This article examines influence of platinum catalyst type and concentration on crosslinking kinetics of addition-cure silicone rubber. Catalyst types: Speier catalyst (chloroplatinic acid, Pt⁴⁺) requires reduction to active low-valent species, functioning as precatalyst; Karstedt catalyst (Pt⁰ with divinyltetramethyldisiloxane) directly enters catalytic cycle. Type effects: Speier shows pronounced induction period with S-shaped curing curve (slow early, accelerated later) and higher apparent activation energy; Karstedt shows no induction, high initial rate with sharp exotherm, lower activation energy.

During sintering, PTFE particles on fiberglass fabric melt above 327°C, destroying original folded-chain lamellae and particle boundaries to form an amorphous melt. Upon cooling, PTFE recrystallizes into spherulites composed of radially oriented lamellae, with crystallinity ranging 50–70%. Cooling rate determines crystal perfection: slow cooling yields higher crystallinity, larger spherulites, greater hardness; rapid quenching gives finer spherulites and improved flexibility.