Introduction to Modified Silicone Oil-Part 2

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In last article, we have introduced some types of modified silicone oil who have similarities and differences with dimethyl silicone oil. This blog we will continue to introduce other subcategories of modified silicone oil and some common properties modified silicone oil has.

Carboxyl Modified Silicone Oil

By taking advantages of carboxyl’s reactivity and adsorptive, carboxyl modified silicone oil have been applied successfully in fabric softener, polish and lubricant. The carboxyl in modified silicone oil includes –C2H4COOH, -CH2CHMeCOOH and –C10H20C00H. Different catboxyl could replace different amounts and locations then award silicone oil different properties and effects.

There are generally five ways to produce carboxyl silicone oil: Hydrogen silicone oil reacts with unsaturated carboxylic acid ester or silicone ester with the agent Pt; Low polymer siloxane with carboxyl like (HOOCC2H4Me2Si)2O, [Me(C2H4COOH)SiO]n to be balanced with (Me2SiO)4 and (Me3Si)2O; (HOOCC2H4Me2Si)2O to be reacted with (Me2SiO)4 and PhSi(OEt)3; chlorocarbonyl siloxane to be condensate with adipic acid monosodium salt; aminohydrocarbyl silicone oil to be reacted with phthalic anhydride.

Methacryloxy Modified Silicone Oil

It is due to the unsaturated group –ROCOCMe=CH2 in the methacryloxy modified silicone oil could be reacted with other organic monomers who have unsaturated keys which lead to the polymer material who have properties of siloxane and organic polymers. Or also it will lead to the matured products properties like high heating resistance, high weather resistance and transparency.

Four types of manufacturing methods are applied in today’s industrial world:

The first is to be produced by using the silicone oil who has Si-H key and CH2=CMeCOOCH2CH=CH2 to be reacted with platinum agent. It is according to the place where Si-H key is in the silicone oil, the final goods could be divided to two-ended, single-ended and side-group methacryloxy modified silicone oil.

The second is the condensation. The product could be made via HO(Me2SiO)nH and CH2=CMeCOOC3H6SiMe(OMe)2 to be reacted with acid agent.

The third method is the CH2=CMeCOOC3H6SiMe(OMe)2 to be condensate and hydrolyzed with the acid agent to get siloxane who has CH2=CMeCOOC3H6. The new one will be balanced under acid agent environment with (Me2SiO)4 and (Me3Si)2O.

The last production method is to use Me3SiOLi to lead the condensation of (Me2SiO)n to get Me3SiO(Me2SiO)nLi, then to be condensate with CH2=CMeCOOC3H6SiMe2Cl.

Chlorocarbonyl Modified Silicone Oil

Chlorocarbonyl silicone oil’s chlorine exists in the form of C-Cl chemical key and it has medium level reactivity. It could be reacted with compounds who have OH, NH2 and SH in certain conditions. It is mainly used to produce raw materials to other carbon functional silicone oil and the modifier to organic resins. The main chlorocarbonyl in today’s market are –C3H6Cl and –CH2Cl.

Fluorocarbonyl Modified Silicone Oil

To put fluorine atoms into organic high polymer compounds could lead to the enhancement of heating stability. But in polysilocane, fluorine could represent wider applications and usually occur on the γ-location of the side chain. This is because silicone represents electropositivity. If the fluoro happens at the α-location or β-location, the heating resistance will be weaker. This is why fluorocarbonyl silicone oil is more in the category of CF3CH2CH2.

Fluorocarbonyl modified silicone oil’s main target is to change the physical properties of dimethyl silicone oil, to make it contain the features like oil resistance, solvent resistance and chemical resistance. Therefore, it is due to the lubricants, defoamer, demolition agent and textile which is made of fluorocarbonyl modified silicone oil have better properties than the ones made of dimethyl silicone oil and are widely applied in aircrafts, automotive, mechanism, chemicals and textiles. For a long time, the fluorocarbonyl in silicone oil goods is CF3CH2CH2-, but the new development of silicone oil which contains long-chain fluorocarbonyl grows fast as well.

Long Chain Alkyl Modified Silicone Oil

Long Chain alkyl modified silicone oil is the product which dimethyl silicone oil’s partly methyl is replaced by long-chain alkyl group (CaH2a+1; a=2~17 and mainly 6~17).  If we see from its chemical structure, it more belongs to hydrocarbyl silicone oil but its way of production, physical properties and applications are different from hydrocarbyl silicone oil. Therefore, people prefer to categorize it into modified silicone oil.

Long-chain alkyl modified silicone oil has excellent lubricity, hydrophobic, antifouling, printability and affinity to organic materials. When use it as the lubricant oil, it has the properties like low wearing, low coefficient of friction and compatibility with adding.

Properties of Modified Silicone Oil

Modified silicone oil contains carbon functional group silicone oil and inert base modified silicone oil. Besides they keep the original physical properties from its mother silicone oil (dimethyl silicone oil) like heating resistance, cold resistance, demoulding deformation and hydrophobic, it is also due to there are new carbon functional groups or other organic alternative groups that have specific structures are put to the molecules and they could be made to different alternative groups at different places and products of different specifications. Therefore, the goods will have new physical and chemical properties.

The basic characteristics of modified silicone oil (to compare with dimethyl silicone oil) could be categorized as below:

The first is to enhance the compatibility and solubility between organic solvents and organic polymers.

The second is to be able to react with some functional groups of organic compounds, especially organic polymers and to form stable chemical key structures.

The third is that some modified silicone oil has solubility of water and alcohols.

The forth is that they could award better surface activity.

The fifth is they will not influence surface painting or coating.

The sixth is they have adsorbability.

The seventh is they have antistatic property and antifogging property.

The last one is that they could enhance lubricity, glossiness, softness, hydrophobic, oil phobic, antifouling property and demoulding deformation to a further stage.

Summary

Though modified silicone oil has some better physical & chemical properties than linear silicone oil like dimethyl silicone oil, but they are actually having their own effective applications in different industries and all of them have good commercial and industrial values.