Copolymerization of Ethylene and Fluoroalkylnorbornene Using Highly Active ansa‐(Fluorenyl)(amido)titanium‐Based Catalysts. Issue 19 (5th September 2019)

• Record Type: Journal Article
• Authors: Sun, Yanjie; Wang, Chen; Tanaka, Ryo; Shiono, Takeshi; Cai, Zhengguo
• Is Part Of: Macromolecular chemistry and physics. Volume 220:Issue 19(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-09-05
• Subjects: copolymerization -- ethylene -- fluorinated linear low‐density polyethylene -- titanium complexes; Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.201900306
• Languages: English
• ISSNs: 1022-1352

Abstract

Abstract: Fluoroalkyl‐functionalized semi‐crystalline polyolefin is obtained by the copolymerization of ethylene and 2‐nonafluorobutyl‐5‐norbornene using ansa ‐dimethylsilylene(fluorenyl)(amido)titanium complexes1a and1b as catalysts. The copolymerization proceeds with a moderate activity affording a copolymer with high fluorine content up to 5.7 mol% (22 wt%). The melting point decreases from 134 to 82 °C according to the increase of comonomer content. Observation of a single melting point of the copolymer obtained from complex1b clearly shows the uniform structure of the copolymer, whereas complex1a gives copolymer with two melting points. The number‐averaged molecular weight of the copolymer reaches over a 10 5 order of magnitude, which enables the formation of thin film via solvent casting process. Tensile moduli of these copolymers are greatly affected by both molecular weight of the copolymer and comonomer content, and almost comparable with that of low‐density linear polyethylene. Abstract : Fluoroalkyl‐functionalized semi‐crystalline polyolefin is synthesized by random copolymerization of ethylene and 2‐nonafluorobutyl‐5‐norbornene (NB‐C4 F9 ) using a titanium catalyst. A copolymer with high fluorine content and high molecular weight enough for the formation of a thin film via solvent casting process is successfully obtained. Elongation properties of the copolymer are greatly improved by the increase of comonomer content.