Question

Consider a medium viscosity liquid silicon polymer: Use building blocks Me3SiCl, Me2SiCl2 and MeSiCl3.

You will need to decide what ratios to use,the procedure, what order to add them, and what conditions.

Answer 1

Silicone polymers are widely synthesized industrially from chlorosilanes by either direct hydrolysis and condensation reactions or by ring opening polymerizations. Their materials properties can be readily changed by varying the identity of the alkyl side chains and terminating groups, the molecular weight distributions, and the degrees of cross linking.

Better control of the polymerization process can be obtained if SiMe3Cl is also used in the reaction. The SiMe3Cl terminates the polymer with an SiMe3 group preventing the linear polymer chains from condensing with each other to form longer chains and with themselves to form cyclic polymers. The more SiMe3Cl used the shorter (smaller n) the polymer chain.

For the synthesis of the linear polydimethylsiloxanes we will have to use different ratios of Me3SiCl to Me2SiCl2

For the synthesis of the cross-linked polydimethylsiloxanes, different ratios of MeSiCl3 to Me2SiCl2 can be used to give materials having cross-linked polymer.

As we have to prepare medium viscosity liquid silicon polymer, so it has medium resistance in the flow.

like this we can can create a medium viscosity liquid silicon polymer