Ionic liquid modified polyethylene and TPO (thermoplastic polyolefin) material as well as preparation method and application thereof

Abstract

The invention discloses a polyethylene and TPO (thermoplastic polyolefin) material modified by ionic liquid as well as a preparation method and application of the polyethylene and TPO material. The polyethylene modified by utilizing the ionic liquid is prepared from raw materials including polyethylene, an initiator and the organic ionic liquid, the TPO material disclosed by the invention is prepared from the following raw materials: PP, polyethylene modified by utilizing ionic liquid, an elastomer, a filler, an antioxidant and a light stabilizer. According to the invention, the organic ion modified polyethylene is firstly prepared by using the ionic liquid, and then the organic ion modified polyethylene is added into the TPO, so that the tensile strength, elongation at break and puncture resistance of TOP can be remarkably improved, and meanwhile, relatively low bending modulus and hardness are maintained; and the low-temperature bending property of the material added with the ionic liquid modified HDPE is not influenced by HDPE crystallization, and the material is free of cracks after being bent at low temperature. Therefore, the TPO material with excellent mechanical properties is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of TPO waterproof coiled materials, and more particularly to polyethylene modified by ionic liquid, TPO materials, and preparation methods and applications thereof. Background Art

[0002] Thermoplastic polyolefin (TPO) waterproofing membrane has excellent comprehensive properties and is a high-performance, environmentally friendly polymer waterproofing membrane that has developed rapidly in recent years. TOP requires strong tensile strength at break, elongation and impact strength to facilitate the requirements for mechanical properties during use. Because the flexibility of TPO waterproofing membrane plays an extremely important role in the construction of the membrane, under the same circumstances, a softer membrane is more conducive to the normal construction. Better flexibility means that it should have appropriate bending modulus and hardness. Too high bending modulus and hardness will lead to reduced flexibility, which is not conducive to installation, construction and application.

[0003] TPO waterproofing membranes contain PP with high crystallinity, so they feel hard and have low flexibility. When more rubber is added, the tensile strength, hardness and flexural strength generally decrease. With the addition of inorganic fillers (such as calcium carbonate), the tensile strength, hardness and flexural modulus will increase accordingly. How to effectively control the relationship between tensile strength, hardness and flexural modulus is a key to developing a new generation of TPO waterproofing membranes. Summary of the invention

[0004] In order to solve the problems in the prior art, the present invention proposes polyethylene and TPO materials modified by ionic liquids, as well as preparation methods and applications thereof. The present invention first uses ionic liquids to prepare organic ion-modified polyethylene, and then adds organic ion-modified polyethylene to TPO, which can significantly increase the tensile strength, elongation at break, and puncture resistance of TOP while maintaining a low bending modulus and hardness; and the low-temperature bendability of the material modified by ionic liquid HDPE is not affected by the crystallization of HDPE, and there is no crack in low-temperature bends. Therefore, the present invention obtains a TPO material with excellent mechanical properties.

[0005] One of the purposes of the present invention is to provide a polyethylene modified by ionic liquid, wherein the polyethylene modified by ionic liquid is prepared from raw materials including polyethylene, an initiator, and an organic ionic liquid; the organic ionic liquid is an organic liquid containing cations and anions;

[0006] By weight percentage, the raw material includes the following components:

[0007] Polyethylene 89-98.9wt%; for example, 89, 90, 91, 92, 93, 94, 95, 96, 87, 98.9wt%;

[0008] Initiator 0.01-2wt%; for example, 0.01, 0.05, 0.1, 0.3, 0.5, 0.7, 0.9, 1, 1.2, 1.5, 1.7, 2wt%;

[0009] Organic ionic liquid 0.1-10wt%; for example, 0.1, 0.5, 1, 3, 5, 7, 8, 9, 10wt%.

[0010] In the polyethylene modified by ionic liquid of the present invention, preferably,

[0011] By weight percentage, the raw material includes the following components:

[0012] Polyethylene 89-95wt%;

[0013] Initiator 0.1-1wt%;

[0014] Organic ionic liquid 5-10wt%.

[0015] In the polyethylene modified by ionic liquid of the present invention, preferably,

[0016] The polyethylene is at least one of metallocene polyethylene, generalized Ziegler-Natta catalytic polymerization polyethylene or high-pressure polyethylene; preferably high-density metallocene polyethylene, medium-density metallocene polyethylene, linear low-density metallocene polyethylene; further preferably, the density range of the polyethylene is: 0.88-0.95 g / cm 3 ; A melt index (MI) in the range of 1-200 g / 10 min, preferably 5-20 g / 10 min; and / or,

[0017] The initiator is selected from at least one of free radical initiators; preferably, the initiator is selected from at least one of dicumyl peroxide, benzoyl peroxide, tert-butyl benzoyl peroxide or methyl ethyl ketone peroxide; and / or,

[0018] The organic ionic liquid is selected from at least one of imidazolium salts, pyridinium salts and pyrazolium salts; preferably, the organic ionic liquid contains phosphorus anions and halogen anions, and more preferably, the organic ionic liquid contains fluorine-containing phosphorus anions.

[0019] In the polyethylene modified by ionic liquid of the present invention, preferably,

[0020] The cation part of the organic ionic liquid contains a long-chain alkyl group of carbon atoms of C8 and above; and / or,

[0021] The cation part of the organic ionic liquid contains a carbon-carbon double bond group. Preferably, the carbon-carbon double bond group is at least one of a vinyl group and a propenyl group.

[0022] Chemical structure of organic ionic liquids:

[0023]

[0024] Any cation can form an ionic liquid with any anion. Preferably, the organic ionic liquid contains imidazolium, pyridinium and / or pyrazolium. The anion portion of the further preferred ionic liquid contains a long-chain alkyl group of 8 or more carbon atoms, and the further preferred ionic liquid contains a phosphorus anion (phosphonium), especially a fluorine-containing phosphorus anion (PF6).

[0025] Further preferred organic ionic liquids contain imidazolium, pyridinium and / or pyrazolium. Imidazolium, pyridinium and pyrazolium contain carbon-carbon double bond groups, such as vinyl, propenyl, or other similar unsaturated groups.

[0026] More preferably, the organic ionic liquid is selected from at least one of 1-22-alkyl 3-methyl imidazolium hexafluorophosphate or 1-vinyl 3-methyl imidazolium chloride.

[0027] The second object of the present invention is to provide a method for preparing polyethylene modified by ionic liquid, comprising the following steps:

[0028] The raw materials including the organic ionic liquid, the initiator and the polyethylene are uniformly mixed and kneaded to obtain the ionic liquid modified polyethylene.

[0029] As a preferred embodiment, after the raw materials including the organic ionic liquid and the initiator are uniformly mixed, polyethylene is added and mixed uniformly, and kneaded to obtain the ionic liquid-modified polyethylene.

[0030] In the technical solution of the present invention, the mixing adopts the existing commonly used mixing conditions. Preferably, the mixing is carried out at 130-140° C. for 2-4 minutes, and then further mixed at 145-190° C. for 1-3 minutes.

[0031] The third object of the present invention is to provide a TPO material, which is made of raw materials including PP, polyethylene modified by ionic liquid, elastomer, filler, antioxidant and light stabilizer;

[0032] The polyethylene modified with ionic liquid is selected from the polyethylene modified with ionic liquid described in one of the purposes of the present invention.

[0033] The TPO material of the present invention is prepared from raw materials including the following components:

[0034] PP (polypropylene) 30-70wt%; for example, 30, 40, 45, 50, 52.7, 55, 60, 65, 70wt%;

[0035] 5-20wt% of polyethylene modified with ionic liquid; for example, 5, 7, 8, 9, 10, 10.5, 12, 15, 17, 19, 20wt%;

[0036] Elastomer 10-30wt%; for example, 10, 15, 20, 25, 30wt%;

[0037] Filler 10-50wt%; for example, 10, 15, 20, 25, 30, 39, 40, 45, 50wt%;

[0038] Antioxidant 0.01-1wt%; for example, 0.01, 0.05, 0.1, 0.3, 0.5, 0.7, 0.9, 1wt%;

[0039] Light stabilizer 0.01-1wt%; for example, 0.01, 0.05, 0.1, 0.3, 0.5, 0.7, 0.9, 1wt%.

[0040] Preferably,

[0041] The TPO material is made from raw materials including the following components:

[0042]

[0043] In the TPO material described in the present invention, preferably,

[0044] The elastomer is selected from at least one of EPDM rubber and polyolefin thermoplastic elastomer (TPO, brand: CA02A, manufacturer: LyondellBasell); and / or,

[0045] The filler is selected from at least one of talc, calcium carbonate or talcum powder; and / or,

[0046] The antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant; preferably, the hindered phenol antioxidant is selected from hindered phenol antioxidant 1010 (Rianlon); the phosphite antioxidant is selected from phosphite antioxidant 168 (Rianlon); further preferably, the mass ratio of the hindered phenol antioxidant to the phosphite antioxidant is 1:1; and / or,

[0047] The light stabilizer is a hindered amine light stabilizer. Preferably, the hindered amine light stabilizer is the hindered amine light stabilizer Chimassorb 944 (Lianglong).

[0048] The fourth object of the present invention is to provide a method for preparing the TPO material described in the third object of the present invention.

[0049] The TPO material is prepared by melt-blending and extruding raw materials including PP, polyethylene modified by ionic liquid, elastomer, filler, antioxidant and light stabilizer.

[0050] In the scheme of the present invention, the blending adopts the existing commonly used melt blending conditions. Preferably, during the melt blending, a twin-screw extruder is used to perform melt extrusion granulation at 180-200° C. and a speed of 180-220 rpm.

[0051] The fifth object of the present invention is to provide a use of the TPO material as described in the fourth object of the present invention in the preparation of TPO waterproof membrane.

[0052] The endpoints and any values ​​of the scope disclosed in the present invention are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, the endpoint values ​​of each scope, the endpoint values ​​of each scope and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in this article. Hereinafter, in principle, each technical solution can be combined with each other to obtain a new technical solution, which should also be regarded as specifically disclosed in this article.

[0053] The beneficial effects of the present invention are:

[0054] By using organic ionic liquid to graft and modify polyethylene, a modified polyethylene with a wide molecular weight distribution is obtained, thereby increasing the dispersion in the TPO system. Moreover, since the organic ionic liquid modified polyethylene has a certain compatibility with both the rubber phase and the inorganic filler, the dispersion of the rubber phase and the inorganic filler in TPO is also improved. This greatly improves the puncture resistance of TPO while maintaining a low bending modulus and hardness; and the low-temperature bendability of the material modified by the ionic liquid HDPE is not affected by the crystallization of HDPE, and there is no crack in the low-temperature bend, thus obtaining a TPO material with excellent mechanical properties. Moreover, due to the addition of the low-melting-temperature organic ionic liquid modified polyethylene, the hot melt welding performance should also be improved. DETAILED DESCRIPTION

[0055] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0056] It should also be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0057] In addition, the various embodiments of the present invention may be arbitrarily combined as long as they do not violate the concept of the present invention. The technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0058] The raw materials used in the examples and comparative examples, unless otherwise specified, are disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0059] Example 1

[0060] Preparation of 1-22-alkyl 3-methyl imidazolium hexafluorophosphate:

[0061] 20 g of 1-methylimidazole (Sigma-Aldrich) and 107 g of 1-bromodocosane (Sigma-Aldrich) were dissolved in 200 ml of acetonitrile (Sigma-Aldrich). The mixture was refluxed at 85°C for 24 hours and then cooled to room temperature. The resulting product was filtered and washed three times with ether. It was then dried in a vacuum oven to obtain 1-docosanyl-3-methylimidazolium bromide. The yield of the process was about 80%, and the melting point of the resulting product was about 83°C.

[0062] About 20g of 1-di-di-1 ...

[0063] Preparation of ionic liquid modified HDPE:

[0064] High-density polyethylene (HDPE) (ExxonMobil TM HDPE HD 6706, density: 0.952g / cm 3 , MI, 6.7g / 10min) 92.90wt%;

[0065] Initiator (dicumyl peroxide) 0.10wt%;

[0066] Organic ionic liquid (1-22 alkyl 3-methyl imidazolium hexafluorophosphate) 7.00 wt%;

[0067] The organic ionic liquid (1-22-alkyl 3-methyl imidazolium hexafluorophosphate) is mixed evenly with the initiator (appropriate heating is applied to increase the fluidity of the ionic liquid), and then mixed evenly with polyethylene (HDPE) particles. The mixture is added to an internal mixer, mixed at 135°C for 3 minutes, and then further mixed at 150°C for 2 minutes; ~2 kg of ionic liquid-modified HDPE-1 (MI, ~1 g / 10 min) is obtained.

[0068] Preparation of TPO samples:

[0069]

[0070] The above formula was mixed evenly, and melt-extruded and granulated using a twin-screw extruder at 190° C. and 200 rpm to obtain 2 kg of TPO sample 1.

[0071] Example 2

[0072] The ionic liquid modified HDPE is the same as in Example 1, except that more ionic liquid modified HDPE 1 is added to the TPO sample. The formula is shown in Table 1, Example 2. 2 kg of TPO sample 2 is obtained.

[0073] Example 3

[0074] Preparation of ionic liquid modified HDPE

[0075] HDPE:(ExxonMobil TM HDPE HD 6706, density: 0.952g / cm 3 , MI, 6.7g / 10min)

[0076] 95.90wt%;

[0077] Initiator (dicumyl peroxide) 0.1wt%

[0078] Organic ionic liquid (1-vinyl 3-methylimidazolium chloride) 4.0 wt%;

[0079] The organic ionic liquid (1-vinyl 3-methylimidazolium chloride) is mixed evenly with the initiator (appropriate heating is applied to increase the fluidity of the ionic liquid), and then mixed evenly with polyethylene particles (HDPE). The mixture is added to an internal mixer, mixed at 135°C for 3 minutes, and then further mixed at 180°C for 1 minute; ~2 kg of ionic liquid-modified HDPE2 (MI, less than 1 g / 10 min) is obtained.

[0080] Preparation method of TPO:

[0081] Same as Example 1, the formula is shown in Table 1, Example 3.

[0082] Example 4

[0083] The preparation of ionic liquid modified HDPE1 is the same as that in Example 1.

[0084] Preparation of TPO: Use a twin-screw extruder at 190°C and 200 rpm to further mix PP9302, TPO CA02A, ionic liquid modified HDPE1 (content refer to Example 4 in Table 1) antioxidant (Irganox1010, BASF) and Chimassorb944 light stabilizer to obtain the TPO sample (2 kg) of Example 4 of the present invention.

[0085] Example 5

[0086] The preparation of ionic liquid modified HDPE2 is the same as that in Example 3.

[0087] Preparation of TPO: PP9302, CA02A, ionic liquid modified HDPE1 (content refer to Example 5 in Table 1) antioxidant (Irganox 1010, BASF) and Chimassorb 944 light stabilizer were further mixed using a twin-screw extruder at 190°C at a speed of 200 rpm to obtain the TPO sample (2 kg) of Example 5 of the present invention.

[0088] Comparative Example 1

[0089] Using a twin-screw extruder at 190° C. and a speed of 200 rpm, PP9302, EPDM, HDPE (the contents are shown in Table 1 for Comparative Example 1, Comparative Example 2, and Comparative Example 5), an antioxidant (Irganox 1010, BASF), and Chimassorb 944 light stabilizer were further mixed to obtain TPO samples (2 kg each) of Comparative Example 1, Comparative Example 2, and Comparative Example 5 of the present invention.

[0090] Comparative Example 2

[0091] The same preparation method as that of Comparative Example 1 is adopted, and the specific raw materials (contents refer to Comparative Example 2 in Table 1) are

[0092] Comparative Example 3

[0093] Preparation of modified HDPE

[0094] HDPE:(ExxonMobil TM HDPE HD 6706, density: 0.952g / cm 3 , MI, 6.7g / 10min)

[0095] 99.90wt%;

[0096] Initiator (dicumyl peroxide) 0.1wt%

[0097] The initiator and polyethylene (HDPE) particles were mixed uniformly, and the mixture was added to an internal mixer, mixed at 135° C. for 3 min, and then further mixed at 180° C. for 1 min; ~2 kg of modified HDPE was obtained.

[0098] Preparation method of TPO

[0099] Same as Comparative Example 1, the formula is shown in Table 1, Comparative Example 3.

[0100] Comparative Example 4

[0101] The preparation of modified HDPE is the same as that of Comparative Example 3.

[0102] Preparation method of TPO

[0103] The modified HDPE (6.51 wt%) and 0.49 wt% of ionic liquid (1-22 alkyl 3-methyl imidazolium hexafluorophosphate) were added as in Comparative Example 3. Other components are shown in Table 1, Comparative Example 4.

[0104] Comparative Example 5

[0105] The same preparation method as that of Comparative Example 1 is adopted, and the specific content of each raw material is shown in Table 1, Comparative Example 5.

[0106] Comparative Example 6

[0107] The preparation of modified HDPE is the same as that of Comparative Example 3.

[0108] Preparation method of TPO

[0109] The modified HDPE (6.51 wt%) and 0.49 wt% of ionic liquid (1-22 alkyl 3-methyl imidazolium hexafluorophosphate) were added as in Comparative Example 3. Other components are shown in Table 1, Comparative Example 6.

[0110] Table 1

[0111]

[0112] From the results in Table 1, we can see that

[0113] Compared with Comparative Example 1, Example 2 with Comparative Example 2, and Example 4 with Comparative Example 5, it can be seen that the puncture resistance and low-temperature bendability of the TPO material prepared from unmodified pure HDPE in Comparative Example 1, Comparative Example 2 or Comparative Example 5 are significantly worse than those of the TPO material prepared from modified HDPE in Example 1 or Example 3, Example 2, Example 4 or Example 5; in addition, the TPO material prepared in the above embodiments of the present invention maintains a lower flexural modulus and hardness at the same time, and has better comprehensive performance.

[0114] Compared with Comparative Example 3, Example 4 or Example 5 of the present invention, it can be seen that the puncture resistance and low-temperature bendability of the TPO material prepared by HDPE without ionic liquid modification in Comparative Example 3 or Comparative Example 6 are significantly worse than those of the TPO material prepared by HDPE modified with ionic liquid in Example 1 or Example 3; in addition, the TPO material prepared by the above embodiments of the present invention maintains a lower bending modulus and hardness at the same time, and has better comprehensive performance.

[0115] Compared with Comparative Example 4, Example 1 or Example 3 of the present invention shows that the puncture resistance and low-temperature bendability of the TPO material prepared in Comparative Example 4 using a mixture of HDPE+ionic liquid not modified with ionic liquid are significantly worse than those of the TPO material prepared in Example 1 or Example 3 using modified HDPE modified with ionic liquid; in addition, the TPO material prepared in the above-mentioned embodiments of the present invention maintains a lower flexural modulus and hardness at the same time, and has better comprehensive performance.

[0116] In addition, compared with Comparative Examples 1, 3 and 4, it is found that the tensile strength and elongation at break of the TPO material prepared by the present invention are also significantly improved in Example 1 of the present invention; for example, the tensile strength of Example 1 of the present invention [250 mm / min] is 8.95 MPa, and the elongation at break [250 mm / min] is 528%; while the tensile strength of Comparative Example 1 is 7.84 MPa, and the elongation at break [250 mm / min] is 458%; the tensile strength of Comparative Example 3 is 7.91 MPa, and the elongation at break [250 mm / min] is 482%; the tensile strength of Comparative Example 4 is 7.71 MPa, and the elongation at break [250 mm / min] is 490%.

[0117] In summary, the addition of ionic liquid to modify HDPE in the present invention can significantly increase the tensile strength, elongation at break, and puncture resistance of TOP, while maintaining a low bending modulus and hardness; and the low-temperature bendability of the material modified by ionic liquid to HDPE is not affected by the crystallization of HDPE, and there is no crack in the low-temperature bend. This may be due to the fact that in the HDPE modified by ionic liquid, not only there is a grafting reaction between the HDPE molecular chains to form long chain branches (long chain branches) to increase the distribution of molecular weight, which is beneficial to the dispersion in TPO, but also part of the ionic liquid is grafted on the HDPE molecular chain to become a good compatibilizer, which increases the compatibility with talcum powder and elastomer parts, which is beneficial to the dispersion of talcum powder and elastomer. At the same time, the small molecule ionic liquid also has a lubricating effect, thereby reducing and offsetting the performance impact caused by the improvement of crystallization performance caused by the addition of modified HDPE. In the comparative examples, whether HDPE (Comparative Examples 1, 2, 5), modified HDPE (Comparative Examples 3, 6), or modified HDPE and ionic liquid (Comparative Example 4) is added alone, the above effects cannot be achieved.

[0118] Moreover, due to the addition of low melting temperature organic ionic liquid modified polyethylene, the hot melt welding performance of the TPO material of the present invention is also improved.

[0119] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0120] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0121] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0122] In the context of the present specification, any matters or items not mentioned are directly applicable to those known in the art without any changes except those explicitly stated.

Claims

1. A polyethylene modified by ionic liquid, characterized in that: The polyethylene modified by ionic liquid is prepared from raw materials including polyethylene, initiator, and organic ionic liquid; the organic ionic liquid is an organic liquid containing cations and anions; By weight percentage, the raw material includes the following components: Polyethylene 89-98.9wt%; Initiator 0.01-2wt%; Organic ionic liquid 0.1-10wt%.

2. The polyethylene modified by ionic liquid according to claim 1, characterized in that: By weight percentage, the raw material includes the following components: Polyethylene 89-95wt%; Initiator 0.1-1wt%; Organic ionic liquid 5-10wt%.

3. The polyethylene modified by ionic liquid according to claim 1, characterized in that: The polyethylene is at least one of metallocene polyethylene, generalized Ziegler-Natta catalytic polymerization polyethylene or high-pressure polyethylene; preferably high-density metallocene polyethylene, medium-density metallocene polyethylene, linear low-density metallocene polyethylene; further preferably, the density of the polyethylene is in the range of 0.88-0.95 g / cm 3 ; The melt index range is 1-200g / 10min, preferably 5-20g / 10min; and / or, The initiator is selected from at least one of free radical initiators; preferably, the initiator is selected from at least one of dicumyl peroxide, benzoyl peroxide, tert-butyl benzoyl peroxide or methyl ethyl ketone peroxide; and / or, The organic ionic liquid is selected from at least one of imidazolium salts, pyridinium salts and pyrazolium salts; preferably, the organic ionic liquid contains phosphorus anions and halogen anions, and more preferably, the organic ionic liquid contains fluorine-containing phosphorus anions.

4. The polyethylene modified by ionic liquid according to claim 3, characterized in that: The cation part of the organic ionic liquid contains a long-chain alkyl group of carbon atoms of C8 and above; and / or, The cation part of the organic ionic liquid contains a carbon-carbon double bond group. Preferably, the carbon-carbon double bond group is at least one of a vinyl group and a propenyl group.

5. The method for preparing polyethylene modified by ionic liquid according to any one of claims 1 to 4, characterized in that: The following steps are involved: The raw materials including the organic ionic liquid, the initiator and the polyethylene are uniformly mixed and kneaded to obtain the ionic liquid modified polyethylene.

6. A TPO material, characterized in that: Made of raw materials including PP, polyethylene modified with ionic liquid, elastomer, filler, antioxidant and light stabilizer; The polyethylene modified with ionic liquid is selected from the polyethylene modified with ionic liquid according to any one of claims 1 to 4.

7. The TPO material according to claim 6, characterized in that: The TPO material is made from raw materials including the following components: Preferably, 8. The TPO material according to claim 6, characterized in that: The elastomer is selected from at least one of EPDM rubber and polyolefin thermoplastic elastomer; and / or, The filler is selected from at least one of talc, calcium carbonate or talcum powder; and / or, The antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant; preferably, the hindered phenol antioxidant is selected from hindered phenol antioxidant 1010; the phosphite antioxidant is selected from phosphite antioxidant 168; further preferably, the mass ratio of the hindered phenol antioxidant to the phosphite antioxidant is 1:1; and / or, The light stabilizer is a hindered amine light stabilizer.

9. The method for preparing the TPO material according to any one of claims 6 to 8, characterized in that: The TPO material is prepared by melt-blending and extruding raw materials including PP, polyethylene modified by ionic liquid, elastomer, filler, antioxidant and light stabilizer.

10. Use of the TPO material according to any one of claims 6 to 8 in preparing TPO waterproofing membrane.

Images