Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

The impact of mixing and long chain branching on MWD for radical polymerization i polyethylene and polyvinyl acetate systems

Iedema P.

Prace Wydziału Inżynierii Chemicznej i Procesowej Politechniki Warszawskiej

1999

Vol. 25, z. 1-3

115-121

The impact of mixing and long chain branching on MWD for radical polymerization in Polyethylene and Polyvinyl Acetate systems is inyestigated by simulations with the rigorous distribution software package PREDICI. The intricate relationship between the concemrations of macromolecular radicals, their growth and me branching mechanism is shown to unexpected phenomena. Living chains may grow to infinity and broad, shouldered molecular weight distributions of dead chains are created. The crucial role of random scission is explained. The resulting kinetic model is applied on industrial configurations of autoclave and tubular reactors. Autoclave systems have broad MWD (polydispersity 25) which become narrower by backflow between compartments. Tubular reactors produce relatively narrow MWD (polydispersity 6), which broadens by changing the feed strategy or the chemical reactivity of chain transfer agent.