Manufacture of silicone rubber: the rate-controlling step in the overall process is typically which reaction stage?

Introduction / Context:
Silicone rubbers are polysiloxanes made via hydrolysis of organochlorosilanes to silanols, followed by condensation to siloxane backbones and subsequent crosslinking. Understanding the slowest step clarifies process control.

Concept / Approach:
Hydrolysis of chlorosilanes is often rate-limiting, dictating silanol formation which then condenses to siloxane chains. Downstream condensation/cure can be accelerated by catalysts and conditions, but initial hydrolysis governs throughput and by-product removal (HCl).

Final Answer:
Initial hydrolysis of the silicone monomer (e.g., chlorosilane to silanol)