Cycloolefin‐copolymere: Eine neue klasse transparenter thermoplaste

Abstract

Investigation of the polymerization process and property modification of metallocene-bad cycloolefin copolymers (COC) shows that this monomer-catalyst combination enables synthesis of a new class of transparent thermoplastic polymers. Metallocene catalysis offers much opportuNty to v"y the composition and microstructure of the copolymers. The breadth of the polymer spe-ctwrn which can be hrther widened by polymer modification enables many applications for this new class of thermoplastics. The key parameters that control structure and properties in the COC family are discussed in this paper. ZUSAMMENFASSUNC Untersuchungen wesentlicher Aspekte der Polymerisation und der Eigenschallsmodifikation aufMetallocen-Katalyse basierender Cycloolefin-Copolymere (COC) zeigen, dal3 mit dieser Monomer-Katalysator-Kombination eine neue Klasse transparenter Thermoplasten Prghglich gemacht wird. COC konnen mit Metallocenen in beliebiger Zusammensetzung und mit kontrollierter Mikrostruktur hergestellt werden. Die somit erreichte und durch zusittzliche Modifikationen noch enveitehare Breite des Eigenschaftsspektrums erm6glicht Vielfllltige Anwendungen dieser neuen Polymerklasse. Die wichtigsten Schliisselfaktoren i m rohstofflich-technologischen Bereich, die diese Struktur-und Eigenschaftsvielfalt ergeben, werden beispielhaft beschrieben.

Design of Efficient Molecular Catalysts for Synthesis of Cyclic Olefin Copolymers (COC) by Copolymerization of Ethylene and α-Olefins with Norbornene or Tetracyclododecene

“…The Cp'-imidazolin-2-iminato analogue exhibits remarkable catalytic activities for ethylene (co)polymerization [49][50][51], and ethylene/NBE copolymerization by CpTiCl 2 [1,3-t Bu 2 (CHN) 2 C=N] (9) afforded ultrahigh molecular weight copolymer with efficient NBE incorporation and a catalytic activity that did not decrease at 80 • C [26]; both the activity and the M n value decreased upon increasing the NBE concentration under low ethylene pressure. Although the observed activities by 9 were lower than those by 7, 9 seems to be a promising candidate as an efficient catalyst that affords high molecular weight polymers at high temperature.…”

“…Design of molecular catalysts attracts considerable attention in terms of synthesis of new polymers; recent progress in the newly designed catalysts offers several new possibilities. Certain cyclic olefin copolymers (COCs) and cyclic olefin polymers (COPs) are amorphous materials with a promising combination of high transparency in the UV-vis region along with humidityand thermal-resistance (high glass transition temperature, T g ), and extremely low water absorption (excellent water vapor barrier properties) [1][2][3][4][5][6][7]. Due to promising characteristics of COCs, these are used as (i) optical applications such as lenses, liquid crystal display light guide panels, and optical films; (ii) materials in medical and diagnostic equipment and electronic devices; and (iii) packaging applications, and many other uses [8,9].…”

Synthesis and characterization of a superhydrophobic surface from cyclic olefin copolymer

“…COC is obtained by using metallocene catalysts during polymerization of norbornene and ethylene and its various forms are used as engineering thermoplastics having properties such as high glass transition temperatures in combination with excellent transparency, low density, low birefringence, very low moisture absorption, outstanding moisture barrier effect, heat distortion resistance up to 170°C, high rigidity, strength and hardness, very good electrical insulation properties, low dielectric loss, very good melt processability / flowability and good chemical resistance to acids and alkalis and polar organic solvents, excellent biocompatibility, very good blood compatibility [10][11][12][13][14][15][16][17][18][19][20][21][22]. However, COC has some weakness in chemical resistance so that it is attacked by non-polar organic solvents such as toluene and naphtha and polar solvents such as methylene chloride.…”

“…Since the first report on the synthesis of COCs in 1991 [10], the synthesis of COCs has been the subject of a large amount of research: There are several types of commercial cyclic olefin copolymers based on different types of cyclic monomers and polymerization methods. Cyclic olefin copolymers are mainly produced by chain copolymerization of cyclic monomers such as 8,9,10-trinorborn-2-ene (norbornene) or (tetracyclododecene) with ethylene or propylene [10][11][12][13][14][15]. The scheme of the synthesis of COC from ethylene and norbonene in two steps is given in Figure 1.…”

Šezdesetgodišnjica Ziegler-Nattinih katalizatora i stereospecifičnih polimerizacija

“…staklište (T g ) im ovise o sastavu od plastomera do elastomera. 60 Velike mogućnosti metalocenskih katalizatora vidljive su na primjeru dobivanja polietilena s bimodalnom raspodjelom molnih masa, polimerizacijom etilena s dva katalitička sustava. Molekule viših molnih masa (oko 500 000 g mol ) nastaju polimerizacijom etilena u prvom reaktoru uz mali udjel viših α-olefina i difluorenil-cirkonocenskih katalizatora i sastavnica su amorfne faze.…”