Process for producing cyclic olefin copolymer

Abstract

The present invention provides a method for producing a copolymer capable of obtaining many cyclic olefin copolymers having excellent mechanical properties and a molecular weight suitable for general molding processing with a small amount of catalyst. A method for producing a copolymer, the method comprising: in the presence of a titanocene catalyst, at least making a cyclic olefin monomer (A) derived from norbornene and an α-olefin derived from a C4-C12 α-olefin A polymerization step of polymerizing an olefin monomer (B) to obtain a copolymer, wherein the amount of the copolymer obtained in the polymerization step is 1000 g or more relative to 1 g of the titanocene catalyst, and the number average molecular weight of the copolymer is 20000 or more and Below 200000.

Description

technical field [0001] The present invention relates to a method for producing cyclic olefin copolymers. Background technique [0002] Cyclic olefin polymers and cyclic olefin copolymers (also called "COP" and "COC", etc.) have low hygroscopicity and high transparency, and are used for optical materials such as optical disc substrates, optical films, and optical fibers. Fields are represented by various uses. As a representative COC, there is a copolymer of cyclic olefin and ethylene, and the glass transition temperature of the copolymer can be changed by the copolymerization composition of cyclic olefin and ethylene, so it is possible to manufacture a glass transition temperature (Tg) higher than COP Although the copolymer can achieve a Tg exceeding 200° C., which is difficult to achieve by COP, it has a hard and brittle property, and thus has low mechanical strength, and has problems of poor handling and processability. [0003] In addition, although there are various hi...

AI Technical Summary

Problems solved by technology

However, since the polymerization method disclosed in Patent Document 1 uses a large amount of catalysts and co-catalysts, it is difficult to save resources, the cost required to obtain a copolymer is high, and the transparency of the film is affected by the catalyst and co-catalyst residues. damage

[0007] Patent Document 2 discloses a film with excellent punching properties, but its Tg is lower than 170°C

In addition, in Patent Document 2, since a catalyst and a co-catalyst are used in large quantities, there are problems in that it is difficult to achieve resource saving, the cost required to obtain a copolymer is high, and the transparency and thermal stability of the film are impaired.

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