Polysiloxane is a kind of polymer with repeated si-o bond, which is directly connected with organic groups on silicon atoms, where R represents organic groups, such as methyl, phenyl, etc. N is the number of organic groups connected to silicon atoms (1 ~ 3); M is the degree of aggregation (m is not less than 2).
Silicone compounds for people know as early as the 1860 s, but until the 1940 s, Eugene Dr RoChow conducted a groundbreaking work, this kind of important compounds for commercial applications. The chemical properties of siloxane enable polymer chemists to construct an accurate molecular structure using the ideal nanotechnology. The silicone polymer comes from silicon dioxide (Si02), a natural mineral that accounts for 25 percent of the earth's crust. When a carbon source exists, silicon dioxide converts to siloxane at high temperatures. The resulting metal is then crushed and injected into a fluidized bed reactor to get chlorosilane containing chlorine.
The chlorosilane is placed in water, and hydrochloric acid (HCl) is released, and a series of siloxane structures are produced by distillation and multi-step purification. The most important of these are: hexamethyldisiloxane (MM), cyclomethylsiloxane (D4) and Silanic hydrogen (si-h) compounds. These materials can be combined in a variety of ways to make important siloxane polymers.
The chemical structure of siloxane
The steps to construct the chemical structure of siloxane are the process of determining the length, the branching and the insertion of the organic groups. In terms of its chemical structure, the structure groups in the molecules are represented by the letters M (single functional group), D (two functional groups), T (three functional groups) and Q (four functional groups). M functional groups are chain terminating because they're single functional groups; D functional groups are linear increments, making the molecules bigger and more viscous. The M and D functional groups react with a siloxane fluid.
The siloxane liquid, also known as silicone or single-siloxane, is sold according to its viscosity, which is in the range of 0.65cst-1000 CST. If the product is not made of two different viscosity liquids, then the viscosity is related to the molecular weight. The difference in viscosity, tactility and elasticity is an important influence. Strictly speaking, it is a constitutive relationship.
The last operation to consider is the derivative reaction. In this step, the reactive groups of functions are added to the action steps further, generate new compounds, the hydroxyl of polydimethylsiloxane copolymer polyols reaction is such an example. In fact, a series of surface active siloxane that can be compared with a large number of standard surfactants has been developed and marketed.
The siloxane ester is an excellent example of the effect of derivation on the performance of siloxane, which is generated by polydimethylsiloxane and the recommended fatty acid esterification. A product can be generated by esterification of a group of compounds that are soluble in water, siloxane and fat in the same molecule.
Whether the siloxane product is a recipe for delight or frustration depends on how well the formulator understands the molecular structure, function, and derivation of the molecules used in the recipe. This understanding has become more important as the time for developing new products has become shorter.
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