A modified cycloolefin copolymer and its preparation method and application

Abstract

The present invention provides a modified cycloolefin copolymer and a preparation method and application thereof. The raw materials for preparing the modified cycloolefin copolymer include a cycloolefin copolymer and a modifier; the modifier has an ester group and a hydroxyl group in its molecular structure; the molar ratio of the ester group to the hydroxyl group is (0.3-2):1. In the present invention, the modified cycloolefin copolymer can solve the problem that the optical products prepared by the cycloolefin copolymer in the prior art are difficult to diffuse and penetrate due to the introduced trace water, resulting in increased haze, high yellowness and low light transmittance of the optical products; at the same time, the modified cycloolefin has low water absorption, good dimensional stability, and good strength and toughness.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a modified cycloolefin copolymer and a preparation method and application thereof. Background Art

[0002] Cyclic olefin copolymer (COC for short) usually refers to an amorphous polymer formed by copolymerization of ethylene and norbornene or other cyclic monomers using a metallocene catalyst. Compared with traditional polyethylene, polypropylene, etc., cyclic olefin copolymer materials have the characteristics of high light transmittance, high chemical stability, high thermal stability, low birefringence, low hygroscopicity, low dielectric loss, and low water permeability. They are widely used in the fields of optics, packaging materials, and medical materials. Among them, the application in the optical field has the highest requirements on the various properties of the material compared to other applications.

[0003] However, the extremely low water absorption of COC materials, while bringing advantages such as a wide range of applications and dimensional stability after molding, also leads to poor water permeability of COC materials, making it difficult for trace moisture introduced into optical products prepared from it during the molding, assembly and use process to diffuse and penetrate, resulting in an increase in the haze of the optical products, thereby affecting the optical properties of the products.

[0004] Therefore, it is an urgent problem to be solved in the art to develop a cycloolefin copolymer that has low water absorption, high dimensional stability, good mechanical properties, and a certain water permeability, so that the prepared optical products have low haze and high light transmittance. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a modified cycloolefin copolymer and a preparation method and application thereof. The modified cycloolefin copolymer can solve the problem that the optical products prepared by the cycloolefin copolymer in the prior art are difficult to diffuse and penetrate due to the introduced trace water, resulting in increased haze, high yellowness and low light transmittance of the optical products; at the same time, the modified cycloolefin has low water absorption, good dimensional stability, and good strength and toughness.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a modified cycloolefin copolymer, wherein the raw materials for preparing the modified cycloolefin copolymer include a cycloolefin copolymer and a modifier; the modifier has an ester group and a hydroxyl group in its molecular structure; and the molar ratio of the ester group to the hydroxyl group is (0.3~2):1.

[0008] In the present invention, the modified cycloolefin copolymer is modified by using a modifier containing a specific functional group to make the cycloolefin copolymer material have low water absorption, high dimensional stability and good mechanical properties, and the cycloolefin copolymer has a certain water permeability, which is beneficial to reducing the haze and yellowness of optical products and improving the light transmittance of optical products.

[0009] In the present invention, the molar ratio of the ester group to the hydroxyl group is (0.3-2):1, wherein the specific value in (0.3-2) can be, for example, 0.33, 0.5, 0.52, 0.54, 0.55, 0.56, 0.58, 0.6, 0.62, 0.64, 0.66, 0.68, 0.7, 0.72, 0.74, 0.76, 0.78, 0.8, 0.82, 0.84, 0.86, 0.88, 0.9, 0.92, 0.94, 0.96, 0.98, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, etc.; preferably (0.6-1.5):1, more preferably (0.7-1.1):1.

[0010] In the present invention, the molar ratio of the ester group to the hydroxyl group is within the above range, which ensures that the modified cycloolefin copolymer material has low water absorption and high dimensional stability while having good mechanical properties, low haze and high light transmittance; if the ester group content is too little, the mechanical properties of the modified cycloolefin copolymer material deteriorate, and the water absorption and dimensional stability are slightly poor; if the ester group content is too high, the haze and yellowness of the optical product including the modified cycloolefin copolymer material increase, and the light transmittance decreases.

[0011] In the present invention, based on the content of the cycloolefin copolymer as 100 parts by weight, the content of the modifier is 0.05 to 5 parts by weight, for example, it can be 0.05 parts by weight, 0.06 parts by weight, 0.08 parts by weight, 0.1 parts by weight, 0.2 parts by weight, 0.4 parts by weight, 0.6 parts by weight, 0.8 parts by weight, 1 part by weight, 1.2 parts by weight, 1.4 parts by weight, 1.6 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.2 parts by weight, 2.4 parts by weight, 2.6 parts by weight, 2.8 parts by weight, 3 parts by weight, 3.2 parts by weight, 3.4 parts by weight, 3.6 parts by weight, 3.8 parts by weight, 4 parts by weight, 4.2 parts by weight, 4.6 parts by weight, 4.8 parts by weight, 5 parts by weight, etc.; preferably 0.5 to 4.5 parts by weight, more preferably 2 to 4 parts.

[0012] In the present invention, when the content of the modifier is within the above range, the modified cycloolefin copolymer material has good optical properties, mechanical properties, low water absorption and high dimensional stability; when the content of the modifier is too little, the optical properties and mechanical properties are poor; when the content is too much, the water absorption and dimensional stability are poor.

[0013] In the present invention, the modifier includes any one of glyceride compounds, pentaerythritol ester compounds or sorbitan ester compounds, or a combination of at least two of them.

[0014] In the present invention, the glyceride compounds include any one of glyceryl stearate compounds, glyceryl oleate compounds, glyceryl laurate compounds, glyceryl palmitate compounds, glyceryl myristate compounds, glyceryl caprate compounds or glyceryl caprylate compounds, or a combination of at least two of them.

[0015] In the present invention, the pentaerythritol ester compound includes any one of pentaerythritol stearate compounds, pentaerythritol oleate compounds, pentaerythritol laurate compounds, pentaerythritol palmitate compounds, pentaerythritol myristate compounds, pentaerythritol tridecyl ester compounds, pentaerythritol decanoate compounds, pentaerythritol nonanoate compounds or pentaerythritol octanoate compounds, or a combination of at least two thereof;

[0016] In the present invention, the sorbitan ester compound includes any one of sorbitan oleate compounds, sorbitan stearate compounds, sorbitan laurate compounds or sorbitan palmitate compounds, or a combination of at least two of them.

[0017] In the present invention, the glyceryl stearate compound includes any one of glyceryl monostearate, glyceryl distearate, triglycerol distearate, polyglyceryl-10 stearate, polyglyceryl-6 pentamethylenetetradecanoate, polyglyceryl-6 distearate, polyglyceryl-6 stearate, polyglyceryl-3 stearate, polyglyceryl-2 distearate, polyglyceryl-2 stearate, polyglyceryl-10 diisostearate, polyglyceryl-10 isostearate, polyglyceryl-3 isostearate, polyglyceryl-4 isostearate, polyglyceryl-3 diisostearate or polyglyceryl-3 triisostearate, or a combination of at least two thereof.

[0018] In the present invention, the glycerol oleate compound includes any one of glycerol monooleate, glycerol dioleate, polyglycerol-10 dioleate, polyglycerol-10 oleate, polyglycerol-8 dioleate, polyglycerol-6 dioleate, polyglycerol-3 dioleate, polyglycerol-6 oleate, polyglycerol-3 oleate, polyglycerol-2 dioleate or polyglycerol-2 oleate, or a combination of at least two thereof.

[0019] In the present invention, the glyceryl laurate compound includes any one of glyceryl monolaurate, polyglyceryl-10 laurate, polyglyceryl-6 laurate or polyglyceryl-3 laurate, or a combination of at least two thereof.

[0020] In the present invention, the glycerol palmitate compound includes any one of polyglycerol-3 palmitate, polyglycerol-10 palmitate or polyglycerol-10 dipalmitate, or a combination of at least two of them.

[0021] In the present invention, the glyceryl myristate compound includes polyglyceryl-10 myristate.

[0022] In the present invention, the glyceryl caprate compound includes any one of polyglyceryl-6 dicaprate, polyglyceryl-3 caprate, polyglyceryl-2 caprate, polyglyceryl-10 caprate or polyglyceryl-4 caprate, or a combination of at least two thereof.

[0023] In the present invention, the glyceryl caprylate compound includes any one of polyglyceryl-10 caprylate, polyglyceryl-6 caprylate, polyglyceryl-3 caprylate or polyglyceryl-2 sesquicaprylate, or a combination of at least two thereof.

[0024] In the present invention, the pentaerythritol stearate compound includes any one of pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, dipentaerythritol monostearate, dipentaerythritol distearate, dipentaerythritol tristearate, dipentaerythritol tetrastearate or dipentaerythritol pentastearate, or a combination of at least two thereof.

[0025] In the present invention, the pentaerythritol oleate compound includes any one of pentaerythritol monooleate, pentaerythritol dioleate, pentaerythritol trioleate, dipentaerythritol monooleate, dipentaerythritol dioleate, dipentaerythritol trioleate, dipentaerythritol tetraoleate or dipentaerythritol pentaoleate, or a combination of at least two thereof.

[0026] In the present invention, the pentaerythritol laurate compound includes any one of pentaerythritol monolaurate, pentaerythritol dilaurate, pentaerythritol trilaurate, dipentaerythritol monolaurate, dipentaerythritol dilaurate, dipentaerythritol trilaurate, dipentaerythritol tetralaurate or dipentaerythritol pentalaurate, or a combination of at least two thereof.

[0027] In the present invention, the pentaerythritol palmitate compound includes any one of pentaerythritol monopalmitate, pentaerythritol dipalmitate, pentaerythritol tripalmitate, dipentaerythritol monopalmitate, dipentaerythritol dipalmitate, dipentaerythritol tripalmitate, dipentaerythritol tetrapalmitate or dipentaerythritol pentapalmitate, or a combination of at least two thereof.

[0028] In the present invention, the pentaerythritol myristate compound includes any one of pentaerythritol monomyristate, pentaerythritol dimyristate, pentaerythritol trimyristate, dipentaerythritol monomyristate, dipentaerythritol dimyristate, dipentaerythritol trimyristate, dipentaerythritol tetramyristate or dipentaerythritol pentamyristate, or a combination of at least two thereof.

[0029] The pentaerythritol tridecaned ester compound includes any one of pentaerythritol mono-tridecaned ester, pentaerythritol di-tridecaned ester, pentaerythritol tri-tridecaned ester or pentaerythritol tetra-tridecaned ester, or a combination of at least two of them.

[0030] In the present invention, the pentaerythritol caprate compound includes any one of pentaerythritol monocaprate, pentaerythritol dicaprate, pentaerythritol tricaprate, dipentaerythritol monocaprate, dipentaerythritol dicaprate, dipentaerythritol tricaprate, dipentaerythritol tetracaprate or dipentaerythritol pentacaprate, or a combination of at least two thereof.

[0031] In the present invention, the pentaerythritol nonanoate compound includes any one of pentaerythritol monononanoate, pentaerythritol dinonanoate, pentaerythritol trinonanoate, dipentaerythritol monononanoate, dipentaerythritol dinonanoate, dipentaerythritol trinonanoate, dipentaerythritol tetranonanoate or dipentaerythritol pentonanoate, or a combination of at least two thereof.

[0032] In the present invention, the pentaerythritol octanoate compound includes any one of pentaerythritol monooctanoate, pentaerythritol dioctanoate, pentaerythritol trioctanoate, dipentaerythritol monooctanoate, dipentaerythritol dioctanoate, dipentaerythritol trioctanoate, dipentaerythritol tetraoctanoate or dipentaerythritol pentaoctanoate, or a combination of at least two thereof.

[0033] In the present invention, the sorbitan ester compound includes any one of sorbitan trioleate (Span 85), sorbitan sesquioleate (Span 83), sorbitan monooleate (Span 80), sorbitan tristearate (Span 65), sorbitan monostearate (Span 60), sorbitan monopalmitate (Span 40) or sorbitan monolaurate (Span 20), or a combination of at least two of them.

[0034] In the present invention, at least two modifiers are preferably compounded to obtain a modified complex having an ester group and a hydroxyl group in a specific molar ratio; the modifier includes any one or at least two of at least two glyceride compounds, at least two pentaerythritol ester compounds, at least two sorbitan ester compounds, at least one glyceride compound and at least one sorbitan ester compound, at least one glyceride compound and at least one pentaerythritol ester compound, at least one pentaerythritol ester compound and at least one sorbitan ester compound.

[0035] In the present invention, the glass transition temperature (Tg) of the cycloolefin copolymer is 120-160°C, for example, it can be 120°C, 122°C, 124°C, 125°C, 126°C, 128°C, 130°C, 132°C, 134°C, 135°C, 136°C, 138°C, 140°C, 142°C, 144°C, 146°C, 148°C, 150°C, 152°C, 154°C, 156°C, 158°C, 160°C, etc.; preferably, it is 135-152°C.

[0036] At 260°C and 2.16 kgf, the melt flow rate (MFR) of the cycloolefin copolymer is 15 to 60 g / 10 min, for example, 15 g / 10 min, 18 g / 10 min, 20 g / 10 min, 22 g / 10 min, 24 g / 10 min, 26 g / 10 min, 28 g / 10 min, 30 g / 10 min, 32 g / 10 min, 34 g / 10 min, 36 g / 10 min, 38 g / 10 min, 40 g / 10 min, 42 g / 10 min, 44 g / 10 min, 46 g / 10 min, 48 g / 10 min, 50 g / 10 min, 52 g / 10 min, 54 g / 10 min, 56 g / 10 min, 58 g / 10 min, 60 g / 10 min, etc.

[0037] In the present invention, the Tg and MFR of the cycloolefin copolymer are within the above ranges, which is beneficial to improving the optical properties of the cycloolefin copolymer material without affecting its dimensional stability.

[0038] In the present invention, the cycloolefin copolymer includes copolymerization of olefin and cycloolefin; the olefin includes but is not limited to ethylene; the cycloolefin includes but is not limited to norbornene and the like.

[0039] In the present invention, the Tg of the modified cycloolefin copolymer is ≥130°C, for example, it can be 130°C, 132°C, 134°C, 135°C, 136°C, 138°C, 140°C, 142°C, 144°C, 146°C, 148°C, 150°C, 152°C, 154°C, 156°C, 158°C, 160°C, etc.; the MFR (260°C, 2.16kgf) of the modified cycloolefin copolymer is ≥20 g / 10 min, for example, it can be 20 g / 10 min, 22 g / 10 min, 24 g / 10 min, 26 g / 10 min, 28 g / 10 min, 30 g / 10 min, 32 g / 10 min, 34 g / 10 min, 36 g / 10 min, 38 g / 10 min, 40 g / 10 min, 42 g / 10 min, 44 g / 10 min, 46 g / 10 min, 48 g / 10 min, 50 g / 10 min, 52 g / 10 min, 54 g / 10 min, 56 g / 10 min, 58 g / 10 min, 60 g / 10 min, etc.

[0040] In a second aspect, the present invention provides a method for preparing the modified cycloolefin copolymer according to the first aspect, the preparation method comprising the following steps:

[0041] The cycloolefin copolymer is mixed with a modifier and extruded to obtain the modified cycloolefin copolymer.

[0042] Preferably, the extrusion temperature is 185-220°C, for example, it may be 190°C, 195°C, 200°C, 210°C, 215°C, 215°C, 210°C, 205°C, 205°C, 205°C, 215°C, etc.

[0043] In the present invention, the mixing and extruding are carried out in a twin-screw extruder; the temperatures in different zones of the twin-screw extruder are as follows: zone one: 185-195°C; zone two: 190-200°C; zone three: 195-205°C; zone four: 205-215°C; zone five: 210-220°C; zone six: 210-220°C; zone seven: 205-215°C; zone eight: 200-210°C; zone nine: 200-210°C; zone ten: 200-210°C; zone eleven: 210-220°C.

[0044] In a third aspect, the present invention provides a molded body, wherein the material of the molded body includes the modified cycloolefin copolymer according to the first aspect.

[0045] In the present invention, the method of forming the body includes but is not limited to injection molding.

[0046] In a fourth aspect, the present invention provides an optical product, wherein the material of the optical product comprises the modified cycloolefin copolymer according to the first aspect or the molded body according to the third aspect.

[0047] In the present invention, the optical products include optical lenses, VR glasses, etc.

[0048] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The inventors have discovered the relationship between the water absorption of cycloolefin copolymers and the haze of their molded samples, and provided a solution to reduce the haze. The modified cycloolefin copolymer provided by the present invention is modified by a modifier having an ester group and a hydroxyl group, and the molar ratio of the ester group and the hydroxyl group is within a specific range, so that the material including the modified cycloolefin copolymer has low water absorption, good dimensional stability, yellowing resistance, good strength and toughness, and has low haze and high light transmittance; the light transmittance of the modified cycloolefin copolymer material is ≥90.5%, the haze is ≤0.43%, the yellowness is ≤1.81, the tensile strength is ≥49.6 MPa, the elongation at break is ≥3.4%, the impact strength is ≥5.6 J / m, the water absorption is ≤0.015%, and the dimensional change rate after water absorption is ≤0.07%. DETAILED DESCRIPTION

[0051] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0052] The materials used in the present invention can be purchased from the market or prepared by conventional methods; unless otherwise specified, the materials used in the present invention are as follows:

[0053] Cyclic olefin copolymer

[0054] COC-1: COC resin grade TAMT1340 produced by Zhejiang Tuoxin Optical New Materials Co., Ltd., with Tg of 138°C and MFR of 35 g / 10min (260°C, 2.16 kgf);

[0055] COC-2: COC resin TAMT1520 produced by Zhejiang Tuoxin Optical New Materials Co., Ltd., with a Tg of 147°C and an MFR of 19 g / 10min (260°C, 2.16 kgf);

[0056] COC-3: COC resin TAMT1455 produced by Zhejiang Tuoxie Optical New Materials Co., Ltd., with a Tg of 142°C and an MFR of 54 g / 10min (260°C, 2.16 kgf).

[0057] Example 1

[0058] The present embodiment provides a modified cycloolefin copolymer, wherein the raw materials for preparing the cycloolefin copolymer include cycloolefin copolymer COC-1 and a modifier; based on 100 parts by weight of COC-1, the content of the modifier is 3 parts by weight; the modifier includes 40 wt% of glycerol distearate and 60 wt% of Span 80; the molar ratio of ester group to hydroxyl group in the modifier is 0.55:1.

[0059] This embodiment provides a method for preparing a modified cycloolefin copolymer, which specifically comprises the following steps:

[0060] Glycerol distearate and Span 80 are mixed to obtain a composite modifier; the composite modifier is mixed with COC-1, and the modified cycloolefin copolymer is obtained by melt blending, extrusion molding, and granulation; the molding equipment is a twin-screw extruder, and the temperature intervals of zones 1 to 11 of the twin-screw extruder are 190°C, 195°C, 200°C, 210°C, 215°C, 215°C, 210°C, 205°C, 205°C, 205°C, and 215°C, respectively.

[0061] Example 2

[0062] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 1 only in that the total amount of the modifier remains unchanged, the mass ratio of glycerol distearate and Span 80 is adjusted so that the molar ratio of ester group to hydroxyl group is 0.64:1, and the other components, amounts and preparation methods are the same as those in Embodiment 1.

[0063] Example 3

[0064] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 1 only in that the total amount of the modifier remains unchanged, the mass ratio of glycerol distearate and Span 80 is adjusted so that the molar ratio of ester group to hydroxyl group is 0.76:1, and the other components, amounts and preparation methods are the same as those in Embodiment 1.

[0065] Example 4

[0066] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 1 only in that the total amount of the modifier remains unchanged, the mass ratio of glycerol distearate and Span 80 is adjusted so that the molar ratio of ester group to hydroxyl group is 1:1, and the other components, amounts and preparation methods are the same as those in Embodiment 1.

[0067] Example 5

[0068] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 1 only in that the total amount of the modifier remains unchanged, the mass ratio of glycerol distearate and Span 80 is adjusted so that the molar ratio of ester group to hydroxyl group is 1.47:1, and the other components, amounts and preparation methods are the same as those in Embodiment 1.

[0069] Example 6

[0070] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 1 only in that the total amount of the modifier remains unchanged, the mass ratio of glycerol distearate and Span 80 is adjusted so that the molar ratio of ester group to hydroxyl group is 2:1, and the other components, amounts and preparation methods are the same as those in Embodiment 1.

[0071] Example 7

[0072] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the amount of the modifier is adjusted so that the content of the modifier is 0.05 parts by weight based on 100 parts by weight of COC-1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0073] Example 8

[0074] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the amount of the modifier is adjusted so that the content of the modifier is 1 part by weight based on 100 parts by weight of COC-1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0075] Example 9

[0076] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the amount of the modifier is adjusted so that the content of the modifier is 2 parts by weight based on 100 parts by weight of COC-1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0077] Example 10

[0078] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the amount of the modifier is adjusted so that the content of the modifier is 4 parts by weight based on 100 parts by weight of COC-1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0079] Embodiment 11

[0080] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the amount of the modifier is adjusted so that the content of the modifier is 5 parts by weight based on 100 parts by weight of COC-1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0081] Example 12

[0082] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that Span 80 is replaced by glyceryl monostearate, and the total amount of the modifier is kept unchanged, and the mass ratio of glyceryl distearate to glyceryl monostearate is adjusted so that the molar ratio of the ester group to the hydroxyl group is 0.76:1. The other components, amounts and preparation methods are the same as those in Embodiment 3.

[0083] Embodiment 13

[0084] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that glyceryl distearate is replaced by glyceryl dioleate, and the total amount of the modifier is kept unchanged, and the mass ratio of Span 80 to glyceryl dioleate is adjusted so that the molar ratio of the ester group to the hydroxyl group is 0.76:1. The other components, amounts and preparation methods are the same as those in Embodiment 3.

[0085] Embodiment 14

[0086] This embodiment provides a modified cycloolefin copolymer, which is different from Example 3 only in that the modifiers are diglyceryl fatty acid and glyceryl monoglyceride, and the total amount of the modifier is ensured to remain unchanged, the mass ratio of diglyceryl fatty acid to glyceryl monoglyceride is adjusted so that the molar ratio of ester group to hydroxyl group is 0.76:1, and the other components, amounts and preparation methods are the same as those in Example 3.

[0087] Embodiment 15

[0088] This embodiment provides a modified cycloolefin copolymer, which is different from Example 3 only in that the modifiers are pentaerythritol dipalmitate and Span 60, and the total amount of the modifier is kept unchanged, and the mass ratio of pentaerythritol dipalmitate to Span 60 is adjusted so that the molar ratio of the ester group to the hydroxyl group is 0.76:1. The other components, amounts and preparation methods are the same as those in Example 3.

[0089] Example 16

[0090] This embodiment provides a modified cycloolefin copolymer, which is different from Embodiment 3 only in that the modifiers are pentaerythritol monostearate and glycerol distearate, and the total amount of the modifiers is kept unchanged, and the mass ratio of pentaerythritol monostearate to glycerol distearate is adjusted so that the molar ratio of the ester group to the hydroxyl group is 0.76:1. The other components, dosages and preparation methods are the same as those in Embodiment 3.

[0091] Embodiment 17

[0092] This embodiment provides a modified cycloolefin copolymer, which is different from Embodiment 3 only in that the modifiers are pentaerythritol monooleate and glycerol dioleate, and the total amount of the modifiers is ensured to remain unchanged, and the mass ratio of pentaerythritol monooleate to glycerol dioleate is adjusted so that the molar ratio of the ester group to the hydroxyl group is 0.76:1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0093] Embodiment 18

[0094] This embodiment provides a modified cycloolefin copolymer, which is different from Embodiment 3 only in that the total amount of the modifier remains unchanged, there is no glycerol distearate in the modifier, the molar ratio of the ester group to the hydroxyl group is 0.33:1, and the other components, amounts and preparation methods are the same as those in Embodiment 3.

[0095] Embodiment 19

[0096] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the COC-1 is replaced by an equal mass of COC-2, and the other components, amounts and preparation methods are the same as those of Embodiment 3.

[0097] Embodiment 20

[0098] This embodiment provides a modified cycloolefin copolymer, which differs from Embodiment 3 only in that the COC-1 is replaced by an equal mass of COC-3, and the other components, amounts and preparation methods are the same as those of Embodiment 3.

[0099] Embodiment 21

[0100] This comparative example provides a modified cycloolefin copolymer, which differs from Example 3 only in that the amount of the modifier is adjusted so that the content of the modifier is 8 parts by weight based on 100 parts by weight of COC-1, and the other components, amounts and preparation methods are the same as those in Example 3.

[0101] Comparative Example 1

[0102] This comparative example provides a cycloolefin copolymer, which is different from Example 3 only in that no modifier is included in the preparation raw materials, and other components, amounts and preparation methods are the same as those in Example 3.

[0103] Comparative Example 2

[0104] This comparative example provides a modified cycloolefin copolymer, which differs from Example 3 only in that the total amount of the modifier remains unchanged, glyceryl distearate and Span 80 are replaced by an equal mass of Span 65 so that the molar ratio of the ester group to the hydroxyl group is 3:1, and the other components, amounts and preparation methods are the same as those in Example 3.

[0105] Comparative Example 3

[0106] This comparative example provides a modified cycloolefin copolymer, which differs from Example 3 only in that there is no hydroxyl group in the modifier, glyceryl distearate and Span 80 are replaced by an equal mass of glyceryl tristearate, and the other components, amounts and preparation methods are the same as those in Example 3.

[0107] Comparative Example 4

[0108] This comparative example provides a modified cycloolefin copolymer, which differs from Example 3 only in that the modifiers are tristearin and 1,2,3-propanetriol, and the total amount of the modifier is kept unchanged, and the molar ratio of tristearin to 1,2,3-propanetriol is adjusted so that the molar ratio of the ester group to the hydroxyl group is 0.76:1. The other components, amounts and preparation methods are the same as those in Example 3.

[0109] Performance Testing

[0110] The cyclic olefin copolymers provided in Examples 1 to 21 and Comparative Examples 1 to 4 were injection molded, and the injection molded products were square pieces with a size of 60 mm × 60 mm × 2 mm. The temperatures of the injection screw during the injection molding process were 50°C, 260°C, 265°C, 270°C, 270°C, and 270°C, respectively, and the mold temperature was 90°C. The obtained materials were tested for the following properties.

[0111] (1) Tensile strength test: The test standard is ASTM D638-14; the test equipment is the universal testing machine GHH of Guangzhou Biaoji Packaging Design Co., Ltd.;

[0112] (2) Impact performance test: The test standard is ASTM D256-97; the test equipment is the universal testing machine GBD-B of Guangzhou Biaoji Packaging Design Co., Ltd.;

[0113] (3) Haze test: The test standard is ASTM D1003; the test equipment is the haze meter HAM-300 of Hangzhou Yuanfang Optoelectronic Information Co., Ltd.;

[0114] (4) Yellowness test: the test standard is ASTM E313-73; the test equipment is the color analyzer HACA-5000 of Hangzhou Yuanfang Optoelectronic Information Co., Ltd.;

[0115] (5) Water absorption test: the test standard is ASTM-D570-98; the test equipment is the electronic balance XPR56DR / AC of Mettler Toledo Technologies (China) Co., Ltd.;

[0116] (6) Dimensional change test after water absorption: the test standard is ASTM E313-73; the test equipment is CND-P300 of Sanfeng Precision Measuring Instrument (Shanghai) Co., Ltd.;

[0117] (7) Test of Tg of modified cyclic olefin copolymer: the test standard is ASTM D6604-00; the test equipment is DSC 3+ of Mettler Toledo Technologies (China) Co., Ltd.;

[0118] (8) MFR test of modified cycloolefin copolymer: the test standard is ISO 1133; the test equipment is Aflow melt indexer of ZwickRoell Group.

[0119] The specific test results are shown in Table 1.

[0120] Table 1

[0121]

[0122] As can be seen from Table 1, the modified cycloolefin copolymer provided by the present invention is modified by using a modifier having an ester group and a hydroxyl group to modify the cycloolefin copolymer, and the molar ratio of the ester group to the hydroxyl group is within a specific range, so that the material including the modified cycloolefin copolymer has low water absorption, good dimensional stability, yellowing resistance, good strength and toughness, and has low haze and high light transmittance. In addition, the modifier has an effect on the Tg and MFR of the cycloolefin copolymer, but the added amount is within a certain range (the content of the cycloolefin copolymer is 100 parts by weight, and the content of the modifier is 0.05-5 parts by weight), and the effect is small and will not cause the reduction of the performance of the cycloolefin copolymer itself; the light transmittance of the modified cycloolefin copolymer material is 90.5-91.5%, the haze is 0.15-0.43%, the yellowness is 1.5-1.81, the tensile strength is 49.6-58.5 MPa, the elongation at break is 3.4-5.2%, and the impact strength is 5.6-7.3 J / m, water absorption rate is 0.004~0.015%, and the dimensional change rate after water absorption is 0.01~0.07%.

[0123] Comparison of Example 3 with the comparative example shows that if the cycloolefin copolymer is not modified by a modifier having specific ester groups and hydroxyl groups, the obtained material cannot have the effects of low water absorption, high dimensional stability, good mechanical properties and low haze.

[0124] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A modified cycloolefin copolymer, characterized in that: The raw materials for preparing the modified cycloolefin copolymer include cycloolefin copolymer and a modifier; The modifier has an ester group and a hydroxyl group in its molecular structure; The molar ratio of the ester group to the hydroxyl group is (0.5-0.86):1; Based on 100 parts by weight of the cycloolefin copolymer, the content of the modifier is 1.4 to 3.8 parts by weight; The modifier includes any one or at least two of at least two glyceride compounds, at least two sorbitan ester compounds, at least one glyceride compound and at least one sorbitan ester compound.

2. The modified cycloolefin copolymer according to claim 1, characterized in that The glyceride compound includes any one of glyceryl stearate compounds, glyceryl oleate compounds, glyceryl laurate compounds, glyceryl palmitate compounds, glyceryl myristate compounds, glyceryl caprate compounds or glyceryl caprylate compounds, or a combination of at least two thereof; The sorbitan ester compound includes any one of sorbitan oleate compounds, sorbitan stearate compounds, sorbitan laurate compounds or sorbitan palmitate compounds, or a combination of at least two of them.

3. The modified cycloolefin copolymer according to claim 2, characterized in that The glyceryl stearate compound includes any one of glyceryl monostearate, glyceryl distearate, triglycerol distearate, polyglyceryl-10 stearate, polyglyceryl-6 pentamethylenetetradecanoate, polyglyceryl-6 distearate, polyglyceryl-6 stearate, polyglyceryl-3 stearate, polyglyceryl-2 distearate, polyglyceryl-2 stearate, polyglyceryl-10 diisostearate, polyglyceryl-10 isostearate, polyglyceryl-3 isostearate, polyglyceryl-4 isostearate, polyglyceryl-3 diisostearate or polyglyceryl-3 triisostearate, or a combination of at least two thereof; The glycerol oleate compound includes any one of glycerol monooleate, glycerol dioleate, polyglycerol-10 dioleate, polyglycerol-10 oleate, polyglycerol-8 dioleate, polyglycerol-6 dioleate, polyglycerol-3 dioleate, polyglycerol-6 oleate, polyglycerol-3 oleate, polyglycerol-2 dioleate or polyglycerol-2 oleate, or a combination of at least two thereof; The glyceryl laurate compound includes any one of glyceryl monolaurate, polyglyceryl-10 laurate, polyglyceryl-6 laurate or polyglyceryl-3 laurate, or a combination of at least two thereof; The glycerol palmitate compound includes any one of polyglycerol-3 palmitate, polyglycerol-10 palmitate or polyglycerol-10 dipalmitate or a combination of at least two thereof; The glyceryl myristate compound includes polyglyceryl-10 myristate; The glyceryl caprate compound includes any one of polyglyceryl-6 dicaprate, polyglyceryl-3 caprate, polyglyceryl-2 caprate, polyglyceryl-10 caprate or polyglyceryl-4 caprate, or a combination of at least two thereof; The glyceryl caprylate compound includes any one of polyglyceryl-10 caprylate, polyglyceryl-6 caprylate, polyglyceryl-3 caprylate or polyglyceryl-2 sesquicaprylate, or a combination of at least two thereof; The sorbitan ester compound includes any one of sorbitan trioleate, sorbitan sesquioleate, sorbitan monooleate, sorbitan tristearate, sorbitan monostearate, sorbitan monopalmitate or sorbitan monolaurate, or a combination of at least two thereof.

4. The modified cycloolefin copolymer according to claim 1, characterized in that The glass transition temperature of the cycloolefin copolymer is 120-160°C; At 260° C. and 2.16 kgf, the melt flow rate of the cycloolefin copolymer is 15-60 g / 10 min.

5. A method for preparing a modified cycloolefin copolymer according to any one of claims 1 to 4, characterized in that: The preparation method comprises the following steps: The cycloolefin copolymer is mixed with a modifier and extruded to obtain the modified cycloolefin copolymer.

6. The preparation method according to claim 5, characterized in that: The extrusion temperature is 185-220°C.

7. A molded body, characterized in that The material of the molded body includes the modified cycloolefin copolymer according to any one of claims 1 to 4.

8. An optical product, characterized in that: The material of the optical product comprises the modified cycloolefin copolymer according to any one of claims 1 to 4 or the molded body according to claim 7.

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