Ethene Copolymerization with Trialkylsilyl Protected Polar Norbornene Derivates

Abstract

Summary: The influence of the protecting group of polar norbornene derivatives and the structure of homogenous metallocene/MAO catalyst systems on the activity and the incorporation rates during ethene copolymerization reactions were studied. By varying the structure of the protecting group a relationship between the catalyst activity and the steric demand of the protecting group could be established. For the catalyst systems tested analogous relationships between the bulkiness of the protecting groups and the polymerization activity were found. Kinetic investigations point to a reversible deactivation reaction, during which a bond between the oxygen atom of the polar norbornene derivative and the center of the active catalyst is formed, competing with the olefin coordination and the subsequent insertion. The degree of polymerization deactivation can be qualitatively judged based on a correlation between calculated structural parameters of the trialkylsilyl protected norbornene derivatives and the experimentally determined polymerization activity.image

Synthesis of ethylene and norbornene copolymer with metallocene catalysts and characteristic analysis

“…Copolymerization of ethylene and NB using homogeneous metallocene catalysts has been studied by many workers in the past several years 1–27. It remains practically important to understand how the copolymer microstructures are influenced by catalysts structure and polymerization conditions.…”

Influence of chain microstructure on ethylene–norbornene copolymer film properties

“…Cyclic olefin copolymers (COCs) are a promising type of optical materials for their excellent performance in applications. The effects of copolymer composition, sequence distribution, and molecular weight on thermal properties of COC have been studied by many groups in the past decade 1–17. However, there are few reports on the relationships between chain microstructure and optical/surface properties.…”

“…The effects of copolymer composition, sequence distribution, and molecular weight on thermal properties of COC have been studied by many groups in the past decade. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] However, there are few reports on the relationships between chain microstructure and optical/surface properties. Ou and Hsu 18 prepared COC/SiO 2 nanocomposites containing 1, 5, 10, and 15 wt % SiO 2 nanoparticles through solution blending and studied addition of SiO 2 on light transparency of composites.…”

Preparation of Polar Ethylene–Norbornene Copolymers by Metallocene Terpolymerization with Triisobutylaluminium‐Protected But‐3‐en‐1‐ol

“…To avoid the catalyst deactivation, the polar monomer needs to be protected by pre‐reaction with methylaluminoxane (MAO) or alkylaluminium 14. There are a few studies that report the copolymerization of ethylene and various polar cyclic olefins with or without norbornene 14–19. In the copolymerization of ethylene with 5‐norbornene‐2‐methanol pre‐reacted with various aluminiumalkyls and trialkylsilyls, the polar monomer contents in the copolymer were about 10 mol‐% and the obtained products were crystalline 14–17.…”

“…There are a few studies that report the copolymerization of ethylene and various polar cyclic olefins with or without norbornene 14–19. In the copolymerization of ethylene with 5‐norbornene‐2‐methanol pre‐reacted with various aluminiumalkyls and trialkylsilyls, the polar monomer contents in the copolymer were about 10 mol‐% and the obtained products were crystalline 14–17. In the terpolymerization of ethylene and norbornene with 5‐norbornene‐2‐methanol or 5‐norbornene‐2‐carboxylic acid, the resulting terpolymers were amorphous with improved total cyclic olefin content 18.…”