Important Organic Silicone Monomers & Properties

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It is among all important kinds of organic silicone products, silicone monomers play a unique role in the whole organic silicone industry. It is important materials to some other products. However, it could also be directly used in many fields. It is also some primary forms of some silicone products. Today, we will introduce several types of organic silicone monomers and their corresponding properties.

Aryl Chlorosilane

Aryl chlorosilane is the most important organic chlorosilane monomer in industry. Its common formula is RnSiCl4-n (n=1~3). Its main types include CH3SiCl3, (CH3)2SiCl2,CH3SiHCl2,(CH3)2HSiCl,SiCl4,(CH3)3SiCl,C6H6SiCl3,(C6H6)2SiCl2,(CH3)C6H6SiCl2 and so on. It is according to the number of chlorine atoms; it will become monochlorosilane, dichlorosilane and trichlorosilane and finally becomes different organic silicone resin which has different molecular quantity.

Most methyl or phenyl aryl chlorosilane is stimulating colorless liquid. When the monomer gets contact with water in the air, it will be rapidly hydrolyzed to release HCl which will bring strong smells. When the monomer contacts skins of humans, it will be corrosive.

Most methyl or phenyl aryl chlorosilane’s relative density is over 1 and all of them are easy to be soluble into aromatic hydrocarbons, halogenated hydrocarbons and some other solvents.

It has extreme polarity Si-Cl chemical key with strong activity.

Organosilanol

Organosilanol is the important medium product of organic chlorosilane’s hydrolysis to produce organic silicone resin. Its common formula is RnSi(OH)4-n.Silanol key is the polar key and different hydrogen key could be combined between molecules, thus the boiling point is higher. At the same time, silanol base could form hydrogen key with water molecule to make silanol has some solubility in water.

When polysiloxane has been hydrolyzed, there will produce organic silanol. Silanols will automatically or forced to be condensate to polysiloxane. The reactional activity is determined by the structure of silanol and reactional condition. When Rs are the same, when the number of –OH base of silicon atom is decreasing, and the increment in number of functional groups and size, the space isolation effect of –OH base is increasing, the sequence of reactional activity of organic silanol is RSi(OH)3>R2Si(OH)2>R3SiOH.

Organoalkoxy Silane

Organoalkoxy silane monomer is another important monomer besides methyl or phenyl chlorosilane. It is made of the reaction between organic chlorosilane monomer and alcohol. Its common formula is RnSi(OR’)4-n (n=1~3). The R is methyl or phenyl while R’ is methyl or ethyl.

Methyl or phenyl ethoxysilane are mostcolorless  fragment liquid. It is stable when contact with water.

Organoyloxy Silane

Among all organoyloxy silane, the acetoxysilane has the most industrial value. Its common formula is RnSi(OOCR’)4-n (n=1~3). Its main component is acetoxy monomer, and it includes (CH3COO)2Si(CH3)2,(CH3COO)2SiCH3 and so on.

Organoyloxy silane is easy to be hydrolyzed to release acetic acid.

It is stable when being stored in the place where isolated from air. When it is exposed to the air, it will be hydrolyzed by water in air and finally produces Si-O-Si compounds.

Also, as the raw material to produce organic silicone high polymer, it could also react with organoalkoxy silane monomer to produce Si-O-Si polymers.

Organosilicon Amine

Its Si-N key is very easy to be hydrolyzed to produce silanol and organic amines. It could be used as crosslinking agents for RTVs. It could also be used to make some high polymers.

The most important compound which contains Si-N key is hexamethyldisilazane. It is a very effective chemical to make involatile silanol to become volatile silane. This reaction could also be perfectly done in low temperature with a very high conversion rate.

Methyl phenyl Dichlorosilane

Methyl phenyl dichlorosilane is one of the most important monomers to produce organic silicone macro polymers. There exist methyl and phenyl in the same silicon atom. Therefore, it contains both of some properties of methyl and phenyl to cover the shortage of only containing single functional group. It is now widely used in improving properties of organic silicone macro polymers. Its chemical properties are similar with methyl and phenyl chlorosilane.

Organosilanes with Functional Groups

This type of monomer not only contains functional groups that directly linked to silicon atoms, but also contains functional groups of hydrocarbon base that connected to silicon atoms. The examples are CH2=CHSiCl3,CH3(CH2=CH)SiCl2,CH2=CHSi(OC2H5)3,CH3(CH2=CH)Si(OC2H5)2,CF3CH2CH2(CH3)SiCl2 and NCCH2CH2CH2SiCl3.Therefore, it not only contains the reactional properties of common organic silicone monomer functional group but also has the common functional group’s properties. It is a special type of organic silicone monomer and its types and categories are continuously developed.

For organic silicone monomer which contains unsaturated groups, it has polymerization property. In the process of making organic silicone macro polymers, when bring some monomers with vinyl, it is due to the existence of vinyl unsaturated groups, it could improve the reactional activity of high polymers; When bring vinyl monomer into organic silicone polymers, we could produce LTV or organic silicone resins. The vinyl or propylene in the monomer could further be reacted for some famous organic carbon chemical reactions like Diels-Alder reaction or others.

As for Hydroxy-Substituted Organosilanes, it is due to the existence of electropositive silicon atoms, it has the properties of phenol and could reach the target of bring siloxane into organic resins.

Epoxy-substituted organosilane is the product that made by to bring epoxy into organic silane. If it relies on the reaction of epoxy, it is possible that to bring siloxane base into polymers which contains active hydrogen to improve the physical and chemical properties of the selected resins.

Summary

So, it is evident that organic silicone monomers contain a wide range of different types of silicone products and all of them could be used to make further organic silicone products. The different variety of organic silicone monomers also means there are many different types of excellent physical and chemical properties which mean they could be widely used in different industries or for special purposes. Thus, the potential market for these organic silicone monomers could be said pretty huge and it is now also one of the largest organic silicone products on the whole global markets.