in household
and
industrial cleaners, rust removers, hard
surface cleaners and disinfectants
• Latex coalescent in water-based
architectural
and industrial coatings
• Primary solvent in solvent-based silk
screen printing inks
• Coupling solvent for resins and dyes in
water-based printing inks
• Solvent for ball point and felt tip pen
inks, and textile dyeing and printing
• Coalescent for latex adhesives
• Deactivator and stabilizer for agricultural
pesticides
• Diluent in hydraulic brake fluid
applications
DEGBE is practically non-toxic to aquatic
organisms on an acute basis. It is readily
biodegradable and does not bioaccumulate
(build up in the food chain). DEGBE
moves to water when it is released because
of its high solubility, low volatility and
high soil mobility. It degrades rapidly in
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