Chap._200003 - propagating free radcal sites are usually...

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propagating free radcal sites are usually deactivated by reacting each other, without external termination agent. k td k tc m n x = n+m+2 x I-(CH 2 -CH 2 ) -I I-(CH 2 -CH 2 ) -CH 2 -CH 3 + I-(CH 2 -CH 2 ) -CH=CH 2 disproportionation combination m k t : rate constand of termination = k tc + k td n I-(CH 2 -CH 2 ) -CH 2 -CH 2 * *CH 2 -CH 2 - (CH 2 -CH 2 )-I Overall, at any given reaction time, there are three type species coexisted, including monomers, growing polymer chains and final stable polymers * Four Types Initiators and Polymerization Mechanisms for Vinyl Monomers - *+ + - X X X X tr. C-CH 2 -CH C-CH 2 -CH A C-CH 2 -CH M C-CH 2 -CH M Ziegler-Natta and Metallocene Polymerization Ionic Polymerization Active site: (free radical) (carbocation) (carboanion) (carbon-metal bond)
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This note was uploaded on 10/16/2010 for the course MATSE 441 taught by Professor Chung,tze-chiang during the Fall '10 term at Pennsylvania State University, University Park.

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