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Copolymerization of ethene with methyl acrylate and ethyl 10‐undecenoate using a cationic palladium diimine catalyst
Author(s) -
Heinemann Johannes,
Mülhaupt Rolf,
Brinkmann Peter,
Luinstra Gerrit
Publication year - 1999
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/(sici)1521-3935(19990201)200:2<384::aid-macp384>3.0.co;2-z
Subject(s) - copolymer , polymer chemistry , cationic polymerization , branching (polymer chemistry) , methyl acrylate , monomer , ethyl acrylate , alkyl , chemistry , polymerization , catalysis , acrylate , polymer , materials science , organic chemistry
The cationic palladium catalyst [(ArN=C(Me)C(Me)N=Ar)Pd(CH 3 )(NC—CH 3 )] + BAr' 4 ‐ (Ar = 2,6‐C 6 H 3 (CH(CH 3 ) 2 ); Ar' = 3,5‐C 6 H 3 (CF 3 ) 2 ) (DMPN/borate) was applied in ethene homopolymerization as well as ethene copolymerization with polar monomers such as methyl acrylate and ethyl 10‐undecenoate. Both ethene homo‐ and copolymerization afforded amorphous, branched polyethenes with glass temperatures around –65°C and very similar high degree of branching (105 branched C/1000C), which was independent of temperature and ethene pressure. Copolymerization with polar comonomers gave polyethylene containing both alkyl and ester‐functional alkyl side chains. The ratio of both types of short chain branches was influenced by the feed concentration of polar monomer. In the presence of sterically hindered phenols (e. g., 2,6‐di‐ tert ‐butyl‐4‐methylphenol (BHT)) and tetramethylpiperidine‐ N ‐oxyl radical (TEMPO) acrylate homopolymerization was prevented. BHT addition promoted both catalyst activity and methyl acrylate incorporation significantly. Polymerization reaction, polymer microstructures and polymer properties of polar and non‐polar branched polyethenes were investigated.