CN114805654A - Cycloolefin copolymer and preparation method thereof - Google Patents

Abstract

The invention provides a cycloolefin copolymer, belonging to the field of functionalized polyolefin. The copolymer has a structure shown in formula (I), wherein m and n are polymerization degrees, and m: n is more than or equal to 1.5. The invention takes a cycloolefin monomer and a-olefin with a structure of a formula (II) as polymerization monomers in an inert solvent, and the polymerization reaction is carried out in the inert solvent in the presence of a catalyst to obtain the cycloolefin copolymer with the structure of the formula (I). The adopted cycloolefin monomer has a structure shown in a formula (II), the cycloolefin monomer has an amido bond in the internal structure, a late transition metal catalyst is used, a masking agent is not added in the reaction process, the new polar group is embedded in the norbornene skeleton, and the polar group is protected by a substituent group. Compared with the common amide copolymer, the molecular weight of the copolymer is obviously improved, and higher insertion rate can be maintained. The molecular weight of the copolymer and the insertion rate of the polar monomer can be regulated and controlled by regulating and controlling the feeding ratio of the polar monomer; different catalysts are used to regulate the active molecular weight of the polymer, and the like. The experimental results show that: the insertion rate is 0.24-30.1%, the glass transition temperature is 23-196 ℃, and the elongation at break is 1.9-411%.

Description

A kind of cycloolefin copolymer and preparation method thereof

technical field

The invention belongs to the field of functionalized polyolefins, and in particular relates to a cyclic olefin copolymer and a preparation method thereof.

Background technique

Cyclic olefin copolymers (COCs) are generally prepared by addition copolymerization of α-olefins and cyclic olefins, which have advantages such as low density, high transparency, good thermal stability, high optical refractive index and chemical resistance. Strong and other excellent performance. Since it was first synthesized in the 1990s, COC has become one of the important engineering plastics and is used in heat-resistant and optical materials. When the glass transition temperature (Tg) of COC is greater than 130°C, the obtained COC has higher practical value. In order to obtain COC with Tg greater than 130°C, the prior art improves the insertion rate of cyclic olefins in the copolymer to improve the The glass transition temperature of the obtained cyclic olefin copolymer, for example, the copolymer of ethylene-norbornene (NB) disclosed in the prior art, when the insertion rate of norbornene exceeds 50 mol%, a cyclic olefin with Tg greater than 150° C. can be obtained Copolymers. However, at a high cycloolefin insertion rate, the obtained COC molecules are more rigid, making the copolymers more brittle, which hinders the application of COCs. At present, Japan's Mitsui Chemicals Corporation (Mitsui) and Japan's Polyplastics (Polyplastics) has launched a commercial COC, trade names were APEL and Topas.

The research results disclosed in the prior art show that COC can be applied in the optical field, medical field and low-dielectric material field, and the development direction has begun to shift to high-end applicable materials. However, most of the existing technologies are usually prepared from α-olefin and non-polar cyclic olefin monomers, which greatly limits the application of this type of polyolefin materials; while α-olefin and cyclic olefin monomers with polar groups The bulk preparation usually has poor performance in terms of activity and insertion rate, resulting in the lack of application of this type of functional materials.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a cyclic olefin copolymer and a preparation method thereof. Since the cyclic olefin copolymer provided by the present invention has polar groups embedded in the skeleton, the poisoning of the catalyst by the polar groups is reduced, and the cyclic olefin copolymer can be improved. The insertion ratio and polymerization activity of polar groups in the copolymers, and the polar groups can undergo ring-opening reactions under different conditions, which enriches the application scenarios of the copolymers.

The present invention first provides a cyclic olefin copolymer, which has the structure shown in formula (I):

Where m and n are the degree of polymerization, m:n≥1.5;

R ₁ and R ₂ are independent hydrogen or saturated aliphatic hydrocarbon groups with 1-10 carbon atoms; R ₃ is alkyl, aryl, halogen, alkoxy, CF ₃ , NO ₂ , N(CH ₃ ) ₂ , Cbz (benzyloxycarbonyl), Boc (tert-butoxycarbonyl), Fmoc (fluorenemethoxycarbonyl), Alloc (allyloxycarbonyl), Teoc (trimethylsilylethoxycarbonyl), Pht (phthaloyl), Tos (p-toluenesulfonyl), Tfa (trifluoroacetyl), Trt (trityl), Dmb (2,4-dimethoxybenzyl), PMB (p-methyl) oxybenzyl) or Bn (benzyl).

Preferably, 20≥m:n≥2.3.

Preferably, the R ₁ and R ₂ are independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or hydrogen.

Preferably, the cyclic olefin copolymer specifically includes the following polymers:

The present invention also provides a preparation method of the cyclic olefin copolymer described in the above technical scheme, comprising the following steps:

In an inert solvent, the cycloolefin monomer having the structure of formula (II) and α-olefin are polymerized in the presence of a catalyst to obtain a cycloolefin copolymer having the structure of formula (I);

In formula (I), m and n are the degree of polymerization, and m:n≥1.5;

R ₁ and R ₂ are independent hydrogen or saturated aliphatic hydrocarbon groups with 1-10 carbon atoms; R ₃ is alkyl, aryl, halogen, alkoxy, CF ₃ , NO ₂ , N(CH ₃ ) ₂ , Cbz (benzyloxycarbonyl), Boc (tert-butoxycarbonyl), Fmoc (fluorenemethoxycarbonyl), Alloc (allyloxycarbonyl), Teoc (trimethylsilylethoxycarbonyl), Pht (phthaloyl), Tos (p-toluenesulfonyl), Tfa (trifluoroacetyl), Trt (trityl), Dmb (2,4-dimethoxybenzyl), PMB (p-methyl) oxybenzyl) or Bn (benzyl).

Preferably, the α-olefin is ethylene, propylene, 1-butene, isobutene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2- - methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene or 2-ethyl-1-butene;

Preferably, the catalyst is a phosphine sulfonic acid palladium phosphine phenol nickel catalyst.

Preferably, the catalysts include di-o-methoxyphenyl substituted phosphine sulfonate palladium catalysts, 2-(2,6-dimethoxybenzene) phenyl and phenyl substituted phosphine sulfonate palladium catalysts, bicyclic Hexyl substituted phosphine sulfonate palladium catalyst, di-tert-butyl substituted phosphine sulfonate palladium catalyst, tert-butyl and mes-trimethoxyphenyl substituted phosphine sulfonate palladium catalyst, 2-(2,6-dimethoxy Benzene) phenyl and phenyl substituted nickel phosphine phenoxide catalysts.

Preferably, the molar ratio of the catalyst to the cycloolefin monomer having the structure of formula (II) is 1:200-2400; the molar ratio of the a-olefin to the cycloolefin monomer having the structure of formula (II) The molar ratio is (2.3-20):1.

Preferably, the temperature of the polymerization reaction is 30°C-100°C, and the time of the polymerization reaction is 30 minutes-240 minutes.

The beneficial effects of the present invention

The present invention provides a cyclic olefin copolymer having the structure of formula (I), wherein m and n are the degree of polymerization, and m:n≥1.5. In the present invention, the cycloolefin monomer having the structure of formula (II) and α-olefin are polymerized monomers in an inert solvent, and they are polymerized in an inert solvent in the presence of a catalyst to obtain a compound having the formula (I) Structure of cyclic olefin copolymers. The cycloolefin monomer used in the present invention has the structure of formula (II), which is a cycloolefin monomer with an amide bond in its internal structure, uses a late transition metal catalyst, and does not add a masking agent in the reaction process. Monomers with groups embedded in norbornene skeleton, polar groups are protected by substituents. Compared with the common amide copolymer, the molecular weight of the copolymer is significantly improved, and the insertion rate can be maintained high. By regulating the feeding ratio of polar monomers, the molecular weight of the copolymer and the insertion rate of polar monomers can be regulated; the active molecular weight of the polymer can be regulated by using different catalysts. The experimental results show that the insertion rate is 0.24%-30.1%, the glass transition temperature is 23℃-196℃, and the elongation at break is 1.9%-411%.

At the same time, the cyclic olefin copolymer obtained by the present invention has higher transparency and better molecular weight distribution, and in the preparation method of the cyclic olefin copolymer provided by the present invention, the polymerization reaction of the cyclic olefin monomer and α-olefin has higher reactivity. The experimental results show that the number average molecular weight of the cyclic olefin copolymer obtained by the present invention is 1.3kg/mol-105.6kg/mol, and the molecular weight distribution index is 1.42-3.08; the light transmittance of the cyclic olefin copolymer provided by the present invention in the visible light region >80%; the reactivity is 1.5-41.4×10 ⁴ g.mol ^-1 h ^-1 .

Moreover, the cyclic olefin copolymer obtained by the present invention can be hydrolyzed under different conditions due to the lactam bond on the main chain structure, and can prepare a water-soluble polymer after being hydrolyzed under an acidic condition, which can be used as a novel antibacterial water-soluble polymer.

Description of drawings

FIG. 1 is a ¹ H-NMR spectrum diagram of the cycloolefin monomer 13 of Example 2 of the present invention.

FIG. 2 is a nuclear magnetic ¹ H-NMR spectrum of the copolymer of ethylene and cycloolefin monomer 13 in Example 19 of the present invention.

3 is a tensile fracture curve diagram of the copolymer of ethylene and cycloolefin monomer 13 in Example 8 of the present invention.

FIG. 4 is a visible see-through curve diagram of the copolymer of ethylene and cycloolefin monomer 13 of Example 24 of the present invention.

Detailed ways

The present invention provides a cyclic olefin copolymer, which has the structure of formula (I):

Wherein m and n are the degree of polymerization, m:n≥1.5; preferably 2.3≤m:n≤20, more preferably 3≤m:n≤15;

R ₁ and R ₂ are independently hydrogen or saturated aliphatic hydrocarbon groups with 1-10 carbon atoms; preferably independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or hydrogen;

R ₃ is an alkyl group containing 20 or less carbons, an aryl group, a halogen, an alkoxy group, CF ₃ , NO ₂ , N(CH ₃ ) ₂ , Cbz (benzyloxycarbonyl), Boc (tert-butoxycarbonyl), Fmoc (Fluorenemethoxycarbonyl), Alloc (allyloxycarbonyl), Teoc (trimethylsilylethoxycarbonyl), Pht (phthaloyl), Tos (p-toluenesulfonyl), Tfa (trifluoroacetyl) , Trt (trityl), Dmb (2,4-dimethoxybenzyl), PMB (p-methoxybenzyl) or Bn (benzyl).

According to the present invention, the cyclic olefin copolymer preferably includes the following polymers:

The weight average molecular weight of the cyclic olefin copolymer obtained by the present invention is preferably 2.8 kg/mol to 215.3 kg/mol, more preferably 13.6 kg/mol to 137.6 kg/mol. In the cyclic olefin copolymer provided by the present invention, since the molecular structure contains amide bonds, the flexibility of the polymer is correspondingly improved, the proportion of polymerized units of α-olefin is reduced, the toughness of the polymer is improved, and this type of cyclic olefin copolymer is improved. The application type of olefin polymer polymer is further improved.

The cycloolefin monomer in the cycloolefin copolymer provided by the present invention has the structure of formula (II), which is a cycloolefin monomer containing an amide bond in the molecular structure. During the copolymerization with α-olefin, due to the internal polarity of the molecule The effect of the group increases the content of α-olefin in the cyclic olefin copolymer chain, which reduces the rigidity of the polymer chain and strengthens the entanglement between the chains, thereby obtaining a cyclic olefin copolymer with higher flexibility. Under the lower insertion rate of the cycloolefin monomer having the structure of formula (II), the obtained cycloolefin copolymer has a higher glass transition temperature and has higher practical value. The experimental results show that, in the cyclic olefin copolymer provided by the present invention, the insertion rate of the cyclic olefin monomer having the structure of formula (II) can be adjusted between 0.24% and 30.1%, and the glass transition temperature can reach 196°C; When the glass transition temperature of the cycloolefin copolymer is 74℃, its elongation at break is 11%, the tensile strength is 60MPa, and the tensile modulus is 630MPa. A series of new molecules containing amide bonds are successfully obtained. High-performance cyclic olefin copolymer with polar-like groups.

The present invention provides a preparation method of the cyclic olefin copolymer described in the above technical scheme, comprising the following steps:

In an inert solvent, the cycloolefin monomer having the structure of formula (II) and α-olefin are polymerized monomers, and they are polymerized in the inert solvent in the presence of a catalyst to obtain a compound having the structure of formula (I). Cyclic olefin copolymer;

In formula (I), m and n are the degree of polymerization, and m:n≥1.5;

R ₁ and R ₂ are independent hydrogen or saturated aliphatic hydrocarbon groups with 1-10 carbon atoms; R ₃ is alkyl, aryl, halogen, alkoxy, CF ₃ , NO ₂ , N(CH ₃ ) ₂ , Cbz (benzyloxycarbonyl), Boc (tert-butoxycarbonyl), Fmoc (fluorenemethoxycarbonyl), Alloc (allyloxycarbonyl), Teoc (trimethylsilylethoxycarbonyl), Pht (phthaloyl), Tos (p-toluenesulfonyl), Tfa (trifluoroacetyl), Trt (trityl), Dmb (2,4-dimethoxybenzyl), PMB (p-methyl) oxybenzyl) or Bn (benzyl).

The preparation method of the cyclic olefin copolymer provided by the present invention is carried out in an inert solvent, and the inert solvent is preferably a linear hydrocarbon compound, a cyclic hydrocarbon compound or an aromatic hydrocarbon compound, more preferably a benzene compound, and most preferably toluene.

The cycloolefin monomer having the structure of formula (II) according to the present invention, the structural formula is preferably shown in 1-25:

The present invention has no particular limitation on the source of the cycloolefin monomer having the structure of formula (II), which can be a commercial product or a self-made product. The present invention has no particular limitation on the preparation method of the cycloolefin monomer having the structure of formula (II). In the present invention, the cycloolefin monomer having the structure of formula (II) is preferably prepared according to the following reaction scheme.

According to the present invention, the catalyst is a phosphine sulfonate palladium-nickel catalyst, preferably as shown in the following figure: Pd1 (bis-o-methoxyphenyl substituted phosphine sulfonate palladium catalyst), Pd2 (2-(2, 6-dimethoxybenzene) phenyl and phenyl substituted phosphine sulfonic acid palladium catalyst), Pd3 (dicyclohexyl substituted phosphine sulfonic acid palladium catalyst), Pd4 (bis-tert-butyl substituted phosphine sulfonic acid palladium catalyst), Pd5 (tert-butyl and mes-trimethoxyphenyl substituted phosphine sulfonate palladium catalyst), Ni1 (2-(2,6-dimethoxybenzene)phenyl and phenyl substituted nickel phosphine phenol catalyst). The specific structure is as follows:

The present invention preferably provides a cycloolefin monomer solution having the structure of formula (II) and a catalyst solution dissolved in an inert solvent, and adding the cycloolefin monomer solution having the formula (II) structure, the catalyst solution and the α-olefin into the inert solvent In the solvent, after carrying out the polymerization reaction, the cycloolefin copolymer having the structure of formula (I) is obtained. In the present invention, the a-olefin is preferably ethylene, propylene, 1-butene, isobutene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1- Hexene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-ethyl-1-butene, more preferably ethylene, propylene, 1-Butene isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, most preferably ethylene; The molar ratio of the cycloolefin monomer having the structure of formula (II) is preferably (2.3-20): 1, more preferably (3-15): 1; the catalyst and the cycloolefin monomer having the structure of formula (II) The molar ratio of the body is preferably 1:200-2400, more preferably 1:400-2000. In the present invention, when the α-olefin is ethylene, since ethylene is in a gaseous state, the present invention preferably fills the reaction solution with ethylene gas, and continuously feeds ethylene gas into the reactor, maintaining the pressure of ethylene preferably as 1 atmosphere to 20 atmospheres, more preferably 4 atmospheres to 8 atmospheres;

In the process of carrying out the polymerization reaction, the cyclic olefin monomer with the structure of formula (II) also has an amide structure on its backbone. Due to the influence of polar groups, under the lower insertion rate of the cyclic olefin monomer, A cyclic olefin copolymer with a higher glass transition temperature is obtained, which has the structure of formula (I), and as the proportion of flexible α-olefin units in the copolymer increases, the rigidity of the obtained cyclic olefin copolymer chain is reduced, and the chain The entanglement between them is enhanced, thereby improving the tear resistance of the cycloolefin copolymer and improving its brittleness. Further, in the present invention, the palladium phosphorus sulfonate catalyst is used as the main catalyst, and in the process of carrying out the polymerization reaction, the main catalyst has good tolerance to polar groups, so that it has excellent copolymerization catalytic ability, and promotes The copolymerization reaction of the cycloolefin monomer with the structure of formula (II) and the olefin makes the polymerization reaction of the present invention have higher reactivity.

After the polymerization reaction is completed, the present invention preferably performs post-treatment on the reaction solution obtained by the polymerization reaction, specifically

In the present invention, the reaction solution can be mixed with an ethanol solution of hydrochloric acid to terminate the growth of the polymer chain to obtain a reaction product; the reaction product is subjected to solid-liquid separation and then dried to obtain a cyclic olefin copolymer. In the present invention, the method for terminating the growth of the polymerization chain is not particularly limited, and the above-mentioned method of mixing the reaction solution with the ethanolic solution of hydrochloric acid can be used, and the volume fraction of the ethanolic solution of hydrochloric acid is preferably 5% to 15%; the present invention The reaction product is preferably subjected to solid-liquid separation by means of filtration, and the filtered product is washed. In the present invention, the washing reagent is preferably acetone, and the washing times are preferably 2 times; The invention does not have any special restrictions on the drying method, and the drying technical solution well-known to those skilled in the art can be used. In the present invention, the drying is vacuum drying, and the drying temperature is 50°C to 80°C, The drying time is preferably 16 hours to 24 hours.

After obtaining the cyclic olefin copolymer, the present invention performs structural identification and performance test on the cyclic olefin copolymer,

The specific process is as follows:

The present invention performs nuclear magnetic resonance (NMR) detection on the obtained cyclic olefin copolymer, including ¹ H-NMR spectrum, ¹³ C NMR spectrum and DEPT spectrum, and the results show that the cyclic olefin copolymer provided by the present invention has the structure of formula (I), And the insertion rate of the cycloolefin monomer with the structure of formula (II) is between 0.24 mol% and 30.1 mol%, the insertion rate of the cycloolefin monomer with the structure of formula (II) is reduced, and the resulting cycloolefin copolymerization is reduced. the rigidity of the material, thereby improving the tear resistance of the cycloolefin copolymer;

The present invention carries out a tensile test on the obtained cyclic olefin copolymer, and the results show that the obtained cyclic olefin copolymer

The elongation at break of the copolymer is between 1.9% and 411%, the tensile strength is between 4.8MPa and 60MPa, and the tensile modulus is between 276MPa and 630MPa, which shows that the cyclic olefin copolymer provided by the present invention has higher The tensile properties of the product have been improved, and its tear resistance has been improved, so that its brittleness has been significantly improved;

The present invention adopts differential scanning calorimetry (DSC) to measure the glass transition temperature of the obtained cyclic olefin copolymer, and the results show that the glass transition temperature of the cyclic olefin copolymer provided by the present invention can reach 196° C. The invention prepares the cyclic olefin copolymer with higher glass transition temperature and improved brittleness, and the obtained cyclic olefin copolymer has high practicability;

The present invention determines the molecular weight of the cyclic olefin copolymer, and the results show that the cyclic olefin copolymer prepared in the examples of the present invention

The weight-average molecular weight of the polymer is 2.8kg/mol-215.3kg/mol, the molecular weight distribution index is 1.42-3.08, and it has good molecular weight adjustability; the invention measures the light transmittance of the cyclic olefin copolymer, and the results show that, The cyclic olefin copolymer provided by the invention has high transparency, and the light transmittance in the visible light region is more than 80%.

In order to further illustrate the present invention, the cyclic olefin copolymer provided by the present invention and its preparation method are described in detail below with reference to the examples, but they should not be construed as limiting the protection scope of the present invention.

Example 1

Preparation process of cycloolefin monomer 2

Combine 2-azabicyclo[2.2.1]hept-5-en-3-one (10.0 g, 91.7 mmol), iodomethane (15.6 g, 109.6 mmol) and 4-(dimethylamino)pyridine (1.1 g, 9.0 mmol) was added to dichloromethane (250 ml). Stir at room temperature for about 24 hours. The solvent was removed by rotary evaporation and the crude product was purified by silica gel chromatography eluting with a gradient of 0-5% ethyl acetate/hexanes to give 2 (10.2 g, 90%) as a colorless oily liquid.

¹ H NMR (500MHz, 298K, CDCl ₃ , 7.26ppm): δ=6.63 (dd, 1H), 6.43–6.33 (m, 1H), 3.92–3.85 (m, 1H), 3.06–2.99 (m, 1H) ), 2.40(s, 3H), 2.08–2.01(m, 1H), 1.91–1.83(m, 1H).

Example 2

Preparation process of cycloolefin monomer 13

Combine 2-azabicyclo[2.2.1]hept-5-en-3-one (10.0 g, 91.7 mmol), di-tert-butyl dicarbonate (23.9 g, 109.6 mmol) and 4-(dimethylamino)pyridine (1.1 g, 9.0 mmol) was added to dichloromethane (250 ml). Stir at room temperature for about 24 hours. The solvent was removed by rotary evaporation and the crude product was purified by silica gel chromatography eluting with a gradient of 0-30% ethyl acetate/hexanes to give monomer 13 (18.2 g, 95%) as a white solid.

¹ H NMR (500MHz, 298K, CDCl ₃ , 7.26ppm): δ=6.72 (dd, 1H), 6.56–6.41 (m, 1H), 4.86–4.70 (m, 1H), 3.26–3.12 (m, 1H) ), 2.23–2.10 (m, 1H), 2.05–1.90 (m, 1H), 1.31 (s, 9H, t-Bu). As shown in Figure 1.

Example 3

Preparation of Cyclic Olefin Copolymers

First, the 75 mL glass pressure reactor connected to the gas line was vacuum dried at 90 °C for 1 h. Then 23 mL of toluene and 0.42 g of comonomer 13 prepared in Example 2 were added to the reactor under an inert atmosphere, and then 10.0 μmol of Pd1 catalyst was dissolved in 2 mL of dichloromethane and injected into the polymerization system through a syringe. Under rapid stirring (750 rpm), ethylene was passed in and kept at 8 bar. After 2 h, the pressure reactor was evacuated, 200 mL of hydrochloric acid and ethanol were added to quench the polymerization reaction, the polymer was filtered, and dried in a vacuum oven to constant weight to obtain 3.9 g of a polymer.

Example 4-12 Effect of monomer concentration on the copolymerization of ethylene and polar cycloolefin monomers catalyzed by late transition metal catalysts

The 75 mL glass pressure reactor connected to the gas line was first vacuum dried at 90 °C for at least 1 h. Then 23 mL of toluene and the specified amount of comonomer 13 or 2 were added to the reactor under an inert atmosphere, and then 10.0 μmol of Pd1 catalyst was dissolved in 2 mL of dichloromethane and injected into the polymerization system by syringe. Under rapid stirring (750 rpm), ethylene was passed in and kept at 8 bar. After 2 h, the pressure reactor was evacuated, 200 mL of hydrochloric acid ethanol was added to quench the polymerization reaction, and the polymer was filtered and dried in a vacuum oven to constant weight. The specific reaction conditions and results are shown in Table 1.

Table 1. Effects of reaction conditions on copolymerization of polar monomers of ethylene catalyzed by late transition metal catalysts

Note: All data are based on at least two parallel experiments (unless otherwise stated). Activity: in units of 10 ⁴ gmol ^-1 h ^-1 . M _w , M _w / _Mn : weight average molecular weight and polymer dispersibility index, respectively, measured by GPC in 1,2,4-trichlorobenzene at 150°C, relative to a polystyrene standard. The degree of branching = the number of branches per 1000 carbons, measured by hydrogen nuclear magnetic resonance spectroscopy, and the transmittance is the transmittance at a wavelength of 400 nm.

Examples 3-9 used comonomer 13 and examples 10-12 used comonomer 2.

Table 1 Polymerization data Conclusion: With the increase of monomer concentration, the polymer insertion rate gradually increases, and the polymer molecular weight also increases gradually. When the concentration is 1.0M, a copolymer of monomer 13 and ethylene with a molecular weight of 58,600 and an insertion rate of 20% can be obtained. When the concentration is 0.4-0.5M, the molecular weight of the polymer changes abruptly. The tensile fracture curve of the copolymer of ethylene and cyclic olefin monomer 13 in Example 8 is shown in FIG. 3 .

Example 13-16 Effect of reaction time on the copolymerization of ethylene and polar cycloolefin monomers catalyzed by late transition metal catalysts

The 75 mL glass pressure reactor connected to the gas line was first vacuum dried at 90 °C for at least 1 h. Then 23 mL of toluene and the specified amount of comonomer 13 were added to the reactor under an inert atmosphere, and then 10.0 μmol of Pd1 catalyst was dissolved in 2 mL of dichloromethane and injected into the polymerization system by syringe. Under rapid stirring (750 rpm), ethylene was passed in and kept at 8 bar. After a specified time, the pressure reactor was evacuated, 200 mL of hydrochloric acid ethanol was added to quench the polymerization, and the polymer was filtered and dried to constant weight in a vacuum oven. The specific reaction conditions and results are shown in Table 2.

Table 2. Effect of reaction time on copolymerization of polar monomers of ethylene catalyzed by late transition metal catalysts

Note: All data are based on at least two parallel experiments (unless otherwise stated). Activity: in units of 10 ⁴ gmol ^-1 h ^-1 . M _w , M _w / _Mn : weight average molecular weight and polymer dispersibility index, respectively, measured by GPC in 1,2,4-trichlorobenzene at 150°C, relative to a polystyrene standard. The degree of branching = the number of branches per 1000 carbons, as determined by proton NMR.

Table 2 Polymerization data Conclusion: As the monomer concentration increases, the polymer insertion rate increases gradually, and the polymer molecular weight also increases gradually. As the polymerization time increases, the yield increases, but the comonomer insertion rate decreases.

Example 17-19 The effect of ethylene pressure on the copolymerization of ethylene and polar cyclic olefin monomers catalyzed by late transition metal catalysts

The 75 mL glass pressure reactor connected to the gas line was first vacuum dried at 90 °C for at least 1 h. Then 23 mL of toluene and the specified amount of comonomer 13 were added to the reactor under an inert atmosphere, and then 10.0 μmol of Pd1 catalyst was dissolved in 2 mL of dichloromethane and injected into the polymerization system by syringe. Under rapid stirring (750 rpm), ethylene was introduced and maintained at the specified pressure. After a specified time, the pressure reactor was evacuated, 200 mL of hydrochloric acid in ethanol was added to quench the polymerization, and the polymer was filtered and dried to constant weight in a vacuum oven. The specific reaction conditions and results are shown in Table 3.

Table 3. Effect of ethylene pressure on copolymerization of polar monomers catalyzed by late transition metal catalysts

Note: All data are based on at least two parallel experiments (unless otherwise stated). Activity: in units of 10 ⁴ gmol ^-1 h ^-1 . M _w , M _w / _Mn : weight average molecular weight and polymer dispersibility index, respectively, measured by GPC in 1,2,4-trichlorobenzene at 150°C, relative to a polystyrene standard. The degree of branching = the number of branches per 1000 carbons, measured by hydrogen nuclear magnetic resonance spectroscopy, and the transmittance is the transmittance at a wavelength of 400 nm.

The polymerization time of Example 17 was 2h, and the polymerization time of Examples 18-19 was 3h.

Polymerization data in Table 3 Conclusion: With the decrease of ethylene pressure, the insertion rate of the polymer gradually increases, the molecular weight of the polymer also increases gradually, and the yield gradually decreases. As the comonomer concentration increases, the yield decreases and the comonomer insertion rate increases. The nuclear magnetic 1H-NMR spectrum of the copolymer of ethylene and cycloolefin monomer 13 in Example 19 is shown in FIG. 2 .

Examples 20-29 Effects of different catalysts on the copolymerization of ethylene and polar cycloolefin monomers catalyzed by late transition metal catalysts

The 75 mL glass pressure reactor connected to the gas line was first vacuum dried at 90 °C for at least 1 h. Then 23 mL of toluene and the specified amount of comonomer 13 or 2 were added to the reactor under an inert atmosphere, and then 10.0 μmol of the specified catalyst was dissolved in 2 mL of dichloromethane and injected into the polymerization system by syringe. Under rapid stirring (750 rpm), ethylene was passed in and kept at 8 bar. After 2 h, the pressure reactor was evacuated, 200 mL of hydrochloric acid ethanol was added to quench the polymerization reaction, and the polymer was filtered and dried in a vacuum oven to constant weight. The specific reaction conditions and results are shown in Table 4.

Table 4. Effects of different late transition metal catalysts on the copolymerization of ethylene polar monomers

Note: All data are based on at least two parallel experiments (unless otherwise stated). Activity: in units of 10 ⁴ gmol ^-1 h ^-1 . M _w , M _w / _Mn : weight average molecular weight and polymer dispersibility index, respectively, measured by GPC in 1,2,4-trichlorobenzene at 150°C, relative to a polystyrene standard. The degree of branching = the number of branches per 1000 carbons, as determined by proton NMR. The transmittance is the transmittance at a wavelength of 400 nm.

Comonomer 13 was used in Examples 20-25, and Comonomer 2 was used in Examples 26-29.

Table 4. Polymerization data Conclusion: With the increase of catalyst steric hindrance, the polymer insertion rate gradually decreased, but the polymer yield also increased gradually. Catalysts containing aromatic groups are more effective. The molecular weight and insertion rate of tert-butyl-mes-trimethoxy catalyst are the most balanced, and the highest molecular weight is 126,000. In addition, the nickel phosphine phenolate catalyst can also obtain a copolymer of ethylene and monomer 13 with a molecular weight of 108,000, which is better than the performance of other amide monomers reported in the literature. The visible see-through curve of the copolymer of ethylene and cycloolefin monomer 13 of Example 24 is shown in FIG. 4 .

Claims (10)

1. a cyclic olefin copolymer, is characterized in that, has the structure shown in formula (I):

Where m and n are the degree of polymerization, m:n≥1.5; R ₁ and R ₂ are independent hydrogen or saturated aliphatic hydrocarbon groups with 1-10 carbon atoms; R ₃ is alkyl, aryl, halogen, alkoxy, CF ₃ , NO ₂ , N(CH ₃ ) ₂ , benzyloxycarbonyl, tert-butoxycarbonyl, fluorenemethoxycarbonyl, allyloxycarbonyl, trimethylsilylethoxycarbonyl, phthaloyl, p-toluenesulfonyl, trifluoroacetyl, Trityl, 2,4-dimethoxybenzyl, p-methoxybenzyl or benzyl. 2 . The cyclic olefin copolymer according to claim 1 , wherein 20≧m:n≧2.3. 3 . 3. a kind of cyclic olefin copolymer according to claim 1 is characterized in that, described R ₁ and R ₂ are independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or hydrogen. 4. a kind of cyclic olefin copolymer according to claim 1, is characterized in that, described cyclic olefin copolymer specifically comprises following polymer:

5. the preparation method of a kind of cyclic olefin copolymer according to claim 1, is characterized in that, comprises the following steps: In an inert solvent, the cycloolefin monomer having the structure of formula (II) and α-olefin are polymerized in the presence of a catalyst to obtain a cycloolefin copolymer having the structure of formula (I);

In formula (I), m and n are the degree of polymerization, and m:n≥1.5; R ₁ and R ₂ are independent hydrogen or saturated aliphatic hydrocarbon groups with 1-10 carbon atoms; R ₃ is alkyl, aryl, halogen, alkoxy, CF ₃ , NO ₂ , N(CH ₃ ) ₂ , benzyloxycarbonyl, tert-butoxycarbonyl, fluorenemethoxycarbonyl, allyloxycarbonyl, trimethylsilylethoxycarbonyl, phthaloyl, p-toluenesulfonyl, trifluoroacetyl, Trityl, 2,4-dimethoxybenzyl, p-methoxybenzyl or benzyl. 6. the preparation method of a kind of cyclic olefin copolymer according to claim 5, is characterized in that, described α-olefin is ethylene, propylene, 1-butene, isobutene, 1-pentene, 2-methyl- 1-butene, 3-methyl-1-butene, 1-hexene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene or 2 -Ethyl-1-butene. 7 . The preparation method of a cyclic olefin copolymer according to claim 5 , wherein the catalyst is a phosphine sulfonic acid palladium phosphine phenol nickel catalyst. 8 . 8. the preparation method of a kind of cyclic olefin copolymer according to claim 7, is characterized in that, described catalyzer comprises the phosphine sulfonic acid palladium catalyst that di-o-methoxyphenyl replaces, 2-(2,6- Dimethoxybenzene) phenyl and phenyl substituted phosphine sulfonate palladium catalysts, dicyclohexyl substituted phosphine sulfonate palladium catalysts, bis-tert-butyl substituted phosphine sulfonate palladium catalysts, tert-butyl and mes-trimethoxybenzene phenyl-substituted phosphine sulfonate palladium catalyst, 2-(2,6-dimethoxybenzene) phenyl and phenyl-substituted phosphine phenoxide nickel catalyst. 9. The preparation method of a cycloolefin copolymer according to claim 5, wherein the molar ratio of the catalyst to the cycloolefin monomer having the structure of formula (II) is 1:200-2400; The molar ratio of the α-olefin to the cycloolefin monomer having the structure of formula (II) is (2.3-20):1. 10 . The method for preparing a cyclic olefin copolymer according to claim 5 , wherein the temperature of the polymerization reaction is 30° C. to 100° C., and the time of the polymerization reaction is 30 minutes to 240 minutes. 11 .

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