Polysiloxane functionalized polyolefin with multiple reaction sites as well as preparation method and application thereof

Abstract

The invention discloses polysiloxane functionalized polyolefin with multiple reaction sites, the structural general formula of the polysiloxane functionalized polyolefin is as follows: in the formula, Rz is selected from one or more of alpha-olefin, cycloolefin and non-conjugated diene containing 3-20 carbon atoms; rn is selected from one of CH3, # imgabs 0 # and # imgabs 1 #; x is selected from natural numbers of 1-100, y is selected from natural numbers of 500-2000, z is selected from natural numbers of 1-100, n is selected from natural numbers of 1-32, and m is selected from natural numbers of 32-200. When the polysiloxane functionalized polyolefin disclosed by the invention is used as a compatilizer for preparing the ethylene propylene diene monomer / silicone rubber blended rubber, the compatibility of the ethylene propylene diene monomer and the silicone rubber can be remarkably improved, and the mechanical strength and the heat resistance of the ethylene propylene diene monomer / silicone rubber blended rubber are remarkably enhanced. # imgabs2 #

Description

Technical Field

[0001] The invention relates to the technical field of rubber blending, and in particular to a polysiloxane functionalized polyolefin with multiple reaction sites, a preparation method thereof, and an application of the polysiloxane functionalized polyolefin in the preparation of EPDM rubber / silicone rubber blended rubber. Background Art

[0002] EPDM is a copolymer of ethylene, propylene and a third monomer. It has excellent electrical insulation and aging resistance and is widely used in wires and cables, automotive components and other fields. However, its heat resistance is limited. Silicone rubber is widely used in aerospace, electricity and other fields due to its excellent high and low temperature resistance and weather resistance, but its mechanical properties are weak and its cost is high.

[0003] Therefore, it is hoped that by blending EPDM and silicone rubber, the excellent mechanical properties of EPDM and the excellent heat resistance of silicone rubber can be integrated to produce a composite material with comprehensive performance. The challenge is that since the main chain of EPDM is composed of CC bonds, while silicone rubber is composed of Si-O bonds, the compatibility of the two is poor. At the same time, the difference in viscosity and vulcanization speed between the two rubbers also increases the difficulty of preparing excellent blending rubbers.

[0004] A Chinese patent document with application publication number CN109867789A discloses a compatibilizer, which is prepared from liquid EPDM rubber, hydrogenated silicone oil and a catalyst, and is used to improve the blending compatibility of EPDM rubber and silicone rubber, and to enhance the physical and mechanical properties and heat and aging resistance of the blended rubber. However, the structure of the compatibilizer is unclear, and the volume-increasing effect is not obvious. The tensile strength and elongation at break of the rubber are only increased by 8.4% and 11.5% at most, respectively, and the mechanical properties are limitedly improved, and the aging performance is not significantly improved either.

[0005] Kole (S. Kole, S. Roy, AKBhowmick, Influence of chemical interaction on the properties of Silicone-EPDM rubber blend, Polymer 36 (17) (1995) 3273-3277.) et al. studied the grafting of acrylamide into SR and the introduction of maleic anhydride / maleic acid into EPDM to enhance the compatibility between EPDM and SR through the interaction between the introduced carboxyl and amide groups. However, this method requires modification of the base material before the introduction of the reactive compatibilizer.

[0006] Ashokrao (C. AshokraoFuke, P. Anna Mahanwar, S., Modified ethylene-propylene-diene elastomer (EPDM) -contained silicone rubber / ethylene-propylene-diene elastomer (EPDM) blends: Effect of composition and electron beam crosslinking on mechanical, heat shrinkability, electrical, and morphological properties, J. Appl. Polym. Sci. 136 (29) (2019) 47787.) et al. reported that γ-radiation-induced methacrylic acid (MAA) grafted EPDM as a compatibilizer increased the degree of crosslinking, thereby significantly improving the mechanical properties of EPDM / silicone rubber blends during vulcanization. However, structural similarity causes the crosslinking sites to be mainly concentrated in the EPDM phase, which may impair compatibility to some extent.

[0007] It can be seen that the compatibilizers for EPDM rubber and silicone rubber disclosed in the prior art either have a general volume expansion effect or require a complex substrate control process, resulting in a high cost. Therefore, this research has important value and academic significance for the preparation of high-performance EPDM rubber / silicone rubber blends. Summary of the invention

[0008] In view of the above problems existing in the prior art, the present invention discloses a polysiloxane functionalized polyolefin with multiple reaction sites, which has a novel structure and possesses certain mechanical properties and can be used as a vulcanized rubber body; more importantly, the product can also be used as a compatibilizer to significantly improve the mechanical properties and heat resistance of EPDM rubber / silicone rubber blends.

[0009] The specific technical solutions are as follows:

[0010] A polysiloxane functionalized polyolefin having multiple reaction sites, the general structural formula of which is as follows:

[0011]

[0012] Where: R z Selected from α-olefins containing 3 to 20 carbon atoms 、 One or more of cyclic olefins and non-conjugated dienes;

[0013] R n Selected from CH3, One of;

[0014] x is selected from natural numbers ranging from 1 to 100, y is selected from natural numbers ranging from 500 to 2000, z is selected from natural numbers ranging from 1 to 100, n is selected from natural numbers ranging from 1 to 32, and m is selected from natural numbers ranging from 32 to 200.

[0015] The polysiloxane functionalized polyolefin disclosed in the present invention has a novel structure and is a terpolymer including ethylene, norbornene-based double-terminated polysiloxane and a third monomer. It has mechanical properties and can be used as a vulcanized rubber body. The weight average molecular weight of the polysiloxane functionalized polyolefin, the content of polysiloxane monomers in the copolymer, and the molecular weight of the polysiloxane macromonomer can all be adjusted over a wide range. In particular, the polysiloxane functionalized polyolefin has multiple reaction sites and can be used as a compatibilizer to prepare EPDM rubber / silicone rubber blends. By adjusting the above parameters, it tends to stabilize at the interface between EPDM rubber and silicone rubber during the blending process, significantly improving the mechanical properties of the EPDM rubber / silicone rubber blend, especially tensile strength and tear strength, as well as heat aging resistance.

[0016] Preferably, the molecular weight of the polysiloxane segment in the polysiloxane functionalized polyolefin is: 1.3 to 19.0 kg / mol;

[0017] Preferably, the mass content of the polysiloxane monomer in the polysiloxane functionalized polyolefin is 1 to 55%, and the mass content of the third monomer is 0.5 to 28%;

[0018] Preferably, the weight average molecular weight of the polysiloxane functionalized polyolefin is 80 to 300 kg / mol.

[0019] Preferably, in the polysiloxane functionalized polyolefin:

[0020] The α-olefin containing 3 to 20 carbon atoms is selected from

[0021] The cyclic olefin is selected from

[0022] The non-conjugated diene is selected from

[0023] The present invention also discloses a method for preparing the polysiloxane functionalized polyolefin having multiple reaction sites, comprising:

[0024] (1) using hydrogen-containing silane and siloxane ring as raw materials, preparing a double-terminal hydrogen-containing polysiloxane macromonomer through cationic ring-opening polymerization;

[0025] (2) using vinyl norbornene and the double-terminated hydrogen-containing polysiloxane macromonomer prepared in step (1) as raw materials, and obtaining a norbornene-based double-terminated polysiloxane macromonomer through a hydrosilylation reaction;

[0026] (3) Coordination copolymerization of the norbornene-based double-terminated polysiloxane macromonomer prepared in step (2) with ethylene and a third monomer to obtain the polysiloxane functionalized polyolefin having multiple reaction sites.

[0027] The preparation method disclosed by the invention comprises three-step reactions of cationic ring-opening polymerization, hydrosilylation and coordination copolymerization. By adjusting the molar ratio of the hydrogen-containing silane to the siloxane ring body in the cationic ring-opening polymerization reaction and the feeding molar concentration of the norbornene-based double-terminated polysiloxane macromonomer in the coordination copolymerization, the polysiloxane monomer content and the molecular weight of the polysiloxane macromonomer in the prepared polysiloxane functionalized polyolefin can be precisely regulated.

[0028] In step (1):

[0029] The siloxane ring body is selected from octamethylcyclotetrasiloxane or a side chain functionalized siloxane ring body having a structural formula as shown in the following formulas (II-1) to (II-3);

[0030]

[0031] Among them, octamethylcyclotetrasiloxane, 1,3,5-trimethyl-1,3,5-tri(3,3,3-trifluoropropyl)cyclotrisiloxane, and 2,2,4,6,6,8-hexamethyl-4,8-diphenylcyclotetrasiloxane can all be obtained through commercial channels; and the side chain functionalized siloxane rings shown in formulas (II-1) to (II-3) can be synthesized by themselves.

[0032] The side chain functionalized siloxane ring body is prepared by a hydrolysis reaction. The side chain functionalized siloxane ring body of formula (II-1) is prepared by hydrolyzing dimethyldichlorosilane and methylvinyldichlorosilane in azeotropic hydrochloric acid and adding a surfactant to prepare the side chain functionalized siloxane ring body;

[0033] Specifically include:

[0034] First, add constant boiling hydrochloric acid to a three-necked flask equipped with a condenser, then add a surfactant and stir until it is completely dissolved, then fully mix dimethyldichlorosilane and methylvinyldichlorosilane, and then add dropwise through a micro feed pump to react at 30-60°C; after the reaction, extract, separate and distill under reduced pressure on the crude product to obtain a side chain functionalized siloxane ring body of formula (II-1).

[0035] Preferred:

[0036] The molar ratio of dimethyldichlorosilane to methylvinyldichlorosilane is 1:0.33;

[0037] The surfactant is selected from sodium octane sulfonate.

[0038] To prepare the side chain functionalized siloxane rings shown in formula (II-2) to (II-3), the following preparation method is used:

[0039] First, add constant boiling hydrochloric acid to a three-necked flask equipped with a condenser, then add a surfactant and stir until it is completely dissolved, then fully mix dimethyldichlorosilane and methyldichlorosilane, and then add dropwise through a micro feed pump to react at 30-60°C; after the reaction, add ethylidene norbornene or 4-vinyl-1-cyclohexene to the intermediate product for a hydrosilylation reaction; when ethylidene norbornene is added, a side chain functionalized siloxane ring body of formula (II-2) is prepared; when 4-vinyl-1-cyclohexene is added, a side chain functionalized siloxane ring body of formula (II-3) is prepared.

[0040] Preferred:

[0041] The molar ratio of dimethyldichlorosilane to methylvinyldichlorosilane is 1:0.33;

[0042] The surfactant is selected from sodium octane sulfonate;

[0043] The temperature of the hydrosilylation reaction is 80°C;

[0044] The hydrosilylation reaction further requires the addition of a catalyst, which is specifically selected from common catalyst types in the art, such as Karstedt catalyst, chloroplatinic acid, and the like.

[0045] In step (1):

[0046] The hydrogen-containing silane is selected from 1,1,3,3-tetramethyldisiloxane;

[0047] The molar ratio of the hydrogen-containing silane to the siloxane ring is 1:(8-50);

[0048] Preferably, the molar ratio of the hydrogen-containing silane to the siloxane ring is 1:(16-50);

[0049] More preferably, the molar ratio of the hydrogen-containing silane to the siloxane ring is 1:(16-32);

[0050] Most preferably, the molar ratio of the hydrosilane to the siloxane ring is 1:32.

[0051] It has been found through experiments that the molecular weight of the polysiloxane macromonomer in the polysiloxane functionalized polyolefin can be precisely controlled by adjusting the above parameters. With the continuous optimization of the above parameters, the mechanical properties and aging resistance of the EPDM rubber / silicone rubber blend prepared using the polysiloxane functionalized polyolefin prepared by the present invention as a compatibilizer are continuously improved.

[0052] In step (1):

[0053] The cationic ring-opening polymerization is specifically:

[0054] The acid catalyst, the siloxane-containing ring body and the hydrogen-containing silane are uniformly mixed, and a cationic ring-opening polymerization is initiated at 0 to 85° C. to obtain a double-terminal hydrogen-containing polysiloxane;

[0055] The acid catalyst is selected from one or more of activated clay, trifluoroacetic acid and concentrated sulfuric acid.

[0056] Preferably, the acidic catalyst is selected from activated clay (H2Al2(SiO3)4-nH2O) or concentrated sulfuric acid, and activated clay is further preferred.

[0057] Preferably, the temperature of the cationic ring-opening polymerization is 50 to 80°C; more preferably 65 to 75°C.

[0058] Preferably, the crude product obtained by the cationic ring-opening polymerization is further filtered and distilled under reduced pressure.

[0059] In step (2):

[0060] The molar ratio of vinyl norbornene to the double-terminal hydrogen-containing polysiloxane macromonomer is (3-15):1;

[0061] Preferably, the molar ratio of vinyl norbornene to the dual-terminal hydrogen-containing polysiloxane macromonomer is 10:1.

[0062] The hydrosilylation reaction is carried out under the action of a catalyst at a reaction temperature of 50 to 100°C;

[0063] Preferably, the catalyst is selected from common catalyst types for hydrosilylation reactions, such as Karstedt catalyst or chloroplatinic acid.

[0064] Preferably, the temperature of the hydrosilylation reaction is 80-90°C, more preferably 85°C.

[0065] Preferably, the crude product obtained by the hydrosilylation reaction is further subjected to reduced pressure distillation.

[0066] In step (3), the coordination copolymerization specifically comprises:

[0067] Take a reaction device equipped with a sealed mechanical stirring device, replace the reaction system with an inert ethylene atmosphere without water and oxygen; then add a solvent, and add a co-catalyst, a norbornene-based double-terminated polysiloxane macromonomer, a third monomer and an activator in sequence, and then add a catalyst to initiate a polymerization reaction, and keep the ethylene pressure constant during the reaction. After the polymerization reaction is completed, the crude product is post-treated to obtain the polysiloxane functionalized polyolefin;

[0068] The molar ratio of the norbornene-dicapped polysiloxane macromonomer to the third monomer is 1:(1-100);

[0069] Preferably, the molar ratio of the norbornene-dicapped polysiloxane macromonomer to the third monomer is 1:(2-20);

[0070] More preferably, the molar ratio of the norbornene-dicapped polysiloxane macromonomer to the third monomer is 1:(2-4);

[0071] More preferably, the molar ratio of the norbornene-di-terminated polysiloxane macromonomer to the third monomer is 1:4.

[0072] The initial concentration of the norbornene-dicapped polysiloxane macromonomer in the reaction system is controlled to be (0.5-20) mmol / L;

[0073] Preferably, the initial concentration of the norbornene-dicapped polysiloxane macromonomer in the reaction system is controlled to be (1-10) mmol / L;

[0074] More preferably, the initial concentration of the norbornene-dicapped polysiloxane macromonomer in the reaction system is controlled to be (5-10) mmol / L;

[0075] More preferably, the initial concentration of the norbornene-di-terminated polysiloxane macromonomer in the reaction system is controlled to be 5 mmol / L.

[0076] Control the pressure in the reaction system to 0.1-1.0 MPa;

[0077] Preferably, the pressure in the reaction system is controlled to be 0.1-0.5 MPa;

[0078] More preferably, the pressure in the reaction system is controlled to be 0.1-0.3 MPa;

[0079] More preferably, the pressure in the reaction system is controlled to be 0.1 MPa.

[0080] The temperature of coordination copolymerization is 0-70°C;

[0081] Preferably, the coordination copolymerization temperature is 10 to 30° C. and the time is 5 to 30 min.

[0082] The coordination copolymerization reaction uses a common catalyst type in the art, such as a transition metal catalyst, specifically a Ziegler-Natta vanadium catalyst.

[0083] There is no special requirement for the types of the solvent, co-catalyst and activator, and they are all selected from common types in the art. For example, the solvent is selected from anhydrous toluene, anhydrous n-hexane, isoparaffin solvents (Ex Mobil, Isopar series), etc., the co-catalyst is selected from diethylaluminum chloride, and the activator is selected from ethyl trichloroacetate.

[0084] Preferably, the crude product obtained by the coordination copolymerization needs to be post-treated including washing and drying.

[0085] The invention also discloses an EPDM rubber / silicone rubber composite rubber, which uses the polysiloxane functionalized polyolefin with multiple reaction sites as a compatibilizer.

[0086] Preferably, the raw material composition of the EPDM rubber / silicone rubber blend comprises, by parts by mass:

[0087]

[0088] Preferably: in the polysiloxane functionalized polyolefin:

[0089] R z Selected from and / or or and At least one of combination of;

[0090] R n Selected from CH3,

[0091] The molecular weight of the polysiloxane chain segment is 6.1-18.6 kg / mol; the mass content of the polysiloxane monomer is 17-55%.

[0092] It has been found through experiments that when the polysiloxane functionalized polyolefin with the preferred structure is used as a compatibilizer, the prepared EPDM rubber / silicone rubber blend has higher mechanical properties and better aging resistance.

[0093] Preferably, the vulcanizing agent is selected from 2,5-dimethyl-2,5-bis-hexane and / or diisopropylbenzene peroxide;

[0094] Preferably, the vulcanization aid is selected from one or more of zinc oxide, stearic acid and silicone oil.

[0095] Preferably, a reinforcing agent such as nano-silicon dioxide and / or carbon black, which are common in the art, may be added to the raw materials.

[0096] Further preferably, the raw material composition of the EPDM rubber / silicone rubber blend comprises, by parts by mass:

[0097]

[0098] More preferably, the mass fraction of the compatibilizer is 2 to 4 parts.

[0099] Compared with the prior art, the present invention has the following beneficial effects:

[0100] The invention discloses a novel polysiloxane functionalized polyolefin, which is a multi-component copolymer comprising ethylene, norbornene-based double-terminated polysiloxane and a third monomer, and has mechanical properties and can be used as a vulcanized rubber body.

[0101] The invention also discloses a preparation method of the polysiloxane functionalized polyolefin. By accurately controlling the process parameters, the weight average molecular weight of the copolymer, the content of the polysiloxane monomer in the copolymer, and the molecular weight of the polysiloxane macromonomer can be adjusted in a wide range.

[0102] The polysiloxane functionalized polyolefin disclosed in the present invention has multiple reaction sites and can also be used as a compatibilizer to prepare EPDM rubber / silicone rubber blends. By adjusting parameters, the polysilicone functionalized polyolefin tends to be stabilized at the interface between EPDM rubber and silicone rubber during the blending process, thereby significantly improving the mechanical properties of the EPDM rubber / silicone rubber blend, especially the tensile strength and tear strength, as well as the heat aging resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0103] Figure 1 The hydrogen nuclear magnetic resonance spectrum of the double-terminated hydrogen-containing polysiloxane and the norbornene-terminated polysiloxane macromonomer prepared in Example 1;

[0104] Figure 2 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 1 prepared in Example 1;

[0105] Figure 3 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 7 prepared in Example 7;

[0106] Figure 4 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 8 prepared in Example 8;

[0107] Figure 5 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 9 prepared in Example 9;

[0108] Figure 6 The hydrogen nuclear magnetic resonance spectra of the siloxane rings prepared in Examples 12, 13 and 14 respectively;

[0109] Figure 7 H NMR spectra of the norbornene-based double-terminated side chain functionalized polysiloxane macromonomers prepared in Examples 12, 13, and 14, respectively, and the norbornene-based single-terminated polysiloxane macromonomer prepared in Comparative Example 3;

[0110] Figure 8 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 12 prepared in Example 12;

[0111] Fig. 9 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 13 prepared in Example 13;

[0112] Fig.10 TEM images of EPDM rubber / silicone rubber blends prepared in Example 13 and Comparative Example 2, respectively;

[0113] Fig.11 This is the high temperature hydrogen nuclear magnetic resonance spectrum of the product prepared in Comparative Example 3. DETAILED DESCRIPTION

[0114] In order to further illustrate the purpose, technical solutions and advantages of the present invention, the present invention is further described in detail below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereby.

[0115] The EPDM rubber and silicone rubber are both commercially available, EPDM rubber (Dow Group, 4725P); vinyl silicone rubber (Hosun Silicon Industry, vinyl content 0.22 mol%).

[0116] Example 1

[0117] (1) 0.75 g of activated clay, 23.7 g of octamethylcyclotetrasiloxane (0.08 mol) and 1.34 g of 1,1,3,3-tetramethyldisiloxane (0.01 mol) were added to a 100 mL flask under a nitrogen atmosphere; after reacting at 65° C. for 14 h, the catalyst was filtered out, and then the unreacted raw materials were removed by reduced pressure distillation (95° C., 5 kPa) to obtain a colorless and transparent double-terminal hydrogen-containing polysiloxane;

[0118] (2) Add 1.2 g of vinyl norbornene (0.1 mol) and Karstedt catalyst (Pt: 1.2 μmol) to a round-bottom flask under a nitrogen atmosphere, and then dropwise add 23 g (0.01 mol) of the double-terminated hydrogen-containing polysiloxane prepared in step (1); react at 85° C. for 24 h, and then remove unreacted vinyl norbornene by reduced pressure distillation (95° C., 5 kPa) to obtain a colorless and transparent norbornene-based double-terminated polysiloxane macromonomer. The number average molecular weight of the norbornene-based double-terminated polysiloxane macromonomer was determined by GPC analysis to be 3.2 kg / mol;

[0119] (3) A 250 mL glass reactor was evacuated for 10 min, and then ethylene was introduced to maintain the system pressure at 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, and anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), 5-ethylidene-2-norbornene (1.125 mmol, initial concentration of 20 mmol / L) and norbornene-based double-terminated polysiloxane macromonomer prepared in step (2) (0.94 g, 0.375 mmol, initial concentration of 5 mmol / L) were added respectively, and after stirring for 5 min, 1 μmol VCl3(THF)3 was injected to initiate the reaction. During the process, ethylene gas was continuously introduced to maintain the system pressure at 0.1 MPa. After a period of reaction, the mixture was poured into acidic ethanol for precipitation. The filter cake was washed three times with a mixed solution of anhydrous ethanol and tetrahydrofuran in a ratio of 3:1 and vacuum dried at 60°C for 12 h to obtain 1.1 g of a white solid product, which was a polysiloxane functionalized polyolefin with multiple reaction sites and was recorded as compatibilizer 1.

[0120] (4) adding 70 parts by weight of EPDM rubber, 30 parts by weight of silicone rubber and 2 parts by weight of the compatibilizer synthesized in step (3) into an internal mixer and mixing at 100° C. for 5 min;

[0121] (5) adding 30 parts by mass of nano-silicon dioxide and 3 parts by mass of zinc oxide to an internal mixer and mixing for 10 minutes, then adding 1.2 parts by mass of 2,5-dimethyl-2,5-bishexane, mixing for 5 minutes and then discharging;

[0122] (6) After 24 h of storage, the rubber mixture was hot pressed and vulcanized at 180 °C, and then subjected to mechanical testing and thermal oxidative aging testing.

[0123] Figure 1 ] are the hydrogen nuclear magnetic resonance spectra of the double-terminated hydrogen-containing polysiloxane prepared in step (1) of this embodiment and the norbornene-based double-terminated polysiloxane macromonomer prepared in step (2).

[0124] Figure 2 This is a high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer 1 prepared in this example. According to the figure, the compatibilizer 1 is a terpolymer of ethylene / norbornene-based double-terminated polysiloxane / 5-ethylidene-2-norbornene, and the structural formula is shown below:

[0125]

[0126] The test showed that the polymerization activity of the compatibilizer 1 prepared in this example was as high as 7.4×10 6g / (mol·h). The number average molecular weight of the polysiloxane side chain in the copolymer is 3.2kg / mol, the content of polysiloxane is 14.1wt%, and the content of the third monomer 5-ethylidene-2-norbornene is 3.3wt%. The weight average molecular weight of the compatibilizer is 93kg / mol as determined by GPC analysis. The crystallization temperature and melting temperature of the compatibilizer are further characterized by a differential scanning calorimeter (Q2500, TA), and the test results are shown in Table 1.

[0127] Example 2

[0128] The preparation process is basically the same as that in Example 1, except that:

[0129] In step (1), the amount of octamethylcyclotetrasiloxane added was replaced with 37.9 g (0.128 mol), and the amount of 1,1,3,3-tetramethyldisiloxane added was replaced with 1.07 g (0.008 mol);

[0130] In step (2), the amount of vinyl norbornene added was replaced with 7.4 g (0.062 mol), and the amount of double-terminal hydrogen-containing polysiloxane added was replaced with 32.2 g (0.0062 mol);

[0131] In step (3), the amount of norbornene-dicapped polysiloxane added was replaced with 1.95 g (0.375 mmol, initial concentration was 5 mmol / L).

[0132] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 2, and its performance parameters are listed in the following Table 1.

[0133] Example 3

[0134] The preparation process is basically the same as that in Example 1, except that:

[0135] In step (1), the amount of octamethylcyclotetrasiloxane added was replaced with 37.9 g (0.128 mol), and the amount of 1,1,3,3-tetramethyldisiloxane added was replaced with 0.54 g (0.004 mol);

[0136] In step (2), the amount of vinyl norbornene added was replaced with 4.8 g (0.04 mol), and the amount of double-terminal hydrogen-containing polysiloxane added was replaced with 42.8 g (0.004 mol);

[0137] In step (3), the amount of norbornene-dicapped polysiloxane added was replaced with 4.0 g (0.375 mmol, initial concentration was 5 mmol / L).

[0138] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 3, and its performance parameters are listed in the following Table 1.

[0139] Example 4

[0140] The preparation process is basically the same as that in Example 1, except that:

[0141] In step (1), the amount of octamethylcyclotetrasiloxane added was replaced with 37.9 g (0.128 mol), and the amount of 1,1,3,3-tetramethyldisiloxane added was replaced with 0.34 g (0.0026 mol);

[0142] In step (2), the amount of vinyl norbornene added was replaced with 2.4 g (0.02 mol), and the amount of double-terminal hydrogen-containing polysiloxane added was replaced with 29.2 g (0.002 mol);

[0143] In step (3), the amount of norbornene-dicapped polysiloxane added was replaced with 5.6 g (0.375 mmol, initial concentration was 5 mmol / L).

[0144] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 4, and its performance parameters are listed in the following Table 1.

[0145] Example 5

[0146] The preparation process is basically the same as that in Example 3, except that the amount of norbornene-based di-terminated polysiloxane added in step (3) is replaced with 0.8 g (0.075 mmol, initial concentration is 1 mmol / L).

[0147] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 5, and its performance parameters are listed in the following Table 1.

[0148] Example 6

[0149] The preparation process is basically the same as that in Example 3, except that the amount of norbornene-based di-terminated polysiloxane added in step (3) is replaced with 8.1 g (0.756 mmol, initial concentration is 10 mmol / L).

[0150] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 6, and its performance parameters are listed in the following Table 1.

[0151] Example 7

[0152] The preparation process is substantially the same as that in Example 3, except that the third monomer 5-ethylidene-2-norbornene in step (3) is replaced by an equimolar amount of cyclopentadiene.

[0153] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 7, and its performance parameters are listed in the following Table 1.

[0154] Figure 3 The high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer prepared in this example shows that the compatibilizer 7 is a terpolymer of ethylene / norbornene-based double-terminated polysiloxane / cyclopentadiene, and the structural formula is shown below:

[0155]

[0156] Example 8

[0157] The preparation process is substantially the same as that in Example 3, except that the third monomer 5-ethylidene-2-norbornene in step (3) is replaced by an equimolar amount of norbornene.

[0158] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 8, and its performance parameters are listed in the following Table 1.

[0159] Figure 4 The high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer prepared in this example shows that the compatibilizer 8 is a terpolymer of ethylene / norbornene-based double-terminated polysiloxane / norbornene, and the structural formula is shown below:

[0160]

[0161] Example 9

[0162] Steps (1) to (2) are the same as those in Example 3.

[0163] (3) A 250 mL glass reactor was evacuated for 10 min, and then ethylene was charged to maintain the system pressure at 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, and anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), 5-ethylidene-2-norbornene (1.125 mmol, initial concentration of 20 mmol / L) and norbornene-based double-terminated polysiloxane macromonomer (4.0 g, 0.375 mmol, initial concentration of 5 mmol / L) prepared in step (2) were added respectively. After stirring for 5 min, 1 μmol VCl3(THF)3 was injected to initiate the reaction. During the process, ethylene / propylene mixed gas was continuously charged to maintain the system pressure at 0.1 MPa, wherein the molar ratio of ethylene to propylene was 1:3. After reacting for a period of time, the mixture was poured into acidic ethanol for precipitation. The filter cake was washed three times with a mixed solution of anhydrous ethanol and tetrahydrofuran in a ratio of 3:1 and dried in vacuum at 60°C for 12 h to obtain 1.2 g of a white solid product, which was recorded as compatibilizer 9.

[0164] Steps (4) to (6) are the same as in Example 3.

[0165] The performance parameters of the compatibilizer 9 prepared in this example are listed in Table 1 below.

[0166] Figure 5 This is a high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer prepared in this example. It can be observed that compatibilizer 9 is a tetrapolymer of ethylene / propylene / 5-ethylidene-2-norbornene / norbornene-based double-terminated polysiloxane, and the structural formula is shown below:

[0167]

[0168] Example 10

[0169] The preparation process is basically the same as that of Example 3, except that the reaction solvent added in step (3) is replaced by anhydrous n-hexane.

[0170] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 10, and its performance parameters are listed in the following Table 1.

[0171] Embodiment 11

[0172] The preparation process is basically the same as that of Example 3, except that in step (3), ethylene is charged to maintain the pressure of the reaction system at 0.5 MPa.

[0173] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 11, and its performance parameters are listed in the following Table 1.

[0174] Example 12

[0175] (1) In a nitrogen atmosphere, 150 mL of azeotropic hydrochloric acid and 0.8 g (3.7 mmol) of sodium octane sulfonate were added to a 250 mL three-necked flask equipped with a condenser, and the mixture was stirred until completely dissolved. 38.6 g (0.3 mol) of dimethyldichlorosilane and 14.1 g (0.1 mol) of methylvinyldichlorosilane were mixed evenly and then added dropwise to the three-necked flask at 30° C. (100 mL / min). After the addition was completed, stirring was continued for 10 min. After extraction and separation, anhydrous calcium chloride was added and stirred for 12 h. After filtration, the fraction at 100-130° C. was collected by reduced pressure distillation at 5 kPa to obtain a colorless and transparent siloxane mixed ring containing vinyl groups in the side chains.

[0176] The H NMR spectrum of the mixed siloxane ring containing vinyl groups in the side chains prepared in this example is as follows: Figure 6 As shown in the figure, the structural formula of the siloxane ring prepared in this embodiment is as follows:

[0177]

[0178] (2) under nitrogen atmosphere, 0.75 g of activated clay, 23.7 g of the side chain vinyl siloxane mixed ring body (0.08 mol) obtained in step (1) and 0.34 g of 1,1,3,3-tetramethyldisiloxane (2.5 mmol) were added to a 100 mL flask; after reacting at 75° C. for 14 h, the catalyst was filtered out, and the unreacted raw materials were removed by reduced pressure distillation (95° C., 5 kPa) to obtain a colorless and transparent terminal hydrogen-containing polysiloxane containing a vinyl group in the side chain. The number average molecular weight of the terminal hydrogen-containing polysiloxane containing a vinyl group in the side chain was 11.2 kg / mol as determined by GPC analysis;

[0179] (3) Add 1.2 g of vinyl norbornene (0.01 mol) and Karstedt catalyst (Pt: 1.2 μmol) to a round-bottom flask under a nitrogen atmosphere, and then add dropwise 11.2 g (1 mmol) of the hydrogen-terminated polysiloxane prepared in step (2); react at 85° C. for 24 h, remove unreacted vinyl norbornene by reduced pressure distillation (95° C., 5 kPa) to obtain a colorless and transparent norbornene-based double-terminated polysiloxane macromonomer containing vinyl groups in the side chain. The number average molecular weight of the norbornene-based double-terminated polysiloxane macromonomer containing vinyl groups in the side chain is 11.4 kg / mol as determined by GPC analysis;

[0180] The hydrogen nuclear magnetic resonance spectrum of the norbornene-based double-terminated side chain functionalized polysiloxane macromonomer prepared in this example is as follows: Figure 7 As shown in the figure, the structural formula of the side chain functionalized polysiloxane macromonomer prepared in this embodiment is as follows:

[0181]

[0182] (4) A 250 mL glass reactor was evacuated for 10 min, and then ethylene was introduced to maintain the system pressure at 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, and anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), 5-ethylidene-2-norbornene (1.125 mmol, initial concentration of 20 mmol / L) and norbornene-based double-terminated polysiloxane macromonomer prepared in step (3) (4.3 g, 0.375 mmol, initial concentration of 5 mmol / L) were added respectively, and after stirring for 5 min, 1 μmol VCl3(THF)3 was injected to initiate the reaction. During the process, ethylene gas was continuously introduced to maintain the system pressure at 0.1 MPa. After reacting for a period of time, it was poured into acidic ethanol for precipitation. The filter cake was washed three times with a mixed solution of anhydrous ethanol and tetrahydrofuran = 3:1, and vacuum dried at 60°C for 12 hours to obtain 0.39 g of a white solid product, which was recorded as compatibilizer 12. The performance parameters are listed in Table 1 below.

[0183] Steps (5) to (7) are exactly the same as those in Example 3.

[0184] Figure 8 The high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer prepared in this example shows that the compatibilizer 12 is a terpolymer of ethylene / norbornene-based double-terminated polysiloxane macromonomer containing vinyl groups in the side chain / 5-ethylidene-2-norbornene, and the theoretical structural formula is shown below:

[0185]

[0186] Embodiment 13

[0187] (1) In a nitrogen atmosphere, 150 mL of azeotropic hydrochloric acid and 0.8 g (3.7 mmol) of sodium octane sulfonate were added to a 250 mL three-necked flask equipped with a condenser, and the mixture was stirred until completely dissolved. 38.6 g (0.3 mol) of dimethyldichlorosilane and 11.5 g (0.1 mol) of methyldichlorosilane were mixed evenly and then added dropwise to the three-necked flask at 30° C. (100 mL / min). After the addition was completed, stirring was continued for 10 min. After extraction and separation, anhydrous calcium chloride was added and stirred for 12 h. After filtering, the fraction of 100 to 115° C. was collected by reduced pressure distillation at 5 kPa to obtain A colorless and transparent siloxane mixed ring body containing hydrogen groups in the side chain; it is also necessary to introduce ethylidene norbornene in the side group through hydrosilylation, replace the atmosphere in a 100mL flask with a nitrogen atmosphere, add 27.5g of ethylidene norbornene and Karstedt catalyst (Pt: 1.2μmol), and add 12.5g of the above-prepared siloxane mixed ring body containing hydrogen groups in the side chain at 80°C, the addition rate is 0.5mL / min, and the reaction is continued for 24h after the addition is completed, and then the unreacted raw materials are removed by reduced pressure distillation (85°C, 5kPa) to obtain a colorless and transparent siloxane mixed ring body containing ethylidene norbornene groups in the side chain.

[0188] The H NMR spectrum of the mixed siloxane ring containing ethylidene norbornene groups in the side chains prepared in this example is as follows: Figure 6 As shown in the figure, the structural formula of the siloxane ring prepared in this embodiment is as follows:

[0189]

[0190] Steps (2) to (7) are the same as in Example 3.

[0191] The hydrogen nuclear magnetic resonance spectrum of the norbornene-based double-terminated polysiloxane macromonomer containing ethylidene norbornene groups in the side chain prepared in this example is as follows: Figure 7 As shown in the figure, the structural formula is as follows:

[0192]

[0193] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 13, and its performance parameters are listed in the following Table 1.

[0194] Fig. 9 The high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer prepared in this example shows that the compatibilizer 13 is a terpolymer of ethylene / norbornene-based double-terminated polysiloxane macromonomer containing ethylidene norbornene groups on the side chain / 5-ethylidene-2-norbornene, and the structural formula is shown below:

[0195]

[0196] Fig.10 TEM image of EPDM / silicone rubber blend prepared in this embodiment. In the figure, TEM image of EPDM / silicone rubber blend prepared in Comparative Example 2 is also given for comparison. In the TEM image, the gray irregular area corresponds to the silicone rubber phase, the brighter area corresponds to the EPDM phase, and the dark spots are ZnO particles. A larger phase size is observed in Comparative Example 2, which means that EPDM and silicone rubber are incompatible. After adding compatibilizer 13, it is observed that the phase size of both EPDM and silicone rubber regions is reduced, indicating that compatibility is improved.

[0197] Embodiment 14

[0198] The preparation process is basically the same as that of Example 13, except that the monomer added in the post-treatment hydrosilylation in step (1) is replaced by an equimolar amount of 4-vinyl-1-cyclohexene instead of ethylidene norbornene.

[0199] The H NMR spectrum of the siloxane mixed ring containing 4-vinyl-1-cyclohexene in the side chain prepared in this example is as follows: Figure 6 As shown in the figure, the structural formula is as follows:

[0200]

[0201] The hydrogen nuclear magnetic resonance spectrum of the norbornene-based double-terminated side chain functionalized polysiloxane macromonomer prepared in this example is as follows: Figure 7 As shown in the figure, the structural formula is as follows:

[0202]

[0203] The polysiloxane functionalized polyolefin prepared in this example is recorded as compatibilizer 14, and its performance parameters are listed in the following Table 1.

[0204] Compatibilizer 14 prepared in this example: terpolymer of ethylene / norbornene-based double-terminated polysiloxane macromonomer containing cyclohexenyl groups on the side chain / 5-ethylidene-2-norbornene, the theoretical structural formula of which is shown below:

[0205]

[0206] The copolymer was cross-linked and the molecular weight and polysiloxane insertion could not be measured.

[0207] Embodiment 15

[0208] The preparation process is basically the same as that of Example 13, except that the amount of compatibilizer added in step (4) is replaced with 1 part by mass.

[0209] Example 16

[0210] The preparation process is basically the same as that of Example 13, except that the amount of compatibilizer added in step (4) is replaced with 4 parts by mass.

[0211] Embodiment 17

[0212] The preparation process is basically the same as that of Example 13, except that the amount of compatibilizer added in step (4) is replaced with 6 parts by mass.

[0213] Comparative Example 1

[0214] (1) Evacuate a 250 mL glass reactor for 10 min, then charge ethylene to maintain the system pressure at 0.1 MPa. Repeat the operation for 6 cycles, set the temperature at 30°C, add anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), and 5-ethylidene-2-norbornene (1.125 mmol, initial concentration is 20 mmol / L), stir for 5 min, and inject 1 μmol VCl3(THF)3 to initiate the reaction. During the process, charge ethylene gas continuously to maintain the system pressure at 0.1 MPa. After a period of reaction, pour into acidic ethanol for precipitation. Wash the filter cake three times with anhydrous ethanol and vacuum dry at 60°C for 12 h to obtain 0.95 g of white solid comparative polymer.

[0215] (2) 70 parts by weight of EPDM rubber, 30 parts by weight of silicone rubber and 2 parts by weight of the compatibilizer synthesized in step (1) were added into an internal mixer and mixed at 100° C. for 5 minutes.

[0216] (3) 30 parts by mass of nano-silicon dioxide and 3 parts by mass of zinc oxide were added to the internal mixer and kneaded for 10 minutes, followed by 1.2 parts by mass of 2,5-dimethyl-2,5-bishexane. The mixture was kneaded for 5 minutes before discharging.

[0217] (4) After 24 h of storage, the rubber mixture was hot pressed and vulcanized at 180 °C, and then subjected to mechanical testing and thermal oxidative aging testing.

[0218] The polymer prepared in this comparative example is: a binary copolymer of ethylene / 5-ethylidene-2-norbornene, and its various performance parameters are listed in the following Table 1, and its structural formula is shown as follows:

[0219]

[0220] Comparative Example 2

[0221] (1) 70 parts by weight of EPDM rubber and 30 parts by weight of silicone rubber were added to an internal mixer and kneaded at 100° C. for 5 minutes.

[0222] (2) 30 parts by mass of nano-silicon dioxide and 3 parts by mass of zinc oxide were added to the internal mixer and kneaded for 10 minutes, followed by 1.2 parts by mass of 2,5-dimethyl-2,5-bishexane. The mixture was kneaded for 5 minutes before discharging.

[0223] (3) After 24 h of storage, the rubber mixture was hot pressed and vulcanized at 180 °C, and then subjected to mechanical testing and thermal oxidative aging testing.

[0224] Comparative Example 3

[0225] (1) Under nitrogen atmosphere, 9.0 g of 5-vinyl-2-norbornene (0.075 mol) and Karstedt catalyst (Pt: 0.9 μmol) were added to a 100 mL flask, and 2.84 g (0.03 mol) of dimethyl monochlorosilane was added dropwise; after reacting for 24 h, unreacted 5-vinyl-2-norbornene was removed by rotary evaporation (95 ° C, 5 kPa) to obtain light yellow ethyl norbornene-based dimethylchlorosilane.

[0226] (2) In a nitrogen atmosphere at 10°C, 44.4 g (0.2 mol) of hexamethylcyclotrisiloxane was added to a round-bottom flask, and then 25 mL of tetrahydrofuran and 2 mL of n-butyl lithium / hexane solution (2.4 M) were added to initiate anionic ring-opening polymerization. After reacting for 2 h, 1.06 g (5 mmol) of ethyl norbornene dimethyl chlorosilane was added for end-capping to obtain norbornene-based mono-terminated polysiloxane. GPC analysis showed that the number average molecular weight of the norbornene-based mono-terminated polysiloxane macromonomer was 11.0 kg / mol.

[0227] (3) A 250 mL glass reactor was evacuated for 10 min, and then ethylene was charged to maintain the system pressure at 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, and anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), norbornene-terminated polysiloxane macromonomer (4.1 g, 0.375 mmol, initial concentration of 5 mmol / L) and 5-ethylidene-2-norbornene (1.125 mmol, initial concentration of 20 mmol / L) were added respectively. After stirring for 5 min, 1 μmol VCl3(THF)3 was injected to initiate the reaction. During the process, ethylene gas was continuously charged to maintain the system pressure at 0.1 MPa. After a period of reaction, the mixture was poured into acidic ethanol for precipitation. The filter cake was washed three times with anhydrous ethanol and vacuum dried at 60°C for 12 h to obtain 1.10 g of white solid polymer.

[0228] Steps (4) to (6) are the same as in Example 3.

[0229] The performance parameters of the polymer prepared in this comparative example are listed in the following Table 1.

[0230] Fig.11 This is a high temperature hydrogen nuclear magnetic resonance spectrum of the polymer prepared in this comparative example. According to the figure, it can be seen that it is a terpolymer of ethylene / norbornene-based single-terminated polysiloxane / 5-ethylidene-2-norbornene, and the structural formula is shown below:

[0231]

[0232] The performance parameters of the polysiloxane functionalized polyolefins prepared in each example and the polymers prepared in the comparative example are listed in the following Table 1.

[0233] Table 1

[0234]

[0235] The mechanical properties of the polysiloxane functionalized polyolefins prepared in each example are listed in Table 2 below.

[0236] Table 2

[0237]

[0238]

[0239] By comparing the data in Tables 1 and 2, the following conclusions can be drawn: the norbornene-based double-terminated polysiloxane macromonomers participating in the copolymerization all show excellent polymerization activity; the insertion of the norbornene-based double-terminated polysiloxane macromonomer destroys the crystallization ability of the copolymer, and to a certain extent reduces the mechanical properties of the copolymer; since the norbornene-based double-terminated polysiloxane macromonomer has better solubility in toluene system than in n-hexane solvent, the polymerization activity and molecular weight will be higher; under high pressure conditions, the concentration of gas molecules (such as olefin monomers such as ethylene) will increase significantly. According to the gas state equation, when the volume V and temperature T remain unchanged, more monomer molecules mean that the collision frequency between monomer molecules and between monomer molecules and the active center of the catalyst is greatly increased per unit time and per unit volume, so the molecular weight and activity of the polymerization product will be higher, but since the polysiloxane macromonomer is a liquid, increasing the pressure will have a negative impact on the polymerization product. The concentration of the polysiloxane macromonomer has little effect, so the insertion rate of the polysiloxane macromonomer will be slightly lower; the polymerization activity of the polysiloxane macromonomer with a functionalized double bond on the side chain is lower than that of the polysiloxane macromonomer with a silyl methyl side chain. The side chain of the compatibilizer 12 prepared in Example 12 contains a vinyl group, which is more likely to react secondary and contact with the active center, but because the vinyl group on the side chain is closer to the polysiloxane segment, the active center is poisoned, which greatly reduces the polymerization activity; the compatibilizer 13 prepared in Example 13 has a relatively high polymerization activity because the side chain is an ethylidene group with low reaction activity, but the activity is still reduced; the compatibilizer 14 prepared in Example 14 has a cyclohexenyl side chain, which is similar to the activity of the double bond in the ring terminated by the norbornene group, and cross-linking occurs during the copolymerization process, resulting in the inability to measure the molecular weight and the polysiloxane insertion rate.

[0240] The EPDM rubber / silicone rubber blends prepared in each embodiment and comparative example were subjected to tensile tests using a Zwick / Roell Z020 universal material testing machine at a tensile rate of 50 mm / min. The results are summarized in Table 3:

[0241] Table 3

[0242]

[0243]

[0244] In Table 3 above, Comparative Example 1 is an EPDM rubber / silicone rubber blended rubber modified by a copolymer without polysiloxane monomer insertion as a compatibilizer, and its mechanical strength is poor, with tensile strength, elongation at break and tear strength being only 8.9 MPa, 526% and 19.5 kN / m respectively; Comparative Example 2 is a blended rubber prepared by directly blending EPDM rubber and silicone rubber without adding any compatibilizer, and its mechanical strength is also poor, with tensile strength, elongation at break and tear strength being only 9.5 MPa, 437% and 18.3 kN / m respectively. The compatibilizer synthesized by the present invention is added to Examples 1 to 17, and its tensile strength, elongation at break and tear strength are greatly improved.

[0245] By comparing Examples 1 to 4, it can be found that when the degree of polymerization of the polysiloxane macromonomer is about 32 (molecular weight is about 11 kg / mol, Example 3), the obtained compatibilizer has the best compatibility improvement, and the final EPDM rubber / silicone rubber blend has the best mechanical properties. The reason may be that when the polysiloxane side chain is shorter, the gel content of the polymerization product is higher and it is difficult to disperse, while the molecular weight of the macromonomer with a degree of polymerization of about 50 significantly exceeds the entanglement threshold molecular weight of polysiloxane, which increases the entanglement of the polysiloxane chain segments and affects the compatibility.

[0246] By comparing Examples 3, 5 and 6, it can be found that when the initial feed concentration of the polysiloxane macromonomer is 5 mmol / L, the EPDM rubber / silicone rubber blend obtained by blending with the prepared compatibilizer has the best mechanical properties.

[0247] By comparing Examples 3, 7 and 8, it can be found that when the third monomer is ethylidene norbornene, the obtained compatibilizer has the best performance. This may be because when the third monomer is added in an equimolar amount, the insertion rate of cyclopentadiene is relatively low, and it cannot effectively participate in the vulcanization process, resulting in a low crosslinking density of the modified blended rubber after vulcanization. At the same time, since the norbornene structure has no extra reaction sites, the improvement in mechanical strength is also limited.

[0248] By comparing Examples 3 and 9, it can be found that after adding propylene as a polymerization monomer, the compatibility effect is good. The tensile strength, elongation at break and tearing strength of the combined rubber of Example 9 can also reach 16.6 MPa, 591% and 27.5 kN / m. However, considering that the preparation cost is higher, compatibilizer 3 is more preferred.

[0249] Comparing Examples 3 and 10, since the n-hexane system has poor solubility for polysiloxane, the insertion rate is affected and the performance of the obtained compatibilizer is slightly reduced.

[0250] By comparing Examples 3 and 11, it can be found that under higher polymerization pressure, the coordination polymerization activity is extremely high. This is because after the ethylene pressure is increased from 0.1 MPa to 0.5 MPa, the solubility of ethylene in the solvent (toluene in the example) increases, while maintaining the same initial concentration of the polysiloxane macromonomer, so the polysiloxane macromonomer is relatively more difficult to diffuse to the catalytic center. Therefore, the polysiloxane insertion rate of Example 11 is less than that of Example 3, so compatibilizer 3 is more preferred.

[0251] Comparing Examples 3, 12, 13 and 14, the influence of the type of reaction sites of the polysiloxane side chain on the compatibilization effect of the compatibilizer is explored. Compatibilizer 13 is the most preferred compatibilizer. This is because when the polysiloxane macromonomer contains vinyl in the side chain, the vinyl is more likely to react secondary and contact with the active center. However, since the vinyl on the side chain is closer to the polysiloxane segment, the active center is poisoned, which greatly reduces the polymerization activity and the insertion rate of the polysiloxane. When the polysiloxane macromonomer contains cyclohexenyl in the side chain, cross-linking occurs during the copolymerization process. The compatibilizer is difficult to disperse evenly during blending, so the compatibility is affected. Therefore, among all the synthesized compatibilizers, compatibilizer 13 is the most preferred compatibilizer, which can retain three reaction sites.

[0252] By comparing Examples 13, 15, 16 and 17, it can be seen that the mass fraction of the added compatibilizer is also very important. When the added mass fraction is too small, the compatibilization effect is limited. However, when the amount of the compatibilizer added exceeds a certain amount, the compatibilizer itself tends to form micelles, which in turn creates defects in the blend.

[0253] It can also be observed from the TEM images of the EPDM rubber / silicone rubber blend slices prepared in Example 13 and Comparative Example 2 respectively that in Example 3 after adding compatibilizer 3, the phase separation size between EPDM rubber and silicone rubber is significantly reduced, indicating that the compatibility of EPDM rubber and silicone rubber is increased.

[0254] In order to further evaluate the aging performance of the EPDM rubber / silicone rubber blend, the vulcanized rubber samples prepared in Examples 3, 13, 15 to 17 and Comparative Examples 1, 2, and 3 were placed in a hot oxygen aging box for aging at an aging temperature of 125°C for 48 h and 72 h, respectively. The mechanical properties of the aged samples were tested as described above, and the results are summarized in Table 4.

[0255] Table 4

[0256]

[0257] The data in Comparative Table 3 show that the tensile strength and elongation at break of the blended rubber after aging by only adding the compatibilizer synthesized by the present invention without adding any anti-aging additive are better than those of Comparative Examples 1 and 2. The compatibility between the two components of the EPDM rubber / silicone rubber blend without adding a compatibilizer is poor, and the silicone rubber is dispersed in EPDM with a large domain size and uneven distribution, and its protective effect cannot be effectively exerted. By improving the compatibility, the weather resistance of the silicone rubber can be better utilized.

[0258] The above examples are intended to help understand the method and key points of the present invention. The contents of this specification should not be construed as limiting the present invention.

Claims

1. A polysiloxane functionalized polyolefin having multiple reaction sites, characterized in that: The general structure is as follows: Where: R z Selected from α-olefins containing 3 to 20 carbon atoms 、 One or more of cyclic olefins and non-conjugated dienes; R n Selected from CH3, One of; x is selected from natural numbers ranging from 1 to 100, y is selected from natural numbers ranging from 500 to 2000, z is selected from natural numbers ranging from 1 to 100, n is selected from natural numbers ranging from 1 to 32, and m is selected from natural numbers ranging from 32 to 200.

2. The polysiloxane functionalized polyolefin having multiple reaction sites according to claim 1, characterized in that: In the polysiloxane functionalized polyolefin: The molecular weight of the polysiloxane chain segment is: 1.3-19.0 kg / mol; The mass content of the polysiloxane monomer is 1 to 55%, and the mass content of the third monomer is 0.5 to 28%; The weight average molecular weight is 80-300 kg / mol.

3. The polysiloxane functionalized polyolefin having multiple reaction sites according to claim 1, characterized in that: In the polysiloxane functionalized polyolefin: The α-olefin containing 3 to 20 carbon atoms is selected from The cyclic olefin is selected from The non-conjugated diene is selected from 4. A method for preparing a polysiloxane functionalized polyolefin having multiple reaction sites according to any one of claims 1 to 3, characterized in that: include: (1) using hydrogen-containing silane and siloxane ring as raw materials, preparing a double-terminal hydrogen-containing polysiloxane macromonomer through cationic ring-opening polymerization; (2) using vinyl norbornene and the double-terminated hydrogen-containing polysiloxane macromonomer prepared in step (1) as raw materials, and obtaining a norbornene-based double-terminated polysiloxane macromonomer through a hydrosilylation reaction; (3) Coordination copolymerization of the norbornene-based double-terminated polysiloxane macromonomer prepared in step (2) with ethylene and a third monomer to obtain the polysiloxane functionalized polyolefin having multiple reaction sites.

5. The method for preparing a polysiloxane functionalized polyolefin having multiple reaction sites according to claim 4, characterized in that: In step (1): The siloxane ring body is selected from octamethylcyclotetrasiloxane, 1,3,5-trimethyl-1,3,5-tris(3,3,3-trifluoropropyl)cyclotrisiloxane, 2,2,4,6,6,8-hexamethyl-4,8-diphenylcyclotetrasiloxane, or a side chain functionalized siloxane ring body having the structural formula (II-1) to (II-3) as shown below; The hydrogen-containing silane is selected from 1,1,3,3-tetramethyldisiloxane; The molar ratio of the hydrogen-containing silane to the siloxane ring is 1:(8-50); The cationic ring-opening polymerization is specifically: The acid catalyst, the siloxane-containing ring body and the hydrogen-containing silane are uniformly mixed, and a cationic ring-opening polymerization is initiated at 0 to 85° C. to obtain a double-terminal hydrogen-containing polysiloxane; The acid catalyst is selected from one or more of activated clay, trifluoroacetic acid and concentrated sulfuric acid.

6. The method for preparing a polysiloxane functionalized polyolefin having multiple reaction sites according to claim 4, characterized in that: In step (2): The molar ratio of vinyl norbornene to the double-terminal hydrogen-containing polysiloxane macromonomer is (3-15):1; The hydrosilylation reaction is carried out under the action of a catalyst at a reaction temperature of 50 to 100°C.

7. The method for preparing a polysiloxane functionalized polyolefin having multiple reaction sites according to claim 4, characterized in that: In step (3), the coordination copolymerization specifically comprises: Take a reaction device equipped with a sealed mechanical stirring device, replace the reaction system with an inert ethylene atmosphere without water and oxygen; then add a solvent, and add a co-catalyst, a norbornene-based double-terminated polysiloxane macromonomer, a third monomer and an activator in sequence, and then add a catalyst to initiate a polymerization reaction, and keep the ethylene pressure constant during the reaction. After the polymerization reaction is completed, the crude product is post-treated to obtain the polysiloxane functionalized polyolefin; The molar ratio of the norbornene-dicapped polysiloxane macromonomer to the third monomer is 1:(1-100); The initial concentration of the norbornene-dicapped polysiloxane macromonomer in the reaction system is controlled to be (0.5-20) mmol / L; Control the pressure in the reaction system to 0.1-1.0 MPa; The temperature of the coordination copolymerization is 0 to 70°C.

8. An EPDM rubber / silicone rubber blend, characterized in that: The polysiloxane functionalized polyolefin with multiple reaction sites as claimed in any one of claims 1 to 3 is used as a compatibilizer.

9. The EPDM rubber / silicone rubber blend according to claim 8, characterized in that: The raw material composition includes, by mass:

10. The EPDM rubber / silicone rubber blend according to claim 8, characterized in that: In the polysiloxane functionalized polyolefin: R z Selected from and / or or and At least one of combination of; R n Selected from CH3, The molecular weight of the polysiloxane chain segment is 6.1-18.6 kg / mol; the mass content of the polysiloxane monomer is 17-55%.

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