POLYDIMETHYLSILOXANE (PDMS)

CAS Number : 9006-65-9 
EC  Number : 613-156-5
ECHA InfoCard : 100.126.442 
PubChem CID   : 24705
Chemical formula : CH3[Si(CH3)2O]nSi(CH3)3
Molecular Formula : C8H24O2Si3
Density     : 0.965 g/cm3

IUPAC name : 
poly(dimethylsiloxane)

Other names : 
-PDMS
-dimethicone
-dimethylpolysiloxane
-E900

Polydimethylsiloxane (PDMS), also known as dimethylpolysiloxane or dimethicone, belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones.
PDMS is the most widely used silicon-based organic polymer, as its versatility and properties lead to many applications.
Polydimethylsiloxane (PDMS) is particularly known for its unusual rheological (or flow) properties. 
PDMS is optically clear and, in general, inert, non-toxic, and non-flammable. 
Polydimethylsiloxane (PDMS) is one of several types of silicone oil (polymerized siloxane). 
Its applications range from contact lenses and medical devices to elastomers; it is also present in shampoos (as it makes hair shiny and slippery), food (antifoaming agent), caulk, lubricants and heat-resistant tiles.

Structure of Polydimethylsiloxane (PDMS)
The chemical formula for Polydimethylsiloxane (PDMS) is CH3[Si(CH3)2O]nSi(CH3)3, where n is the number of repeating monomer [Si(CH3)2O] units.
Industrial synthesis can begin from dimethyldichlorosilane and water by the following net reaction:

n Si(CH3)2Cl2 + (n + 1) H2O → HO[−Si(CH3)2O−]nH + 2n HCl

The polymerization reaction evolves hydrochloric acid. For medical and domestic applications, a process was developed in which the chlorine atoms in the silane precursor were replaced with acetate groups. 
In this case, the polymerization produces acetic acid, which is less chemically aggressive than HCl. 
As a side-effect, the curing process is also much slower in this case. 
The acetate is used in consumer applications, such as silicone caulk and adhesives.

Branching and capping of Polydimethylsiloxane (PDMS)
Hydrolysis of Si(CH3)2Cl2 generates a polymer that is terminated with silanol groups (–Si(CH3)2OH). 
These reactive centers are typically "capped" by reaction with trimethylsilyl chloride:

2 Si(CH3)3Cl + [Si(CH3)2O]n-2[Si(CH3)2OH]2 → [Si(CH3)2O]n-2[Si(CH3)2OSi(CH3)3]2 + 2 HCl

Silane precursors with more acid-forming groups and fewer methyl groups, such as methyltrichlorosilane, can be used to introduce branches or cross-links in the polymer chain. 
Under ideal conditions, each molecule of such a compound becomes a branch point. 
This can be used to produce hard silicone resins. 
In a similar manner, precursors with three methyl groups can be used to limit molecular weight, since each such molecule has only one reactive site and so forms the end of a siloxane chain.

Well-defined PDMS with a low polydispersity index and high homogeneity is produced by controlled anionic ring-opening polymerization of hexamethylcyclotrisiloxane. 
Using this methodology it is possible to synthesize linear block copolymers, heteroarm star-shaped block copolymers and many other macromolecular architectures.
The polymer is manufactured in multiple viscosities, ranging from a thin pourable liquid (when n is very low), to a thick rubbery semi-solid (when n is very high). 
Polydimethylsiloxane (PDMS) molecules have quite flexible polymer backbones (or chains) due to their siloxane linkages, which are analogous to the ether linkages used to impart rubberiness to polyurethanes. 
Such flexible chains become loosely entangled when molecular weight is high, which results in PDMS' unusually high level of viscoelasticity.

Mechanical properties of Polydimethylsiloxane (PDMS)
Polydimethylsiloxane (PDMS) is viscoelastic, meaning that at long flow times (or high temperatures), it acts like a viscous liquid, similar to honey. 
However, at short flow times (or low temperatures), it acts like an elastic solid, similar to rubber. 
Viscoelasticity is a form of nonlinear elasticity that is common amongst noncrystalline polymers.
The loading and unloading of a stress-strain curve for PDMS do not coincide; rather, the amount of stress will vary based on the degree of strain, and the general rule is that increasing strain will result in greater stiffness. 

When the load itself is removed, the strain is slowly recovered (rather than instantaneously). 
This time-dependent elastic deformation results from the long-chains of the polymer. 
But the process that is described above is only relevant when cross-linking is present; when it is not, the polymer PDMS cannot shift back to the original state even when the load is removed, resulting in a permanent deformation. 
However, permanent deformation is rarely seen in PDMS, since it is almost always cured with a cross-linking agent.

If some Polydimethylsiloxane (PDMS) is left on a surface overnight (long flow time), it will flow to cover the surface and mold to any surface imperfections. 
However, if the same Polydimethylsiloxane (PDMS) is poured into a spherical mold and allowed to cure (short flow time), it will bounce like a rubber ball.
The mechanical properties of PDMS enable this polymer to conform to a diverse variety of surfaces. 
Since these properties are affected by a variety of factors, this unique polymer is relatively easy to tune.

This enables Polydimethylsiloxane (PDMS) to become a good substrate that can easily be integrated into a variety of microfluidic and microelectromechanical systems.
Specifically, the determination of mechanical properties can be decided before PDMS is cured; the uncured version allows the user to capitalize on myriad opportunities for achieving a desirable elastomer. 
Generally, the cross-linked cured version of PDMS resembles rubber in a solidified form. 
Polydimethylsiloxane (PDMS) is widely known to be easily stretched, bent, compressed in all directions.
Depending on the application and field, the user is able to tune the properties based on what is demanded.

Overall Polydimethylsiloxane (PDMS) has a low elastic modulus which enables it to be easily deformed and results in the behavior of a rubber.
Viscoelastic properties of PDMS can be more precisely measured using dynamic mechanical analysis. 
This method requires determination of the material's flow characteristics over a wide range of temperatures, flow rates, and deformations. 
Because of Polydimethylsiloxane (PDMS)'s chemical stability, it is often used as a calibration fluid for this type of experiment.
The shear modulus of PDMS varies with preparation conditions, and consequently dramatically varies in the range of 100 kPa to 3 MPa. 
The loss tangent is very low (tan δ ≪ 0.001).

Chemical compatibility of Polydimethylsiloxane (PDMS)
Polydimethylsiloxane (PDMS) is hydrophobic.
Plasma oxidation can be used to alter the surface chemistry, adding silanol (SiOH) groups to the surface. 
Atmospheric air plasma and argon plasma will work for this application. 
This treatment renders the PDMS surface hydrophilic, allowing water to wet it. 

The oxidized surface can be further functionalized by reaction with trichlorosilanes. 
After a certain amount of time, recovery of the surface's hydrophobicity is inevitable, regardless of whether the surrounding medium is vacuum, air, or water; the oxidized surface is stable in air for about 30 minutes.
Alternatively, for applications where long-term hydrophilicity is a requirement, techniques such as hydrophilic polymer grafting, surface nanostructuring, and dynamic surface modification with embedded surfactants can be of use.

Solid PDMS samples (whether surface-oxidized or not) will not allow aqueous solvents to infiltrate and swell the material. 
Thus PDMS structures can be used in combination with water and alcohol solvents without material deformation. 
However most organic solvents will diffuse into the material and cause it to swell.
Despite this, some organic solvents lead to sufficiently small swelling that they can be used with PDMS, for instance within the channels of PDMS microfluidic devices. 

The swelling ratio is roughly inversely related to the solubility parameter of the solvent. 
Diisopropylamine swells PDMS to the greatest extent; solvents such as chloroform, ether, and THF swell the material to a large extent. 
Solvents such as acetone, 1-propanol, and pyridine swell the material to a small extent. 
Alcohols and polar solvents such as methanol, glycerol and water do not swell the material appreciably.

Applications of Polydimethylsiloxane (PDMS)
Surfactants and antifoaming agents
Polydimethylsiloxane (PDMS) is a common surfactant and is a component of defoamers.
Polydimethylsiloxane (PDMS), in a modified form, is used as an herbicide penetrant and is a critical ingredient in water-repelling coatings, such as Rain-X.

Hydraulic fluids and related applications
Dimethicone is used in the active silicone fluid in automotive viscous limited slip differentials and couplings.

Soft lithography
Polydimethylsiloxane (PDMS) is commonly used as a stamp resin in the procedure of soft lithography, making it one of the most common materials used for flow delivery in microfluidics chips.
The process of soft lithography consists of creating an elastic stamp, which enables the transfer of patterns of only a few nanometers in size onto glass, silicon or polymer surfaces. 
With this type of technique, it is possible to produce devices that can be used in the areas of optic telecommunications or biomedical research. 
The stamp is produced from the normal techniques of photolithography or electron-beam lithography. 
The resolution depends on the mask used and can reach 6 nm.

The popularity of PDMS in microfluidics area is due to its excellent mechanical properties. 
Moreover, compared to other materials, it possesses superior optical properties, allowing for minimal background and autofluorescence during for fluorescent imaging.
In biomedical (or biological) microelectromechanical systems (bio-MEMS), soft lithography is used extensively for microfluidics in both organic and inorganic contexts. 
Silicon wafers are used to design channels, and PDMS is then poured over these wafers and left to harden. 
When removed, even the smallest of details is left imprinted in the PDMS. 

With this particular PDMS block, hydrophilic surface modification is conducted using plasma etching techniques. 
Plasma treatment disrupts surface silicon-oxygen bonds, and a plasma-treated glass slide is usually placed on the activated side of the PDMS (the plasma-treated, now hydrophilic side with imprints). 
Once activation wears off and bonds begin to reform, silicon-oxygen bonds are formed between the surface atoms of the glass and the surface atoms of the PDMS, and the slide becomes permanently sealed to the PDMS, thus creating a waterproof channel. 
With these devices, researchers can utilize various surface chemistry techniques for different functions creating unique lab-on-a-chip devices for rapid parallel testing.

Polydimethylsiloxane (PDMS) can be cross-linked into networks and is a commonly used system for studying the elasticity of polymer networks.
Polydimethylsiloxane (PDMS) can be directly patterned by surface-charge lithography.
Polydimethylsiloxane (PDMS) is being used in the making of synthetic gecko adhesion dry adhesive materials, to date only in laboratory test quantities.
Some flexible electronics researchers use PDMS because of its low cost, easy fabrication, flexibility, and optical transparency.
Yet, for fluorescence imaging at different wavelengths, PDMS shows least autofluorescence and is comparable to BoroFloat glass.

Stereo lithography
In stereo lithography (SLA) 3D printing, light is projected onto photocuring resin to selectively cure it. 
Some types of SLA printer are cured from the bottom of the tank of resin and therefore require the growing model to be peeled away from the base in order for each printed layer to be supplied with a fresh film of uncured resin. 
A Polydimethylsiloxane (PDMS) layer at the bottom of the tank assists this process by absorbing oxygen : the presence of oxygen adjacent to the resin prevents it adhering to the PDMS, and the optically clear PDMS permits the projected image to pass through to the resin undistorted.

Medicine and cosmetics
Activated dimethicone, a mixture of polydimethylsiloxanes and silicon dioxide (sometimes called simethicone), is often used in over-the-counter drugs as an antifoaming agent and carminative.
Polydimethylsiloxane (PDMS) has also been at least proposed for use in contact lenses.
Silicone breast implants are made out of a PDMS elastomer shell, to which fumed amorphous silica is added, encasing PDMS gel or saline solution. 
In addition, PDMS is useful as a lice or flea treatment because of its ability to trap insects.
Polydimethylsiloxane (PDMS) also works as a moisturizer that is lighter and more breathable than typical oils.

Skin
Polydimethylsiloxane (PDMS) is used variously in the cosmetic and consumer product industry as well. 
For example, Polydimethylsiloxane (PDMS) can be used in the treatment of head lice on the scalp and dimethicone is used widely in skin-moisturizing lotions where it is listed as an active ingredient whose purpose is "skin protection." 
Some cosmetic formulations use dimethicone and related siloxane polymers in concentrations of use up to 15%. 
The Cosmetic Ingredient Review's (CIR) Expert Panel, has concluded that dimethicone and related polymers are "safe as used in cosmetic formulations."

Hair
Polydimethylsiloxane (PDMS) compounds such as amodimethicone, are effective conditioners when formulated to consist of small particles and be soluble in water or alcohol/act as surfactants (especially for damaged hair), and are even more conditioning to the hair than common dimethicone and/or dimethicone copolyols.

Contact lenses
A proposed use of PDMS is contact lens cleaning. 
Its physical properties of low elastic modulus and hydrophobicity have been used to clean micro and nano pollutants from contact lens surfaces more effectively than multipurpose solution and finger rubbing; the researchers involved call the technique PoPPR (polymer on polymer pollution removal) and note that it is highly effective at removing nanoplastic that has adhered to lenses.

Flea treatment for pets
Dimethicone is the active ingredient in a liquid applied to the back of the neck of a cat or dog from a small one time use dose disposable pipette. 
The parasite becomes trapped and immobilised in the substance and thus breaks the life cycle of the insect.

Foods
Polydimethylsiloxane (PDMS) is added to many cooking oils (as an antifoaming agent) to prevent oil splatter during the cooking process. 
As a result of this, PDMS can be found in trace quantities in many fast food items such as McDonald's Chicken McNuggets, french fries, hash browns, milkshakes and smoothies and Wendy's french fries.
Under European food additive regulations, Polydimethylsiloxane (PDMS) is listed as E900.

Condom lubricant
Polydimethylsiloxane (PDMS) is widely used as a condom lubricant.

Domestic and niche uses
Many people are indirectly familiar with Polydimethylsiloxane (PDMS) because it is an important component in Silly Putty, to which PDMS imparts its characteristic viscoelastic properties.
Another toy Polydimethylsiloxane (PDMS) is used in is Kinetic Sand. 
The rubbery, vinegary-smelling silicone caulks, adhesives, and aquarium sealants are also well-known. 
PDMS is also used as a component in silicone grease and other silicone based lubricants, as well as in defoaming agents, mold release agents, damping fluids, heat transfer fluids, polishes, cosmetics, hair conditioners and other applications.
Polydimethylsiloxane (PDMS) can be used as a sorbent for the analysis of headspace (dissolved gas analysis) of food.

Polydimethylsiloxane (PDMS) is an organosiloxane that is trisiloxane in which all the hydrogens have been replaced by methyl groups.

Use and Manufacturing of Polydimethylsiloxane (PDMS)
Used as a base for extreme temperature silicone oils/fluids and as a foam suppressant in petroleum lubricating oils; [Merck Index] Used mainly to make polydimethylsiloxane (PDMS) polymers, oligomers, and mixtures; Also used to make basic chemicals, paints, coatings, adhesives, soaps, cleaning compounds, toiletries, plastics, semiconductors, and other electronic components, and in building construction, lubricants, diluents, solvents, and cosmetics; [Government of Canada - Chemicals Management Plan]

As a dielectric coolant and in solar energy installations.
As wound dressing.
Used in fire resistant transformers.
For more Uses (Complete) data for POLYDIMETHYLSILOXANES (7 total), please visit the HSDB record page.

Industry Uses of Polydimethylsiloxane (PDMS)
-Functional fluids (closed systems)
-Intermediates
-Personal Care Additive

Household Products of Polydimethylsiloxane (PDMS)
Household & Commercial/Institutional Products
Information on 27 consumer products that contain Trisiloxane in the following categories is provided:
-Auto Products
-Personal Care

Methods of Manufacturing of Polydimethylsiloxane (PDMS)
Polydimethylsiloxane oils are manufactured by the equilibrium polymerization of cyclic or linear dimethylsilicone precursors.

General Manufacturing Information
Industry Processing Sectors
-All other basic inorganic chemical manufacturing
-All other chemical product and preparation manufacturing
-Personal Care Applications

Polydimethylsiloxane (PDMS) has several useful material properties for stamping and molding. 
Polydimethylsiloxane (PDMS) provides a surface that has a low interfacial free energy, is chemically inert, has good gas permeability and good thermal stability, and is optically transparent. 
The surface properties of PDMS are also relatively easy to modify.
Polydimethylsiloxane (PDMS) is the simplest member of the silicone polymer family. 
Polydimethylsiloxane (PDMS) is formed by hydrolyzing Me2SiCl2, which is produced from high-purity SiO2 and CH2Cl2 by the Muller–Rochow reaction. 

The term “silicone” was coined by chemist F. S. Kipping in 1901.
Low–molecular weight PDMS is a liquid used in lubricants, antifoaming agents, and hydraulic fluids. 
Its use in breast implants is not as popular as it once was because of safety concerns.
At higher molecular weights, PDMS is a soft, compliant rubber or resin. 
Polydimethylsiloxane (PDMS) is used in caulks, sealants, an even Silly Putty. 
More recently, Polydimethylsiloxane (PDMS) resins have been used in soft lithography, a key process in biomedical microelectromechanical systems (bio-MEMS). 

Polydimethylsiloxane, called PDMS or dimethicone, is a polymer widely used for the fabrication and prototyping of microfluidic chips.
Polydimethylsiloxane (PDMS) is a mineral-organic polymer (a structure containing carbon and silicon) of the siloxane family (word derived from silicon, oxygen and alkane). 
Apart from microfluidics, it is used as a food additive (E900), in shampoos, and as an anti-foaming agent in beverages or in lubricating oils.
For the fabrication of microfluidic devices, Polydimethylsiloxane (liquid) mixed with a cross-linking agent is poured into a microstructured mold and heated to obtain a elastomeric replica of the mold (cross-linked).

Chemistry of Polydimethylsiloxane (PDMS)
A little bit of chemistry will help us better understand the advantages and drawbacks of PDMS for microfluidic applications.
The Polydimethylsiloxane (PDMS) empirical formula is (C2H6OSi)n and its fragmented formula is CH3[Si(CH3)2O]nSi(CH3)3, n being the number of monomers repetitions.
Depending on the size of monomers chain, the non-cross-linked PDMS may be almost liquid (low n) or semi-solid (high n). 
The siloxane bonds result in a flexible polymer chain with a high level of viscoelasticity.

Polydimethylsiloxane (PDMS) Oxidation
Polydimethylsiloxane (PDMS) oxidation using plasma changes the surface chemistry, and produces silanol terminations (SiOH) on its surface. 
This helps making the material hydrophilic for thirty minutes or so. 
This process also makes the surface resistant to the adsorption of hydrophobic and negatively-charged molecules. 
In addition, its plasma oxidation is used to functionalize the surface with trichlorosilane or to covalently bond PDMS (at the atomic scale) on an oxidized glass surface by the creation of a Si-O-Si bonds.

Whether the surface is plasma oxidized or not, Polydimethylsiloxane (PDMS) does not allow water, glycerol, methanol or ethanol infiltration and consecutive deformation. 
Thus, Polydimethylsiloxane (PDMS) is possible to use PDMS with these fluids without fear of micro-structure deformation. 
However, Polydimethylsiloxane (PDMS) deforms and swells in the presence of diisopropylamine, chloroform and ether, and also, to a lesser extent, in the presence of acetone, propanol and pyridine – therefore, PDMS is not ideal for many organic chemistry applications.
Polydimethylsiloxane (PDMS) is one of the most employed materials to mold microfluidic devices.

Polydimethylsiloxane (PDMS) is the most widely used silicon-based organic polymer, and is particularly known for its unusual rheological (or flow) properties. 
Its applications range from contact lenses and medical devices to elastomers, caulking, lubricating oils and heat resistant tiles.
PDMS is optically clear, and is generally considered to be inert, non-toxic and non-flammable. 
Polydimethylsiloxane (PDMS) is occasionally called dimethicone. 
Polydimethylsiloxane (PDMS) is one of several types of silicone oil (polymerized siloxane).

Applications of Polydimethylsiloxane (PDMS)
Many people are indirectly familiar with PDMS because it is an important (4%) component in Silly Putty, to which PDMS imparts its characteristic viscoelastic properties. 
The rubbery, vinegary-smelling silicone caulks, adhesives, and aquarium sealants are also well-known. 
Polydimethylsiloxane (PDMS) is also used as a component in silicone grease and other silicone based lubricants, as well as in defoaming agents, mold release agents, damping fluids, heat transfer fluids, polishes, cosmetics, hair conditioners and other applications. 
Polydimethylsiloxane (PDMS) has also been used as a filler fluid in breast implants, although this practice has decreased somewhat, due to safety concerns. 
Polydimethylsiloxane (PDMS) continues to be used in knuckle replacement implants, with good results.

Activated dimethicone, a mixture of polydimethylsiloxanes and silicon dioxide (sometimes called simethicone), is used in Over-the-counter drug as an anti-foaming agent and carminative.
As a food additive, it has the E number E900 and is used as an anti-foaming agent and an anti-caking agent.
Polydimethylsiloxane (PDMS) is commonly used as a stamp resin in the procedure of soft lithography, making it one of the most common materials used for flow delivery in microfluidics chips.
Polydimethylsiloxane (PDMS) can be cross-linked into networks and is a commonly used system for studying the elasticity of polymer networks.

Polydimethylsiloxane (PDMS) can be used in the treatment of head lice.
Dimethicone is also used widely in skin moisturizing lotions, listed as an active ingredient whose purpose is "skin protectant." 
Some cosmetic formulations use dimethicone and related siloxane polymers in concentrations of use up to 15%. 
The Cosmetic Ingredient Review's (CIR) Expert Panel, has concluded that dimethicone and related polymers are "safe as used in cosmetic formulations".
Polydimethylsiloxane (PDMS) is also used in analytical chemistry as a component of some types of SPME fibers.

Polydimethylsiloxane (PDMS) belongs to a group of polymeric organosilicon compounds that are referred to as silicones and is the most widely used silicon-based organic-polymer. Polydimethylsiloxane (PDMS) is particularly known for its unusual rheological or flow properties. 
Polydimethylsiloxane (PDMS) is optically clear and inert, non-toxic, and non-flammable. 
Polydimethylsiloxane (PDMS) is one of several types of silicone oil (polymerized siloxane). 

Applications of Polydimethylsiloxane (PDMS)
-Component of defoamers
-Ingredient in water-repellent coatings
-Plasticizer in silicone sealants
-Stamp resin in the procedure of soft-lithography
-Lubricant in condoms
-A component in silicone grease
-A component in heat-transfer fluids
-A component in mold-release agents
-Sorbent for the analysis of head-space

Polydimethylsiloxane (PDMS) is used in protein chromatography and affininty chromatography. 
Polydimethylsiloxane (PDMS) was used to determine that postprandial inflammatory response after ingestion of heated oils in obese persons is reduced by the presence of phenol compounds.
Clear, colorless fluid polymer useful as a stationary phase in gas chromatography and as an anti-foaming agent.
Polydimethylsiloxane (PDMS) is a colorless and transparent new polymer materials, a variety of different viscosities (5cps ~ 2million cps), the liquid from flowing easily into a thick semi-solid material. 
Polydimethylsiloxane (PDMS) has a special smoothness, softness, hydrophobicity, good chemical stability, excellent electrical insulation and resistance to high temperature. 
High flash point, low freezing point, long-term using between -50 ℃ ~ +200 ℃, low viscosity-temperature coefficient, high compression ratio, low surface tension,water-repellent moisture resistance, low heat conduction coefficient.

Polydimethylsiloxane (PDMS) is an elastomeric polymer with interesting properties for biomedical applications, including physiological indifference, excellent resistance to biodegradation, biocompatibility, chemical stability, gas permeability, good mechanical properties, excellent optical transparency and simple fabrication by replica moulding . 
Due to these characteristics, PDMS has been widely used in micropumps, catheter surfaces , dressings and bandages , microvalves , optical systems , in the in vitro study of diseases , in implants , in microfluidics and photonics. 
Moreover, soft-lithography technology has driven the use of PDMS in microelectromechanical systems (MEMS) applications and in microfluidic components . 
Soft-lithography techniques such as micro-contact printing, replica moulding, micro-transfer moulding, micro-moulding in capillaries and solvent-assisted micro-moulding usually require the use of PDMS to create an elastomeric stamp or mould that incorporates nano- and microstructures for the transfer of patterns onto a subsequent substrate.

Polydimethylsiloxane (PDMS) is the most known organosilicon rubbery polymer and its glass transition temperature is about −150 °C. 
Polydimethylsiloxane (PDMS), often referred to as “silicone rubber,” can be polymerized from different monomers by hydrolysis and anionic, cationic, emulsion, and radiation polymerization process . 
This polymer is a transparent material with high thermal and UV resistance. 
As an oligomer, PDMS is widely used as lubricants, greases, heat transfer liquids, and hydraulic liquids due to its viscoelastic properties.

Properties of Polydimethylsiloxane (PDMS):
-Very good resistance to high and low temperature,
-Good combustion resistance,
-Low surface tension,
-High compressibility,
-Absence of ageing upon exposure to atmospheric agents,
-Good oxidation resistance,
-Little change in viscosity with temperature,
-Good resistance to high and prolonged shear stress.

Polydimethylsiloxanes (PDMS) are used in many industrial products and processes and in a variety of consumer applications, such as coatings, polishes, detergents, personal care products, foods, and medicines.
Polydimethylsiloxane (PDMS) belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones. 
Polydimethylsiloxanes (PDMS) is the most widely used silicon-based organic polymer, and is particularly known for its unusual rheological (or flow) properties. 
Polydimethylsiloxanes (PDMS) is optically clear, and, in general, inert, non-toxic, and non-flammable. 
Polydimethylsiloxanes (PDMS) is also called dimethicone and is one of several types of silicone oil (polymerized siloxane). 
Its applications range from contact lenses and medical devices to elastomers; it is also present in shampoos (as dimethicone makes hair shiny and slippery), food (antifoaming agent), caulking, lubricants and heat-resistant tiles.

Polydimethylsiloxane (PDMS) is an elastomeric material with many properties well-suited for biomedical applications, resulting in its extensive use in medical devices. 
These properties include, but are not limited to, physiological inertness, biocompatibility, a high extensibility, large coefficient of thermal expansion, and chemical and thermal stability. 
Furthermore, Polydimethylsiloxane (PDMS) can be physically or chemically modified to create composite materials comprising nanomaterials such as graphene or inorganic nanoparticles, carbonaceous materials or even organic dyes. 
The incorporation of these additives into the PDMS host broadens its functional properties and improves its electrical conductivity, optical absorption, thermal conductivity, or anti-microbial properties.

Polydimethylsiloxane (PDMS) is the most widely used siliconbased organic polymer. 
Silicones are a family of synthetic polymers with a backbone composed of repeating silicon and oxygen bonds. 
In addition to the aforementioned bonds to oxygen, the silicones are bonded to other organic groups, typically methyl groups . 
The basic repeating unit of silicones is the siloxane; the most common silicone is polydimethylsiloxane. 
The presence of organic groups attached to an inorganic backbone gives silicone a combination of properties that is responsible for their use in a wide range of applications.

Polydimethylsiloxane (PDMS) belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones. 
Polydimethylsiloxane (PDMS) is the most widely used silicon-based organic polymer, and is particularly known for its unusual rheological (or flow) properties. 
Its applications range from contact lenses and medical devices to elastomers; it is present, also, in shampoos (as dimethicone makes hair shiny and slippery), caulking, lubricating oils, and heat-resistant tiles.
Polydimethylsiloxane (PDMS) is optically clear, and, in general, is considered to be inert, non-toxic and non-flammable. 
Polydimethylsiloxane (PDMS) is occasionally called dimethicone and is one of several types of silicone oil (polymerized siloxane).

Polydimethylsiloxane (PDMS), often known as dimethylpolysiloxane or dimethicone, is a silicone polymer. 
There are various uses for PDMS owing to its flexibility and characteristics.
Although Polydimethylsiloxane (PDMS) is a very good and practical solution while a small number of units are needed, industrialization and scaling up steps are hard to handle with this polymer.

Polydimethylsiloxane (PDMS) is a non-conducting, silicone-based elastomer that is of widespread interest due to its flexibility and ease of micromolding for the rapid prototyping of microdevices and systems. 
Polydimethylsiloxane (PDMS): Structure and Applications discusses the results of electric investigations of onion-like carbon (OLC)/polydimethysiloxane composites addressing very wide frequency and temperature ranges.
Several kinds of devices for the observation of the behaviour of biological cells are discussed: micro-ridges, micro-grooves, micro-markers, and micro-slits, and the methodology to make each morphology by polydimethylsiloxane is described.

First-Aid Measures of Polydimethylsiloxane (PDMS)

Inhalation:    
Move person to fresh air; if effects occur, consult a physician.

Skin:    
Wash skin with plenty of water. 
Seek first-aid or medical attentions as needed. 
If molten material comes in contact with skin, do not apply ice but cool under ice water of running stream of eater. 
DO NOT attempt to remove the material from skin. 
Removal could result in severe tissue damage. 
Seek medical attention immediately. 
Suitable emergency safety shower facility should be immediately available.

Eyes:    
Flush eyes thoroughly with water for several minutes. 
Remove contact lenses after the initial 1-2 minutes and continue flushing for several additional minutes. 
If effects occur, consult a physician, preferably an ophthalmologist.

Ingestion:    
If swallowed, seek medical attention. 
May cause gastrointestinal blockage. 
Do not give laxatives. 
Do not induce vomiting unless directed to do so by medical personnel.

Substance identity

EC / List no.: 613-156-5
CAS no.: 63148-62-9
Mol. formula:    C8H24O2Si3

Hazard classification & labelling of Polydimethylsiloxane (PDMS) 
Warning! According to the classification provided by companies to ECHA in CLP notifications this substance causes serious eye irritation.

Polydimethylsiloxane (PDMS)  indicated, in 2009, as being intended to be registered by at least one company in the EEA.
Polydimethylsiloxane (PDMS) for which classification and labeling data have been submitted to ECHA in a registration under REACH or notified by manufacturers or importers under CLP. 
Such notifications are required for hazardous substances, as such or in mixtures, as well as for all substances subject to registration, regardless of their hazard.

Synonyms:
OCTAMETHYLTRISILOXANE
107-51-7
Trisiloxane, octamethyl-
Poly(dimethylsiloxane)
Dimeticone
1,1,1,3,3,5,5,5-Octamethyltrisiloxane
dimethyl-bis(trimethylsilyloxy)silane
Dimethicone 350
63148-62-9
UNII-9G1ZW13R0G
Pentamethyl(trimethylsilyloxy)disiloxane
9G1ZW13R0G
CHEBI:9147
Dimethylbis(trimethylsilyloxy)silane
Dimethicones
Poly(dimethylsiloxane), hydroxy terminated
MFCD00084411
MFCD00134211
MFCD00148360
CCRIS 3198
Poly(dimethylsiloxane), trimethylsiloxy terminated
EINECS 203-497-4
dimeticonum
Dimeticona
Dimethylbis(trimethylsiloxy)silane
Ctamethyltrisiloxane
Dimethicone 1000
MFCD00008264
octamethyl-trisiloxane
PDMS
dimethicone macromolecule
Silicon Oil for Oil Bath
EC 203-497-4
Octamethyltrisiloxane, 98%
Trisiloxane, 1,1,1,3,3,5,5,5-octamethyl-
DSSTox_CID_20710
DSSTox_RID_79558
DSSTox_GSID_40710
SCHEMBL23459
Siliconoil Pharma 100 cSt.
Dimethyl polysiloxane, bis(trimethylsilyl)-terminated
Dow Corning High-Vacuum Grease
CHEMBL2142985
DTXSID9040710
CHEBI:31498
CXQXSVUQTKDNFP-UHFFFAOYSA-
dimethylbis(trimethylsiloxy)siliane
Polydimethylsiloxane, 1000 cSt.
alpha-(Trimethylsilyl)-omega-methylpoly(oxy(dimethylsilylene))
[(CH3)3SiO]2Si(CH3)2
Tox21_301002
CO9816
MFCD00165850
Silane, dimethylbis(trimethylsiloxy)-
AKOS015840180
ZINC169747808
Antifoam compound for anhydrous systems
FS-4459
NCGC00164100-01
NCGC00164100-02
NCGC00254904-01
CAS-107-51-7
DB-040764
FT-0631598
FT-0696355
O0257
O9816
C07261
D91850
S12475
A801717
J-001906
Poly(dimethylsiloxane), viscosity 1.0 cSt (25 C)
Q2013799
XIAMETER(R) PMX-200 Silicone Fluid 20 CS
Polydimethylsiloxane, 20,000 cSt. trimethoxysilyl terminated
Polydimethylsiloxane, extreme low volatility, viscosity 1000 cSt.
Intermediate viscosity polydimethylsiloxane antifoam emulsion, 20% active, viscosity 1500cst
Intermediate viscosity polydimethylsiloxane antifoam emulsion, 30% active, viscosity 1500cst
Polydimethylsiloxane, trimethylsiloxy terminated, reduced volatility, viscosity 20 cSt.
Intermediate viscosity polydimethylsiloxane antifoam emulsion, 10% active, viscosity 1000-2000cst
Intermediate viscosity polydimethylsiloxane antifoam emulsion, 10% active, viscosity 800-2000cst
Intermediate viscosity polydimethylsiloxane antifoam emulsion, 20% active, viscosity 1000-2000cst
Intermediate viscosity polydimethylsiloxane antifoam emulsion, 30% active, viscosity 1000-2000cst
Polydimethylsiloxane, trimethylsiloxy terminated, extreme low volatility, viscosity 12.500 cSt. 
polydimethylsiloxane (Mw > 6800 Da)
Siloxanes and Silicones, di-Me
Polydimethylsiloxanes
Baysilon
Dimethicone
DiMethyl Polysiloxane
dimethyl polysiloxane
DIMETHYL POLYSILOXANE (ME TERM)
dimethyl silicone
dimethyl silicone oil
DIMETHYL SILICONES AND SILOXANES
Dimethyl siloxane
dimethyl siloxane
Dimethyl siloxanes and silicones
dimethyl(oxo)silane
dimethyl-bis(trimethylsilyloxy)silane
Dimethylepolysiloxane
Dimethylpolysiloxane
Dimethylsilicone
dimethylsiloxane
Dimethylsiloxane trimethylsiloxane terminated
Dimethylsiloxane, trymethylsilyloxy terminated
Monomers of Siloxanes and Silicones, di-Methyl 
Polidimetylosiloksan
Poly dimethyl siloxanes
poly(dimethylsilooxane)
POLY(DIMETHYLSILOXANE)
Poly(dimethylsiloxane)
poly(dimethylsiloxane)
Polydimethyisiloxane
polydimethyl siloxane
Polydimethylsiloxan
POLYDIMETHYLSILOXANE
Polydimethylsiloxane
Polydimethylsiloxane,linear
Polydimethylsiloxanes
Polydimetylsiloxan
Polysiloxanes, di-Me
Silicon oil
Silicone antifoam 1430
Silicone Oil
Siloxane
Siloxane, dimethyl
Siloxanes
siloxanes and other silicones (polydimethylsiloxane)
SILOXANES AND SILICONES, DI-ME
Siloxanes and Silicones, di-Me
Siloxanes and Silicones, di-Me (CTS) (MAN)
Siloxanes and Silicones, di-Me(Polydimethylsiloxanes(PDMS))
Siloxanes and silicones, dimethyl
α,ω-trimethylsilyl terminated polydimethylsiloxane
Dimethylpolysiloxane
MED-360
Dimethicone
Dimethylpolysiloxane
Dimethylpolysiloxane Hydrolyzate (Silicone Oil)
KF96
Poly[oxy(dimethylsilylene)], α-[trimethylsilyl]-ω-[(trimethylsilyl)oxy]
Polydimethyisiloxane
Polydimethylsiloxan
Polydimethylsiloxane
Polydimethylsiloxane "Silicone Silbione fluids
Polydimethysiloxane Polymer
Polydimetylsiloxan
Silicone oil
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167748-54-1
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