Matches in SemOpenAlex for { <https://semopenalex.org/work/W2036706939> ?p ?o ?g. }
Showing items 1 to 78 of
78
with 100 items per page.
- W2036706939 endingPage "678" @default.
- W2036706939 startingPage "665" @default.
- W2036706939 abstract "A stereochemical scheme of propagation was proposed for polymerizations of vinyl and related monomers by Friedel-Crafts catalysts. For the cationic propagation proceeding via the simple carbonium ion pair, the following two factors were considered to be of primary importance in determining the steric course of propagation: (1) the conformation of the last two units of the propagating polymer segment and the direction of approach of the incoming monomer; (2) the tightness of the growing ion pair. Thus, the front-side (less hindered site) attack to the carbonium ion gives rise to a syndiotactic placement and the back-side attack an isotactic placement. The present model can satisfactorily explain the effects of substituents, catalysts, polymerization media, and polymerization temperature on the steric structure of polymers in cationic polymerization of vinyl ethers. Extension of the scheme to polymerization of the β-substituted vinyl ethers in nonpolar solvents predicts formation of the diisotactic structures consistent with the experimental result. The influences of the polymerization condition on the steric structure of polymer were studied for cationic polymerizations of α-methylstyrene at low temperatures. Highly syndiotactic polymers were obtained for homogeneous reactions in toluene-rich media. The isotactic unit increased by increasing the content of methylcyclohexane in the solvent mixture. The effect of catalysts, though insignificant in toluene-rich media, was clearly noted in methylcyclohexane-rich media, less active catalysts (e.g., SnCl4) yielding higher amounts of the isotactic unit than more active catalysts (e.g., AlCl3). These results can be readily accommodated in the present model." @default.
- W2036706939 created "2016-06-24" @default.
- W2036706939 creator A5001851209 @default.
- W2036706939 creator A5030811810 @default.
- W2036706939 date "1970-03-01" @default.
- W2036706939 modified "2023-10-18" @default.
- W2036706939 title "A proposal on the steric course of propagation in the homogeneous cationic polymerization of vinyl and related monomers" @default.
- W2036706939 doi "https://doi.org/10.1002/pol.1970.150080309" @default.
- W2036706939 hasPublicationYear "1970" @default.
- W2036706939 type Work @default.
- W2036706939 sameAs 2036706939 @default.
- W2036706939 citedByCount "31" @default.
- W2036706939 countsByYear W20367069392012 @default.
- W2036706939 countsByYear W20367069392013 @default.
- W2036706939 countsByYear W20367069392016 @default.
- W2036706939 countsByYear W20367069392019 @default.
- W2036706939 crossrefType "journal-article" @default.
- W2036706939 hasAuthorship W2036706939A5001851209 @default.
- W2036706939 hasAuthorship W2036706939A5030811810 @default.
- W2036706939 hasConcept C104818351 @default.
- W2036706939 hasConcept C111998727 @default.
- W2036706939 hasConcept C151286553 @default.
- W2036706939 hasConcept C161790260 @default.
- W2036706939 hasConcept C166940927 @default.
- W2036706939 hasConcept C167076587 @default.
- W2036706939 hasConcept C167681012 @default.
- W2036706939 hasConcept C178790620 @default.
- W2036706939 hasConcept C183882617 @default.
- W2036706939 hasConcept C185592680 @default.
- W2036706939 hasConcept C188027245 @default.
- W2036706939 hasConcept C192562407 @default.
- W2036706939 hasConcept C201194858 @default.
- W2036706939 hasConcept C2776504022 @default.
- W2036706939 hasConcept C44228677 @default.
- W2036706939 hasConcept C521977710 @default.
- W2036706939 hasConcept C58018886 @default.
- W2036706939 hasConcept C7478940 @default.
- W2036706939 hasConcept C84687054 @default.
- W2036706939 hasConceptScore W2036706939C104818351 @default.
- W2036706939 hasConceptScore W2036706939C111998727 @default.
- W2036706939 hasConceptScore W2036706939C151286553 @default.
- W2036706939 hasConceptScore W2036706939C161790260 @default.
- W2036706939 hasConceptScore W2036706939C166940927 @default.
- W2036706939 hasConceptScore W2036706939C167076587 @default.
- W2036706939 hasConceptScore W2036706939C167681012 @default.
- W2036706939 hasConceptScore W2036706939C178790620 @default.
- W2036706939 hasConceptScore W2036706939C183882617 @default.
- W2036706939 hasConceptScore W2036706939C185592680 @default.
- W2036706939 hasConceptScore W2036706939C188027245 @default.
- W2036706939 hasConceptScore W2036706939C192562407 @default.
- W2036706939 hasConceptScore W2036706939C201194858 @default.
- W2036706939 hasConceptScore W2036706939C2776504022 @default.
- W2036706939 hasConceptScore W2036706939C44228677 @default.
- W2036706939 hasConceptScore W2036706939C521977710 @default.
- W2036706939 hasConceptScore W2036706939C58018886 @default.
- W2036706939 hasConceptScore W2036706939C7478940 @default.
- W2036706939 hasConceptScore W2036706939C84687054 @default.
- W2036706939 hasIssue "3" @default.
- W2036706939 hasLocation W20367069391 @default.
- W2036706939 hasOpenAccess W2036706939 @default.
- W2036706939 hasPrimaryLocation W20367069391 @default.
- W2036706939 hasRelatedWork W2002193782 @default.
- W2036706939 hasRelatedWork W2004234090 @default.
- W2036706939 hasRelatedWork W2022832505 @default.
- W2036706939 hasRelatedWork W2029974040 @default.
- W2036706939 hasRelatedWork W2036706939 @default.
- W2036706939 hasRelatedWork W2047748017 @default.
- W2036706939 hasRelatedWork W2067303452 @default.
- W2036706939 hasRelatedWork W2080422535 @default.
- W2036706939 hasRelatedWork W2134815951 @default.
- W2036706939 hasRelatedWork W2160889206 @default.
- W2036706939 hasVolume "8" @default.
- W2036706939 isParatext "false" @default.
- W2036706939 isRetracted "false" @default.
- W2036706939 magId "2036706939" @default.
- W2036706939 workType "article" @default.