A polysiloxane-functionalized polyolefin having multiple reaction sites, and a method of making and use thereof

Abstract

The application discloses a polysiloxane functionalized polyolefin with multiple reaction sites, and a general structure is as follows: wherein R z is selected from one or more of alpha-olefins, cyclic olefins and non-conjugated dienes containing 3-20 carbon atoms; R n is selected from one of CH3, and x is a natural number selected from 1-100, y is a natural number selected from 500-2000, z is a natural number selected from 1-100, n is a natural number selected from 1-32, and m is a natural number selected from 32-200. The polysiloxane functionalized polyolefin disclosed by the application is used as a compatilizer for preparing an ethylene-propylene-diene rubber / silicone rubber blend, the compatibility of the ethylene-propylene-diene rubber and the silicone rubber can be significantly improved, and the mechanical strength and heat resistance of the ethylene-propylene-diene rubber / silicone rubber blend are significantly enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rubber blending, in particular to a polysiloxane functionalized polyolefin with multiple reaction sites, a preparation method thereof and application thereof in preparing EPDM / SR blends. BACKGROUND

[0002] EPDM is a copolymer of ethylene, propylene and a third monomer, which has excellent electrical insulation and aging resistance, and is widely used in the fields of electric wires and cables, automobile components, etc. However, its heat resistance is limited. Silicone rubber has excellent high and low temperature resistance and weather resistance, and is widely used in the fields of aerospace and power, but its mechanical properties are weak and its cost is high.

[0003] Therefore, it is desirable to blend EPDM and silicone rubber to integrate the excellent mechanical properties of EPDM and the excellent heat resistance of silicone rubber, so as to obtain a comprehensive composite material. The challenge is that the compatibility of the two is poor because the main chain of EPDM is composed of C-C bonds, while the main chain of silicone rubber is composed of Si-O bonds. At the same time, the differences in viscosity and vulcanization speed of the two kinds of rubber also increase the difficulty of preparing excellent blends.

[0004] A compatibilizer is disclosed in Chinese patent document CN109867789A, which is prepared from liquid EPDM, hydrogen-containing silicone oil and catalyst, and is used to improve the compatibility of EPDM and silicone rubber, and to improve the physical and mechanical properties and heat and aging resistance of the blend. However, the structure of the compatibilizer is not clear, and the compatibilization effect is not obvious. The maximum increase in tensile strength and elongation at break of the blend is only 8.4% and 11.5%, respectively, and the improvement in mechanical properties is limited, and the improvement in aging performance is also not obvious.

[0005] Kole (S. Kole, S. Roy, A.K. Bhowmick, 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 to SR and the introduction of maleic anhydride / maleic acid into EPDM, and the compatibility between EPDM and SR was enhanced by the interaction between the introduced carboxyl and amide groups. However, this method requires modification of the base material before introducing the reactive compatibilizer.

[0006] Ashokrao (C. Ashokrao Fuke, P. Anna Mahanwar, S., Modified ethylene-propylene-diene elastomer (EPDM)-contained silicone rubber / ethylene-propylene-diene elastomer (EPDM) blends: Effect of composition and electronbeam crosslinking on mechanical, heat shrinkability, electrical, and morphological properties, J. Appl. Polym. Sci. 136(29) (2019) 47787.) et al. reported that methyl methacrylate (MAA) grafted EPDM as a compatibilizer induced by gamma radiation, the grafted EPDM improved the crosslinking degree, thus significantly improved the mechanical properties of EPDM / silicone rubber blend during vulcanization. However, the structural similarity leads to the crosslinking sites mainly concentrated in the EPDM phase, which may impair the compatibility to some extent.

[0007] It can be seen that the compatibilizers for blending EPDM and silicone rubber disclosed in the prior art either have general compatibilization effect or need complex substrate regulation process, resulting in high cost. Therefore, this study has important value and academic significance for preparing high-performance EPDM / silicone rubber blend. SUMMARY

[0008] In view of the above problems existing in the prior art, the present application discloses a polysiloxane functionalized polyolefin with multiple reaction sites, which has a novel structure and has 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 / silicone rubber blend.

[0009] The specific technical solutions are as follows:

[0010] A polysiloxane functionalized polyolefin with multiple reaction sites, the general structure is as follows:

[0011] (I);

[0012] In the formula: R z selected from one or more of α-olefins, cyclic olefins, and non-conjugated dienes containing 3-20 carbon atoms;

[0013] Rn one selected from CH3、 、 、 、 、 ;

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

[0015] The polysiloxane functionalized polyolefin disclosed in the application is a ternary copolymer comprising ethylene, a norbornene-based bis-terminated polysiloxane and a third monomer, and has mechanical properties and can be used as a vulcanized rubber body. The weight average molecular weight, the polysiloxane monomer content in the copolymer and the molecular weight of the polysiloxane macromonomer of the polysiloxane functionalized polyolefin can be adjusted in a wide range. In particular, the polysiloxane functionalized polyolefin has multiple reaction sites and can be used as a compatibilizer for preparing a ternary ethylene propylene rubber / silicone rubber blend, and by adjusting the above parameters, it tends to be stable at the phase interface of the ternary ethylene propylene rubber and the silicone rubber during the blending process, significantly improving the mechanical properties, especially the tensile strength and tear strength, and the heat aging resistance of the ternary ethylene propylene rubber / silicone rubber blend.

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

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

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

[0019] Preferably, in the polysiloxane functionalized polyolefin:

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

[0021] The cyclic olefin is selected from ;

[0022] The non-conjugated diene is selected from 、 or .

[0023] The application also discloses a preparation method of the polysiloxane functionalized polyolefin with multiple reaction sites, comprising:

[0024] (1) using a hydrogen-containing silane and a siloxane ring as raw materials, a double-end hydrogen-containing polysiloxane macromonomer is prepared by cationic ring-opening polymerization;

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

[0026] (3) using the norbornene-terminated polysiloxane macromonomer prepared in step (2) and ethylene, a third monomer, the polysiloxane-functionalized polyolefin having multiple reaction sites is prepared by coordination copolymerization.

[0027] The preparation method disclosed in the application comprises three steps of cationic ring-opening polymerization, hydrosilylation and coordination copolymerization, and the polysiloxane monomer content and the molecular weight of the polysiloxane macromonomer in the prepared polysiloxane-functionalized polyolefin can be accurately controlled by adjusting the molar ratio of the hydrogen-containing silane to the siloxane ring in the cationic ring-opening polymerization and the feeding molar concentration of the norbornene-terminated polysiloxane macromonomer in the coordination copolymerization.

[0028] In step (1),

[0029] The siloxane ring is selected from octamethylcyclotetrasiloxane or a side-chain functionalized siloxane ring shown in the following formula (II-1)~(II-3);

[0030] (II-1); (II-2); (II-3);

[0031] Among them, octamethylcyclotetrasiloxane, 1,3,5-trimethyl-1,3,5-tris(3,3,3-trifluoropropyl)cyclotrisiloxane, 2,2,4,6,6,8-hexamethyl-4,8-diphenylcyclotetrasiloxane can be obtained by a commercial route; and the side-chain functionalized siloxane ring shown in formula (II-1)~(II-3) is synthesized by oneself.

[0032] The side-chain functionalized siloxane ring is prepared by a hydrolysis reaction, and the preparation of the side-chain functionalized siloxane ring of formula (II-1) is as follows: dimethyldichlorosilane and methylvinyl dichlorosilane are used as raw materials, hydrolysis reaction is carried out in constant-boiling hydrochloric acid, and a surfactant is added to prepare the side-chain functionalized siloxane ring;

[0033] Specifically, it comprises:

[0034] In a three-necked flask equipped with a condenser, first add constant boiling hydrochloric acid, then add surfactant and stir until completely dissolved, then mix dimethyldichlorosilane and methylvinyldichlorosilane uniformly, and then dropwise add at 30-60℃ through a micro-feeding pump to carry out the reaction; after the reaction is completed, extract, separate and distill under reduced pressure to obtain the side chain functionalized siloxane ring body of formula (II-1).

[0035] Preferably,

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

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

[0038] If the side chain functionalized siloxane ring body shown in formula (II-2)~(II-3) is prepared, the following preparation method is used:

[0039] In a three-necked flask equipped with a condenser, first add constant boiling hydrochloric acid, then add surfactant and stir until completely dissolved, then mix dimethyldichlorosilane and methylvinyldichlorosilane uniformly, and then dropwise add at 30-60℃ through a micro-feeding pump to carry out the reaction; after the reaction is completed, extract, separate and distill under reduced pressure to obtain the side chain functionalized siloxane ring body of formula (II-1).

[0040] Preferably,

[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℃.

[0044] The hydrosilylation reaction also needs to add a catalyst, which is specifically selected from common catalysts in the art, such as Karstedt catalyst, chloroplatinic acid, etc.

[0045] In step (1),

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

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

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

[0049] Further preferably, the molar ratio of the hydrogen-containing silane to the cyclic siloxane is 1: (16-32).

[0050] Most preferably, the molar ratio of the hydrogen-containing silane to the cyclic siloxane 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 accurately controlled by adjusting the above parameters, and with continuous optimization of the above parameters, the mechanical properties and aging resistance of the EPDM / silicone rubber blend prepared by using the polysiloxane functionalized polyolefin prepared by the present application as a compatibilizer are continuously improved.

[0052] In step (1) :

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

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

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

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

[0057] Preferably, the temperature of the cationic ring-opening polymerization is 50-80℃, and further preferably is 65-75℃.

[0058] Preferably, the crude product obtained by the cationic ring-opening polymerization also needs to be filtered and distilled under reduced pressure.

[0059] In step (2) :

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

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

[0062] The silicon-hydrogen addition reaction is carried out in the presence of a catalyst, and the reaction temperature is 50-100℃.

[0063] Preferably, the catalyst is selected from the common types of catalysts for silicon-hydrogen addition reactions, such as Karstedt's catalyst or chloroplatinic acid.

[0064] Preferably, the temperature of the silicon-hydrogen addition reaction is 80-90℃, and further preferably is 85℃.

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

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

[0067] The reaction system is replaced with anhydrous and anaerobic inert ethylene atmosphere in a reaction device equipped with a sealed mechanical stirring device; then the solvent is added, and the cocatalyst, the norbornene-terminated polysiloxane macromonomer, the third monomer and the activator are sequentially added; then the catalyst is added to initiate the polymerization reaction, and the ethylene pressure is kept constant during the reaction; after the polymerization reaction is completed, the crude product is treated to obtain the polysiloxane functionalized polyolefin;

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

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

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

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

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

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

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

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

[0076] The pressure in the reaction system is controlled to be 0.1-1.0 MPa;

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

[0078] Further 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 the coordination copolymerization is 0-70℃;

[0081] Preferably, the temperature of the coordination copolymerization is 10-30℃, and the time is 5-30min.

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

[0083] The types of the solvent, the cocatalyst and the activator are not particularly limited, and are selected from the commonly used types in the art. For example, the solvent is selected from anhydrous toluene, anhydrous n-hexane, an isoparaffin solvent (Isopar series), etc., the cocatalyst is selected from diethyl aluminum chloride, and the activator is selected from ethyl trichloroacetate.

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

[0085] The application also discloses a three-component ethylene-propylene rubber / silicone rubber blend, which uses the polysiloxane functionalized polyolefin with multiple reaction sites as a compatibilizer.

[0086] Preferably, the raw material composition of the three-component ethylene-propylene rubber / silicone rubber blend includes, by mass fraction:

[0087] Three-component ethylene-propylene rubber 10-90 parts;

[0088] Silicone rubber 10-90 parts;

[0089] Compatibilizer 0.5-6 parts;

[0090] Vulcanizing agent 1-3 parts;

[0091] Vulcanizing aid 1-5 parts.

[0092] Preferably, in the polysiloxane functionalized polyolefin:

[0093] R z is selected from and / or , or is and , and ;

[0094] R n is selected from CH3, or ;

[0095] The molecular weight of the polysiloxane segment is 6.1-18.6 kg / mol, and the mass content of the polysiloxane monomer is 17-55%.

[0096] It is found through experiments that the prepared EPDM / silicone rubber blend has higher mechanical properties and better aging resistance when the polysiloxane functionalized polyolefin with the above preferred structure is used as the compatibilizer.

[0097] Preferably, the vulcanizing agent is selected from 2,5-dimethyl-2,5-bis-hexane and / or dicumyl peroxide;

[0098] Preferably, the vulcanizing aid is selected from one or more of zinc oxide, stearic acid, and silicone oil.

[0099] Preferably, the raw materials can further include a reinforcing agent, such as nano-silica and / or carbon black.

[0100] Further preferably, the raw material composition of the EPDM / silicone rubber blend includes, by mass fraction:

[0101] 50-80 parts of EPDM;

[0102] 20-50 parts of silicone rubber;

[0103] 2-6 parts of compatibilizer;

[0104] 1-3 parts of vulcanizing agent;

[0105] 1-5 parts of vulcanizing aid.

[0106] More preferably, the mass fraction of the compatibilizer is 2-4 parts.

[0107] Compared with the prior art, the present application has the following beneficial effects:

[0108] The present application discloses a polysiloxane functionalized polyolefin with a novel structure, which is a multi-copolymer including ethylene, a norbornene-based bis-terminated polysiloxane, and a third monomer, and has mechanical properties and can be used as a vulcanized rubber body.

[0109] The present application also discloses a preparation method of the polysiloxane functionalized polyolefin, and through accurate control of process parameters, the weight average molecular weight of the copolymer, the polysiloxane monomer content in the copolymer, and the molecular weight of the polysiloxane macromonomer can be adjusted in a large range.

[0110] The polysiloxane functionalized polyolefin disclosed by the present application has multiple reaction sites, can be used as a compatibilizer to prepare an EPDM / silicone rubber blend, and through adjustment of parameters, tends to be stable at the phase interface of the EPDM and the silicone rubber in the blending process, significantly improves the mechanical properties, especially the tensile strength and tear strength, and the heat aging resistance of the EPDM / silicone rubber blend. BRIEF DESCRIPTION OF DRAWINGS

[0111] Figure 1 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 1 prepared in Example 1;

[0112] Figure 2 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 1 prepared in Example 1;

[0113] Figure 3 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 7 prepared in Example 7;

[0114] Figure 4 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 8 prepared in Example 8;

[0115] Figure 5 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 9 prepared in Example 9;

[0116] Figure 6 Nuclear magnetic resonance hydrogen spectrum of siloxane ring prepared in Examples 12, 13, 14, respectively;

[0117] Figure 7 Nuclear magnetic resonance hydrogen spectrum of norbornene double-terminated side chain functionalized polysiloxane macromer prepared in Examples 12, 13, 14, respectively, and norbornene single-terminated polysiloxane macromer prepared in Comparative Example 3;

[0118] Figure 8 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 12 prepared in Example 12;

[0119] Figure 9 High temperature nuclear magnetic resonance hydrogen spectrum of compatibilizer 13 prepared in Example 13;

[0120] Figure 10 TEM images of ethylene propylene diene rubber / silicone rubber blend prepared in Example 13 and Comparative Example 2, respectively;

[0121] Figure 11 High temperature nuclear magnetic resonance hydrogen spectrum of product prepared in Comparative Example 3. DETAILED DESCRIPTION

[0122] For further purposes of illustrating the present application, the technical solutions and advantages thereof, the present application will be further described in detail below with specific examples, but the protection scope of the present application shall not be limited thereby.

[0123] The ethylene propylene diene rubber and the silicone rubber are both commercially available, the ethylene propylene diene rubber (Dow Chemical Group, 4725P); the vinyl silicone rubber (Hesheng Silicone Industry, vinyl content 0.22 mol%).

[0124] Example 1

[0125] (1) 0.75 g activated clay, 23.7 g octamethylcyclotetrasiloxane (0.08 mol) and 1.34 g 1,1,3,3-tetramethyldisiloxane (0.01 mol) were added into a 100 mL flask under nitrogen atmosphere; after reaction at 65 °C for 14 h, the catalyst was removed by filtration, and the unreacted raw materials were removed by distillation under reduced pressure (95 °C, 5 kPa) to obtain colorless transparent di-terminal hydrogen-containing polysiloxane;

[0126] (2) 1.2 g of vinyl norbornene (0.1 mol) and Karstedt catalyst (Pt: 1.2 μmol) were added into a round-bottom flask under nitrogen atmosphere, and then 23 g (0.01 mol) of di-terminal hydrogen-containing polysiloxane prepared in step (1) was added dropwise; after reaction at 85 °C for 24 h, the unreacted vinyl norbornene was removed by distillation under reduced pressure (95 °C, 5 kPa) to obtain colorless transparent norbornenyl di-block terminated polysiloxane macromer, and the number average molecular weight of the norbornenyl di-block terminated polysiloxane macromer was determined to be 3.2 kg / mol by GPC analysis;

[0127] (3) A 250 mL glass reactor was vacuumed for 10 min, and then filled with ethylene 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 20 mmol / L) and norbornenyl di-block terminated polysiloxane macromer (0.94 g, 0.375 mmol, initial concentration 5 mmol / L) prepared in step (2) were added, respectively. After stirring for 5 min, 1 μmol VCl3(THF)3was injected to initiate the reaction, and ethylene gas was constantly filled to maintain the system pressure at 0.1 MPa during the reaction. After a period of time, the reaction was poured into acidic ethanol for precipitation, the filter cake was washed with a mixture of anhydrous ethanol and tetrahydrofuran (3:1) for three times, and vacuum dried at 60 °C for 12 h to obtain 1.1 g of white solid product as a polysiloxane functionalized polyolefin with multiple reaction sites, which was denoted as compatibilizer 1;

[0128] (4) 70 parts by mass of ethylene-propylene-diene rubber, 30 parts by mass of silicone rubber and 2 parts by mass of the compatibilizer synthesized in step (3) were added into an internal mixer and mixed at 100 °C for 5 min;

[0129] (5) 30 parts by mass of nano-silicon dioxide and 3 parts by mass of zinc oxide were further added into the internal mixer and mixed for 10 min, and then 1.2 parts by mass of 2,5-dimethyl-2,5-bis-hexane was added, and the mixture was further mixed for 5 min before discharging;

[0130] (6) After 24 h, the rubber was hot-pressed and vulcanized at 180 °C, and then the mechanical test and thermal aging test were carried out.

[0131] Figure 1 The nuclear magnetic resonance hydrogen spectrum of the double-end hydrogen-containing polysiloxane prepared in step (1) and the norbornene double-terminated polysiloxane macromonomer prepared in step (2) of the present embodiment.

[0132] Figure 2 The high-temperature nuclear magnetic resonance hydrogen spectrum of the compatibilizer 1 prepared in the present embodiment, according to which, the compatibilizer 1 is a terpolymer of ethylene / norbornene double-terminated polysiloxane / 5-ethylidene-2-norbornene, and the structural formula is as shown below:

[0133]

[0134] It was tested that the polymerization activity of the compatibilizer 1 prepared in the present embodiment was as high as 7.4 x 10 6 g / (mol·h). The number average molecular weight of the polysiloxane side chain in the copolymer was 3.2 kg / mol, the content of polysiloxane was 14.1 wt%, and the content of the third monomer 5-ethylidene-2-norbornene was 3.3 wt%. It was determined by GPC analysis that the weight average molecular weight of the compatibilizer was 93 kg / mol. Further, the differential scanning calorimeter (Q2500, TA) was used to characterize the crystallization temperature and melting temperature of the compatibilizer, and the test results are shown in Table 1.

[0135] Example 2

[0136] The preparation process is basically the same as that in Example 1, and the difference lies in that:

[0137] In step (1), the addition amount of octamethylcyclotetrasiloxane was replaced by 37.9 g (0.128 mol), and the addition amount of 1,1,3,3-tetramethyldisiloxane was replaced by 1.07 g (0.008 mol);

[0138] In step (2), the addition amount of vinyl norbornene was replaced by 7.4 g (0.062 mol), and the addition amount of double-end hydrogen-containing polysiloxane was replaced by 32.2 g (0.0062 mol);

[0139] In step (3), the addition amount of norbornene double-terminated polysiloxane was replaced by 1.95 g (0.375 mmol, initial concentration of 5 mmol / L).

[0140] The polysiloxane functionalized polyolefin prepared in the present embodiment is denoted as compatibilizer 2, and the various performance parameters are listed in Table 1 below.

[0141] Example 3

[0142] The preparation process is basically the same as in Example 1, except that:

[0143] In step (1), the addition amount of octamethylcyclotetrasiloxane is replaced by 37.9 g (0.128 mol), and the addition amount of 1,1,3,3-tetramethyldisiloxane is replaced by 0.54 g (0.004 mol);

[0144] In step (2), the addition amount of vinyl norbornene is replaced by 4.8 g (0.04 mol), and the addition amount of hydrogen-containing polysiloxane with both ends is replaced by 42.8 g (0.004 mol);

[0145] In step (3), the addition amount of norbornene-terminated polysiloxane is replaced by 4.0 g (0.375 mmol, initial concentration of 5 mmol / L).

[0146] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 3, and the performance parameters are listed in Table 1 below.

[0147] Example 4

[0148] The preparation process is basically the same as in Example 1, except that:

[0149] In step (1), the addition amount of octamethylcyclotetrasiloxane is replaced by 37.9 g (0.128 mol), and the addition amount of 1,1,3,3-tetramethyldisiloxane is replaced by 0.34 g (0.0026 mol);

[0150] In step (2), the addition amount of vinyl norbornene is replaced by 2.4 g (0.02 mol), and the addition amount of hydrogen-containing polysiloxane with both ends is replaced by 29.2 g (0.002 mol);

[0151] In step (3), the addition amount of norbornene-terminated polysiloxane is replaced by 5.6 g (0.375 mmol, initial concentration of 5 mmol / L).

[0152] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 4, and the performance parameters are listed in Table 1 below.

[0153] Example 5

[0154] The preparation process is basically the same as in Example 3, except that the addition amount of norbornene-terminated polysiloxane added in step (3) is replaced by 0.8 g (0.075 mmol, initial concentration of 1 mmol / L).

[0155] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 5, and the performance parameters are listed in Table 1 below.

[0156] Example 6

[0157] The preparation process is basically the same as that in Example 3, except that the added amount of the norbornene-based double-terminated polysiloxane in step (3) is replaced by 8.1 g (0.756 mmol, initial concentration of 10 mmol / L).

[0158] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 6, and the performance parameters are listed in Table 1 below.

[0159] Example 7

[0160] The preparation process is basically the same as that in Example 3, except that the third monomer 5-ethylidene-2-norbornene in step (3) is replaced by an equal molar amount of dicyclopentadiene.

[0161] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 7, and the performance parameters are listed in Table 1 below.

[0162] Figure 3 The high-temperature nuclear magnetic resonance hydrogen 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 as shown below:

[0163]

[0164] Example 8

[0165] The preparation process is basically the same as that in Example 3, except that the third monomer 5-ethylidene-2-norbornene in step (3) is replaced by an equal molar amount of dicyclopentadiene.

[0166] The polysiloxane functionalized polyolefin prepared in this example is denoted as compatibilizer 7, and the performance parameters are listed in Table 1 below.

[0167] Figure 4 The high-temperature nuclear magnetic resonance hydrogen 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 as shown below:

[0168]

[0169] Example 9

[0170] Steps (1)-(2) are the same as in Example 3.

[0171] (3) A 250 mL glass reactor was evacuated for 10 min and then filled with ethylene to maintain the system pressure at 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), 5-ethylidene-2-norbornene (1.125 mmol, initial concentration 20 mmol / L), and norbornyl-terminated polysiloxane macromer (4.0 g, 0.375 mmol, initial concentration 5 mmol / L) prepared in step (2) were added, respectively, and the reaction was initiated by injecting 1 μmol VCl3(THF)3 after stirring for 5 min. During the reaction, ethylene / propylene mixed gas was continuously filled to maintain the system pressure at 0.1 MPa, and the molar ratio of ethylene to propylene was 1:3. After a period of time, the reaction was poured into acidic ethanol for precipitation, the filter cake was washed with a mixture of anhydrous ethanol:tetrahydrofuran = 3:1 for three times, and vacuum dried at 60°C for 12 h to obtain 1.2 g of white solid product, which was denoted as compatibilizer 9.

[0172] Steps (4)-(6) were the same as in Example 3.

[0173] The compatibilizer 9 prepared in this example had the performance parameters listed in Table 1 below.

[0174] Figure 5 The high-temperature nuclear magnetic resonance hydrogen spectrum of the compatibilizer prepared in this example showed that the compatibilizer 9 was a tetrad copolymer of ethylene / propylene / 5-ethylidene-2-norbornene / norbornyl-terminated polysiloxane, and the structural formula was as shown below:

[0175]

[0176] Example 10

[0177] The preparation process was basically the same as in Example 3, except that the reaction solvent added in step (3) was replaced by anhydrous n-hexane.

[0178] The polysiloxane functionalized polyolefin prepared in this example was denoted as compatibilizer 10, and the performance parameters were listed in Table 1.

[0179] Example 11

[0180] The preparation process was basically the same as in Example 3, except that in step (3), the pressure of the reaction system was maintained at 0.5 MPa by filling ethylene.

[0181] The polysiloxane functionalized polyolefin prepared in this example was denoted as compatibilizer 11, and the performance parameters were listed in Table 1.

[0182] Example 12

[0183] (1) Under nitrogen atmosphere, 150 mL of constant boiling hydrochloric acid was added into a 250 mL three-necked flask equipped with a condenser, and 0.8 g (3.7 mmol) of sodium octane sulfonate was added and stirred until completely dissolved. Then 38.6 g (0.3 mol) of dimethyl dichlorosilane and 14.1 g (0.1 mol) of methyl vinyl dichlorosilane were mixed uniformly and added dropwise into the three-necked flask at 30°C (100 mL / min). After the dropwise addition was completed, the stirring was continued for 10 min. After extraction and separation, anhydrous calcium chloride was added and stirred for 12 h. After filtration, the fraction of 100-130°C was collected by distillation under reduced pressure at 5 kPa to obtain a colorless transparent siloxane mixed ring containing vinyl group in the side chain.

[0184] The nuclear magnetic resonance hydrogen spectrum of the siloxane mixed ring containing vinyl group in the side chain prepared in this example is shown in FIG. 1. Figure 6 As can be seen from the figure, the structural formula of the siloxane ring prepared in this example is as follows:

[0185] .

[0186] (2) Under nitrogen atmosphere, 0.75 g of activated clay, 23.7 g of the siloxane mixed ring containing vinyl group in the side chain prepared in step (1) (0.08 mol) and 0.34 g of 1,1,3,3-tetramethyldisiloxane (2.5 mmol) were added into a 100 mL flask. After reaction at 75°C for 14 h, the catalyst was removed by filtration, and the unreacted raw materials were removed by distillation under reduced pressure (95°C, 5 kPa) to obtain a colorless transparent hydrogen-terminated polysiloxane containing vinyl group in the side chain. The number average molecular weight of the hydrogen-terminated polysiloxane containing vinyl group in the side chain was 11.2 kg / mol as determined by GPC analysis.

[0187] (3) Under nitrogen atmosphere, 1.2 g of vinyl norbornene (0.01 mol) and Karstedt catalyst (Pt: 1.2 μmol) were added into a round-bottom flask, and then 11.2 g (1 mmol) of the hydrogen-terminated polysiloxane prepared in step (2) was added dropwise. After reaction at 85°C for 24 h, the unreacted vinyl norbornene was removed by distillation under reduced pressure (95°C, 5 kPa) to obtain a colorless transparent norbornene-terminated polysiloxane macromonomer containing vinyl group in the side chain. The number average molecular weight of the norbornene-terminated polysiloxane macromonomer containing vinyl group in the side chain was 11.4 kg / mol as determined by GPC analysis.

[0188] The nuclear magnetic resonance hydrogen spectrum of the norbornene-terminated polysiloxane macromonomer containing vinyl group in the side chain prepared in this example is shown in FIG. 3. Figure 7 As can be seen from the figure, the structural formula of the norbornene-terminated polysiloxane macromonomer containing vinyl group in the side chain prepared in this example is as follows:

[0189] .

[0190] (4) A 250 mL glass reactor was evacuated for 10 min and then charged with ethylene to maintain a system pressure of 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), 5-ethylidene-2-norbornene (1.125 mmol, initial concentration 20 mmol / L), and norbornyl-terminated polysiloxane macromer (4.3 g, 0.375 mmol, initial concentration 5 mmol / L) prepared in step (3) were added successively, and after stirring for 5 min, 1 μmol VCl3(THF)3was injected to initiate the reaction, and ethylene gas was continuously charged to maintain a system pressure of 0.1 MPa during the reaction. After a period of time, the reaction was poured into acidic ethanol for precipitation, the filter cake was washed with a mixture of anhydrous ethanol and tetrahydrofuran (3:1) three times, and dried at 60°C under vacuum for 12 h to obtain 0.39 g of white solid product, which was denoted as compatibilizer 12, and the performance parameters are listed in Table 1 below.

[0191] Steps (5) to (7) were the same as in Example 3.

[0192] Figure 8 The high-temperature nuclear magnetic resonance hydrogen spectrum of the compatibilizer prepared in this example showed that the compatibilizer 12 was a terpolymer of ethylene / norbornyl-terminated polysiloxane macromer containing vinyl groups in the side chain / 5-ethylidene-2-norbornene, and the theoretical structural formula was as shown below:

[0193] .

[0194] Example 13

[0195] (1) In a 250 mL three-necked flask equipped with a condenser under nitrogen atmosphere, 150 mL of constant boiling hydrochloric acid was added, and 0.8 g (3.7 mmol) of sodium octane sulfonate was added and stirred until completely dissolved. Then, 38.6 g (0.3 mol) of dimethyl dichlorosilane and 11.5 g (0.1 mol) of methyl dichlorosilane were mixed uniformly and added dropwise into the three-necked flask at 30°C (100 mL / min). After the dropwise 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 of 100-115°C was collected by distillation under reduced pressure to obtain a colorless transparent siloxane mixed ring containing a hydrogen-containing side chain. Then, 100 mL of the flask was replaced with a nitrogen atmosphere, 27.5 g of ethylidene norbornene and Karstedt catalyst (Pt: 1.2 μmol) were added, and 12.5 g of the above prepared siloxane mixed ring containing a hydrogen-containing side chain was added dropwise at 80°C at a rate of 0.5 mL / min. After the dropwise addition was completed, the reaction was continued for 24 h. Then, the unreacted starting material was removed by distillation under reduced pressure (85°C, 5 kPa) to obtain a colorless transparent siloxane mixed ring containing an ethylidene norbornene group in the side chain.

[0196] The hydrogen nuclear magnetic resonance spectrum of the siloxane mixed ring containing an ethylidene norbornene group in the side chain prepared in this example is shown in FIG. 1. Figure 6 As can be seen from the figure, the structural formula of the siloxane ring prepared in this example is as follows:

[0197] .

[0198] Steps (2)-(7) are the same as in Example 3.

[0199] The hydrogen nuclear magnetic resonance spectrum of the siloxane mixed ring containing an ethylidene norbornene group in the side chain prepared in this example is shown in FIG. 1. Figure 7 As can be seen from the figure, the structural formula of the siloxane ring prepared in this example is as follows:

[0200] .

[0201] The polyolefin functionalized with siloxane prepared in this example is referred to as compatibilizer 13, and the performance parameters are listed in Table 1 below.

[0202] Figure 9 The high temperature hydrogen nuclear magnetic resonance spectrum of the compatibilizer prepared in this example is shown in FIG. 1. As can be seen from the figure, the compatibilizer 13 is a terpolymer of ethylene / siloxane mixed ring containing an ethylidene norbornene group in the side chain / norbornene double-terminated polysiloxane macromer / 5-ethylene-2-norbornene, and the structural formula is as shown below:

[0203] .

[0204] Figure 10 The TEM images of the ethylene / ethylidene norbornene / silicone rubber terpolymer prepared in this example are shown in Figure 6, along with the TEM images of the ethylene / ethylidene norbornene / silicone rubber terpolymer prepared in Comparative Example 2 for comparison. In the TEM images, the grey irregular regions correspond to the silicone rubber phase, the lighter regions correspond to the ethylene / ethylidene norbornene rubber phase, and the dark spots are the ZnO particles. In Comparative Example 2, larger phase sizes were observed, which means that the ethylene / ethylidene norbornene rubber and the silicone rubber were incompatible. After the addition of compatibilizer 13, the phase sizes of both the ethylene / ethylidene norbornene rubber and the silicone rubber regions were observed to decrease, indicating that the compatibility was improved.

[0205] Example 14

[0206] The preparation process was substantially the same as in Example 13, except that the monomer added in the post-treatment hydrosilylation step (1) was replaced with 4-vinyl-1-cyclohexene in an equal molar amount.

[0207] The proton nuclear magnetic resonance spectrum of the silicone mixed cyclic body prepared in this example, which contains 4-vinyl-1-cyclohexene in the side chain, is shown in Figure 6. Figure 6 As can be seen from the figure, the structure is as follows:

[0208] ;

[0209] The proton nuclear magnetic resonance spectrum of the norbornene-based double-terminated side-chain functionalized polysiloxane macromer prepared in this example is shown in Figure 7. Figure 7 As can be seen from the figure, the structure is as follows:

[0210] .

[0211] The polysiloxane functionalized polyolefin prepared in this example is referred to as compatibilizer 14, and the various performance parameters are listed in Table 1 below.

[0212] The compatibilizer 14 prepared in this example: ethylene / norbornene-based double-terminated polysiloxane macromer containing cyclohexene-based side chains / 5-ethylidene-2-norbornene terpolymer, the theoretical structure is shown in the following formula:

[0213]

[0214] The copolymer has crosslinking, and the molecular weight and polysiloxane insertion cannot be measured.

[0215] Example 15

[0216] The preparation process was substantially the same as in Example 13, except that the amount of compatibilizer added in step (4) was replaced with 1 part by mass.

[0217] Example 16

[0218] The preparation process is basically the same as that of Example 13, except that the amount of the compatibilizer added in step (4) is replaced by 4 parts by mass.

[0219] Example 17

[0220] The preparation process is basically the same as that of Example 13, except that the amount of the compatibilizer added in step (4) is replaced by 6 parts by mass.

[0221] Comparative Example 1

[0222] (1) A 250 mL glass reactor was vacuumed for 10 min, and then filled with ethylene to keep the system pressure at 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set at 30°C, anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), and 5-ethylidene-2-norbornene (1.125 mmol, initial concentration 20 mmol / L) were added respectively, and after stirring for 5 min, 1 μmol VCl3(THF)3was injected to initiate the reaction, and ethylene gas was constantly filled to keep the system pressure at 0.1 MPa during the reaction. After a period of time, it was poured into acidic ethanol for precipitation, the filter cake was washed with anhydrous ethanol three times, and vacuum dried at 60°C for 12 h to obtain 0.95 g of white solid comparative polymer.

[0223] (2) 70 parts by mass of ethylene propylene diene rubber, 30 parts by mass of silicone rubber and 2 parts by mass of the compatibilizer synthesized in step (1) were added to the internal mixer and mixed at 100°C for 5 min.

[0224] (3) 30 parts by mass of nano-silicon dioxide and 3 parts by mass of zinc oxide were continuously added to the internal mixer and mixed for 10 min, then 1.2 parts by mass of 2,5-dimethyl-2,5-bis-hexane was added, and the mixing was continued for 5 min before discharging.

[0225] (4) After standing for 24 h, the mixed rubber was hot-pressed and vulcanized at 180°C, and then subjected to mechanical testing and thermal oxidative aging test.

[0226] The polymer prepared in this comparative example is an ethylene / 5-ethylidene-2-norbornene binary copolymer, and its performance parameters are listed in Table 1 below, and the structural formula is as shown in the following formula:

[0227]

[0228] Comparative Example 2

[0229] (1) 70 parts by mass of ethylene propylene diene rubber and 30 parts by mass of silicone rubber were added to the internal mixer and mixed at 100°C for 5 min.

[0230] (2) Continue to add 30 parts by mass of nano-silicon dioxide and 3 parts by mass of zinc oxide into the internal mixer and mix for 10 minutes, then add 1.2 parts by mass of 2,5-dimethyl-2,5-bis-hexane, continue to mix for 5 minutes, and then discharge.

[0231] (3) After placing for 24 hours, hot press and vulcanize the mixed rubber at 180°C, and then perform mechanical testing and thermal oxidative aging testing.

[0232] Comparative Example 3

[0233] (1) Under a 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 dimethylchlorosilane was added dropwise; after 24 hours of reaction, the unreacted 5-vinyl-2-norbornene was removed by rotary evaporation (95°C, 5 kPa) to obtain light yellow ethylnorbornenyl dimethylchlorosilane.

[0234] (2) Under a nitrogen atmosphere, 44.4 g (0.2 mol) of hexamethylcyclotrisiloxane was added to a round-bottom flask at 10°C, and 25 mL of tetrahydrofuran and 2 mL of n-butyllithium / hexane solution (2.4 M) were then added to initiate anionic ring-opening polymerization; after 2 hours of reaction, 1.06 g (5 mmol) of ethylnorbornenyl dimethylchlorosilane was added to cap, and norbornenyl mono-capped polysiloxane was obtained; according to GPC analysis, the number average molecular weight of the norbornenyl mono-capped polysiloxane macromer was 11.0 kg / mol.

[0235] (3) A 250 mL glass reactor was vacuumed for 10 minutes, and then was filled with ethylene to maintain a system pressure of 0.1 MPa. After repeating the operation for 6 cycles, the temperature was set to 30°C, and anhydrous toluene, Et2AlCl (2 mmol), ethyl trichloroacetate (0.15 mmol), norbornenyl mono-capped polysiloxane macromer (4.1 g, 0.375 mmol, initial concentration 5 mmol / L), and 5-ethylidene-2-norbornene (1.125 mmol, initial concentration 20 mmol / L) were added, respectively; after stirring for 5 minutes, 1 μmol of VCl3(THF)3was injected to initiate the reaction, and ethylene gas was constantly filled to maintain a system pressure of 0.1 MPa during the reaction. After a period of time, the reaction was poured into acidic ethanol for precipitation, the filter cake was washed with anhydrous ethanol three times, and was vacuum dried at 60°C for 12 hours to obtain 1.10 g of white solid polymer.

[0236] Steps (4)-(6) are the same as in Example 3.

[0237] The performance parameters of the polymer prepared in this comparative example are listed in Table 1 below.

[0238] Figure 11 A high temperature nuclear magnetic resonance hydrogen spectrum of the polymer prepared for the present comparative example was prepared and from this spectrum it was determined to be an ethylene / norbornene based mono-end capped polysiloxane / 5-ethylidene-2-norbornene terpolymer having the structure shown below:

[0239]

[0240] The performance parameters of the polysiloxane functionalized polyolefins prepared in each example and the polymer prepared in the comparative example are listed in Table 1 below.

[0241] Table 1

[0242]

[0243] The mechanical properties of the polysiloxane functionalized polyolefins prepared in each example are listed in Table 2 below.

[0244] Table 2

[0245]

[0246] Comparing the data in Table 1 and Table 2, the following conclusions can be drawn: the norbornene-terminated polysiloxane macromer shows excellent polymerization activity in copolymerization; the insertion of the norbornene-terminated polysiloxane macromer destroys the crystallization ability of the copolymer, which will reduce the mechanical properties of the copolymer to some extent; the solubility of the norbornene-terminated polysiloxane macromer in toluene is better than that in n-hexane, so the polymerization activity and molecular weight will be higher; under high pressure conditions, the concentration of gas molecules (such as ethylene and other olefin monomers) will increase significantly, according to the gas state equation, under the conditions of constant volume V and temperature T, more monomer molecules mean that the collision frequency between monomer molecules and between monomer molecules and catalyst active centers in unit time and unit volume is greatly improved, so the molecular weight and activity of the polymerization product will be higher, but since the polysiloxane macromer is a liquid, increasing the pressure has little effect on the concentration of the polysiloxane macromer, so the polysiloxane macromer insertion rate will be slightly lower; the polymerization activity of the polysiloxane macromer with a functionalized double bond in the side chain is lower than that of the polysiloxane macromer with a silicon methyl group in the side chain, wherein the compatibilizer 12 prepared in Example 12 has a vinyl group in the side chain, which is more prone to secondary reaction and contact with the active center, but since the vinyl group in the side chain is closer to the polysiloxane segment, it causes poisoning of the active center, greatly reducing the polymerization activity; the compatibilizer 13 prepared in Example 13 has a lower reactivity of the ethylidene group in the side chain, so the polymerization activity is relatively high, but the activity will still decrease; the compatibilizer 14 prepared in Example 14 has a cyclohexene group in the side chain, and the activity of the double bond in the ring is similar to that of the norbornene-terminated ring, so crosslinking occurs during copolymerization, which prevents the measurement of molecular weight and polysiloxane insertion rate.

[0247] The EPDM / silicone rubber blends prepared in each example and comparative example were subjected to tensile testing using a Zwick / Roell Z020 universal material testing machine, and the tensile rate was 50 mm / min. The results are summarized in Table 3.

[0248] Table 3

[0249]

[0250] In Table 3 above, Comparative Example 1 is a ternary ethylene-propylene rubber / silicone rubber blend modified by a copolymer without polysiloxane monomer insertion as a compatibilizer, which has poor mechanical strength, with a tensile strength and elongation at break of only 8.9 MPa and 526%, respectively, and a tear strength of only 19.5 kN / m; Comparative Example 2 is a ternary ethylene-propylene rubber / silicone rubber blend prepared by direct blending without adding any compatibilizer, which also has poor mechanical strength, with a tensile strength, elongation at break, and tear strength of only 9.5 MPa, 437%, and 18.3 kN / m, respectively; and Examples 1-17 all add the compatibilizer synthesized in the application, which all have a strong increase in tensile strength, elongation at break, and tear strength.

[0251] It can be found from Comparative Examples 1-4 that when the degree of polymerization of the polysiloxane macromonomer is about 32 (the molecular weight is about 11 kg / mol, Comparative Example 3), the compatibilizer obtained has the best improvement in compatibility, and the ternary ethylene-propylene rubber / silicone rubber blend obtained has the best mechanical properties. The reason is that when the polysiloxane side chain is short, the gel content of the polymerization product is high, which is difficult to disperse, and when the degree of polymerization of the macromonomer is about 50, the molecular weight significantly exceeds the entanglement threshold molecular weight of polysiloxane, which increases the entanglement of the polysiloxane segment and affects the compatibility.

[0252] It can be found from Comparative Examples 3, 5, and 6 that when the initial feeding concentration of the polysiloxane macromonomer is 5 mmol / L, the ternary ethylene-propylene rubber / silicone rubber blend obtained by blending the prepared compatibilizer has the best mechanical properties.

[0253] It can be found from Comparative Examples 3, 7, and 8 that when the third monomer is ethylidene norbornene, the compatibilizer obtained has the best performance. This is because in the case of an equal molar amount of the third monomer, the insertion rate of cyclopentadiene is relatively low, which cannot effectively participate in the vulcanization process, resulting in a low crosslinking density of the modified blend after vulcanization. At the same time, the norbornene structure has no extra reaction site, so the improvement in mechanical strength is also limited.

[0254] It can be found from Comparative Examples 3 and 9 that after adding propylene as a polymerization monomer, the compatibilization effect is good, and the tensile strength, elongation at break, and tear strength of the blend of Example 9 can also reach 16.6 MPa, 591%, and 27.5 kN / m, respectively. However, considering the higher cost of preparation, it is more preferred to use Compatibilizer 3.

[0255] Comparative Examples 3 and 10 show that due to the poor solubility of n-hexane for polysiloxane, the insertion rate is affected, and the performance of the compatibilizer obtained is slightly decreased.

[0256] Comparative Example 3 and 11 can find that the coordination polymerization activity is very high under higher polymerization pressure, because the solubility of ethylene in the solvent (toluene in the examples) is improved when the ethylene pressure is raised from 0.1 MPa to 0.5 MPa, and the polysiloxane macro-monomer initial concentration is kept the same, so the polysiloxane macro-monomer is relatively more difficult to diffuse to the catalytic center, so the polysiloxane insertion rate of Example 11 is less than that of Example 3, so the compatibilizer 3 is more preferred.

[0257] Comparative Examples 3, 12, 13 and 14 explore the effect of the type of reaction site of the polysiloxane side chain on the compatibilization effect of the compatibilizer, and the compatibilizer 13 is the most preferred compatibilizer, because when the polysiloxane macro-monomer is a side chain containing a vinyl group, the vinyl group is more likely to react with the active center, but because the vinyl group on the side chain is closer to the polysiloxane segment, it causes poisoning of the active center, greatly reducing the polymerization activity and the polysiloxane insertion rate, and when the polysiloxane macro-monomer is a side chain containing a cyclohexene group, crosslinking occurs during copolymerization, and the compatibilizer is difficult to disperse uniformly during blending, so the compatibilization performance is affected, so among all the synthesized compatibilizers, the compatibilizer 13 is the most preferred compatibilizer, which can retain three types of reaction sites.

[0258] Comparative Examples 13, 15, 16 and 17 can see that the mass fraction of the compatibilizer added is also important, when the mass fraction added is too small, the compatibilization effect is limited, but when the amount of compatibilizer added is too much, the compatibilizer itself is easy to form micelles, and defects are generated in the blend.

[0259] The TEM images of the EPDM / silicone rubber blend rubber chips prepared from Example 13 and Comparative Example 2 can also be observed, and in Example 3 after adding the compatibilizer 3, the phase separation size between the EPDM and the silicone rubber is obviously smaller, indicating that the compatibility between the EPDM and the silicone rubber is increased.

[0260] To further evaluate the aging performance of the EPDM / silicone rubber blend rubber, the vulcanized rubber samples prepared from Examples 3, 13, 15-17 and Comparative Examples 1, 2, 3 were placed in a hot oxygen aging oven, the aging temperature was 125°C, and the aging time was 48h and 72h respectively, the mechanical properties of the samples after aging were tested according to the above method, and the results are shown in Table 4.

[0261] Table 4

[0262]

[0263] The data in Table 4 show that the tensile strength and elongation at break of the blended rubber after aging are better than those of Comparative Examples 1 and 2 by adding only the compatibilizer synthesized in the application without adding any anti-aging auxiliary, the compatibility between the two components of the EPDM / silicone rubber blend without adding the compatibilizer is poor, the silicone rubber is dispersed in the EPDM, the domain size is large, and the distribution is uneven, and the silicone rubber fails to effectively play its protective role. By improving the compatibility, the weather resistance of the silicone rubber can be better utilized.

[0264] The above examples are intended to help understand the method and key points of the application. The content of the specification should not be understood as limiting the application.

Claims

1. A polysiloxane-functionalized polyolefin with multiple reactive sites, characterized in that, The general structural formula is as follows: （Ⅰ）； In the formula: R z Selected from , , , , , One or more of the following; R n Selected from CH3 , , , , One of them; x is selected from natural numbers 1 to 100, y is selected from natural numbers 500 to 2000, z is selected from natural numbers 1 to 100, n is selected from natural numbers 1 to 32, and m is selected from natural numbers 32 to 200.

2. The polysiloxane-functionalized polyolefin with multiple reactive sites according to claim 1, characterized in that, In the polysiloxane-functionalized polyolefin: The molecular weight of the polysiloxane segments is 1.3~19.0 kg / mol; The mass content of the polysiloxane monomer is 1~55%, and the mass content of the third monomer is 0.5~28%. The third monomer is a constituent of R z The monomer of the chain segment is specifically selected from one or more of 1-hexene, propylene, norbornene, 5-ethylidene-2-norbornene, dicyclopentadiene, and 4-vinyl-1-cyclohexene; The weight-average molecular weight is 80~300 kg / mol.

3. A method for preparing a polysiloxane-functionalized polyolefin with multiple reactive sites according to any one of claims 1 to 2, characterized in that, include: (1) Using cyclic forms of hydrogen-containing silanes and siloxanes as raw materials, a double-ended hydrogen-containing polysiloxane macromonomer was prepared by cationic ring-opening polymerization; The cyclic form of the siloxane 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 side-chain functionalized siloxane cyclic forms with the following structural formulas (Ⅱ-1) to (Ⅱ-3); （Ⅱ-1）； （Ⅱ-2）； （Ⅱ-3）； The hydrogen-containing silane is selected from 1,1,3,3-tetramethyldisiloxane; (2) Using vinyl norbornene and the double-ended hydrogen-containing polysiloxane macromonomer prepared in step (1) as raw materials, a hydrosilylation reaction was carried out to obtain a norbornene-based double-ended polysiloxane macromonomer. (3) The norbornene-based double-terminated polysiloxane macromonomer prepared in step (2) is coordinated copolymerized with ethylene and a third monomer to obtain the polysiloxane-functionalized polyolefin with multiple reaction sites.

4. The method for preparing polysiloxane-functionalized polyolefins with multiple reaction sites according to claim 3, characterized in that, In step (1): The molar ratio of the cyclic form of hydrogen-containing silane to siloxane is 1:(8~50); The cationic ring-opening polymerization specifically includes: An acidic catalyst, a siloxane-containing cyclic compound, and a hydrogen-containing silane are uniformly mixed, and cationic ring-opening polymerization is initiated at 0~85℃ to obtain a double-ended hydrogen-containing polysiloxane. The acidic catalyst is selected from one or more of activated clay, trifluoroacetic acid, and concentrated sulfuric acid.

5. The method for preparing polysiloxane-functionalized polyolefins with multiple reaction sites according to claim 3, characterized in that, In step (2): The molar ratio of vinyl norbornene to the dihydrogen-terminated polysiloxane macromonomer is (3~15):1; The hydrosilylation reaction is carried out under the action of a catalyst at a temperature of 50~100℃.

6. The method for preparing polysiloxane-functionalized polyolefins with multiple reaction sites according to claim 3, characterized in that, In step (3), the coordination copolymerization specifically includes: A reaction apparatus equipped with a sealed mechanical stirrer was used to replace the reaction system with an anhydrous and oxygen-free inert ethylene atmosphere. Then, a solvent was added, followed by a co-catalyst, a norbornene-terminated polysiloxane macromonomer, a third monomer, and an activator. Then, a catalyst was added to initiate the polymerization reaction. The ethylene pressure was kept constant throughout the reaction. After the polymerization reaction was completed, the crude product was post-treated to obtain the polysiloxane-functionalized polyolefin. The molar ratio of norbornene-based double-terminated polysiloxane macromonomer to third monomer is 1:(1~100). The initial concentration of norbornene-terminated polysiloxane macromonomer in the reaction system was controlled to be (0.5~20) mmol / L; The pressure within the reaction system is controlled at 0.1~1.0 MPa; The temperature range for coordination copolymerization is 0~70℃.

7. A blend of ethylene propylene diene monomer (EPDM) rubber and silicone rubber, characterized in that, The polysiloxane-functionalized polyolefin with multiple reaction sites as described in any one of claims 1 to 2 is used as a compatibilizer.

8. The EPDM / silicone rubber blend according to claim 7, characterized in that, By weight, the raw material composition includes: 10-90 parts of EPDM rubber; 10-90 parts of silicone rubber; Compatibilizer 0.5-6 parts; 1-3 parts of vulcanizing agent; Vulcanizing aid 1-5 parts.

9. The EPDM / silicone rubber blend according to claim 7, characterized in that, In the polysiloxane-functionalized polyolefin: R z Selected from and / or Or and At least one of them and The combination; R n Selected from CH3 or ; The molecular weight of the polysiloxane segments is 6.1~18.6 kg / mol; the mass content of the polysiloxane monomer is 17~55%.

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