Ion-modified polypropylene resin composition with wide molecular weight distribution and preparation method thereof

Abstract

The invention belongs to the technical field of high polymer materials, and discloses an ion-modified polypropylene resin composition with wide molecular weight distribution and a preparation method thereof, the resin composition contains polypropylene with wide molecular weight distribution, organic acid / anhydride, organic metal salt and a functional auxiliary agent; based on 100 parts by weight of the polypropylene with wide molecular weight distribution, the content of the organic acid / acid anhydride is 0.1-3 parts by weight, the content of the organic metal salt is 0.1-2 parts by weight, and the content of the functional additive is 0.01-1 part by weight. According to the ion-modified polypropylene resin composition with wide molecular weight distribution, the melt strength is improved while the viscosity is reduced, and the application of the ion-modified polypropylene resin composition in high resin sag resistance processing technologies such as foaming, film blowing and hollowing is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to an ion-modified molecular weight wide distribution polypropylene resin composition and a preparation method thereof. Background Art

[0002] Due to the difference in molecular structure, the difference in melt rheological properties of polymers under different temperature fields and different processing flow fields has a great impact on process conditions and product quality. Common rheological property tests for polymers include using rotational rheology to characterize the changes in polymer apparent viscosity η* and shear modulus (G' storage modulus and G" loss modulus) under shear flow field; using extensional rheology to examine whether polymers will undergo tensile strain hardening under extensional flow field; and using melt strength tests to evaluate the ability of polymer melts to resist sag at different temperatures.

[0003] The most common way to improve the viscoelasticity and anti-sag of PP is to increase the molecular weight of PP. However, excessively large molecular weight segments will form serious entanglements in the melt, thereby hindering the movement of the molecular chain and increasing the difficulty of PP processing. In order to solve this problem, on the one hand, the molecular weight and distribution of PP can be adjusted by controlling the catalyst system and polymerization process to obtain wide molecular weight distribution PP (BMWDPP). Large molecular weight segments improve the viscoelasticity of PP, and small molecular weight segments improve the processability of PP; on the other hand, long-chain branched PP (LCPP) can be processed through the polymerization process or reaction. The introduction of long chain branches can bring about tensile hardening and improve the melt strength of the resin.

[0004] BMWDPP is easier to prepare directly by polymerization than LCPP, but due to the presence of internal linear high molecular weight segments, its viscoelasticity is higher than that of LCPP, and its zero shear viscosity at 210°C is usually around 10 5 Pa·s order of magnitude, anti-sag is more sensitive to temperature changes, and processing performance is slightly inferior; LCPP polymerization preparation and reaction processing are difficult, the formation of long-chain branched structures is highly random, and it is not easy to stably regulate, and the long-chain branched structure easily leads to an increase in the apparent viscosity η* and η0 of the resin, increasing processing energy consumption and difficulty. If BMWDPP can be modified in some way so that it can significantly reduce the apparent viscosity while also undergoing tensile hardening caused by non-long-chain branches to increase its melt strength, it is expected to improve its viscoelasticity and processing performance, so as to better carry out applications in high value-added processing technologies such as foaming, hollow molding, and film blowing. Summary of the invention

[0005] In view of the above problems existing in the prior art, the object of the present invention is to provide an ion-modified polypropylene resin composition with a wide molecular weight distribution and a preparation method thereof, which can improve the processing ability of the resin while also improving its melt strength, thereby improving the viscoelasticity and processing performance of the resin at the same time, so that it can be better applied in high value-added processing technologies such as foaming, hollow molding, and film blowing.

[0006] The first aspect of the present invention provides an ion-modified molecular weight broad distribution polypropylene resin composition, the resin composition comprising molecular weight broad distribution polypropylene, organic acid / acid anhydride, organic metal salt and functional additive;

[0007] Based on 100 parts by weight of the molecular weight broad distribution polypropylene, the content of the organic acid / anhydride is 0.1 to 3 parts by weight, the content of the organic metal salt is 0.1 to 2 parts by weight, and the content of the functional additive is 0.01 to 1 part by weight.

[0008] The second aspect of the present invention provides a method for preparing the above-mentioned ion-modified molecular weight broad distribution polypropylene resin composition, the preparation method comprising:

[0009] 1) mixing the broad molecular weight distribution polypropylene, the organic acid / acid anhydride and the organic metal salt, and extruding and granulating the mixture to obtain composite particles;

[0010] 2) After mixing the composition particles with the functional additives, extrusion granulation is performed to obtain the ion-modified molecular weight wide distribution polypropylene resin composition.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The ion-modified molecular weight wide distribution polypropylene resin composition of the present invention has the tensile hardening phenomenon through ion modification while maintaining the characteristics of molecular weight wide distribution;

[0013] 2. The η0 of the ion-modified molecular weight wide distribution polypropylene resin composition of the present invention is greatly reduced, thereby improving its flowability and processing performance;

[0014] 3. The ion-modified molecular weight broad distribution polypropylene resin composition of the present invention has a lower viscosity and an increased melt strength, which is beneficial to its application in high processing technologies requiring high sag resistance of the resin, such as foaming, film blowing and hollow molding.

[0015] 4. The preparation process of the ion-modified molecular weight wide distribution polypropylene resin composition of the present invention is simple and is conducive to promotion.

[0016] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 η* comparison curve of the polypropylene resin composition obtained in Example 1 and Comparative Example 1.

[0018] Figure 2 G' and G" curves of the polypropylene resin compositions obtained in Example 1 and Comparative Example 1, from which η0 can be calculated.

[0019] Figure 3 This is the tensile strain curve of the polypropylene resin composition obtained in Example 1.

[0020] Figure 4 This is the tensile strain curve of the polypropylene resin composition obtained in Comparative Example 1.

[0021] Figure 5 The melt strength curves of the polypropylene resin compositions obtained in Example 1 and Comparative Example 1 are shown. DETAILED DESCRIPTION

[0022] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0023] According to a first aspect of the present invention, the present invention provides an ion-modified molecular weight broad distribution polypropylene resin composition, the resin composition comprising molecular weight broad distribution polypropylene, organic acid / acid anhydride, organic metal salt and functional additive;

[0024] Based on 100 parts by weight of the molecular weight broad distribution polypropylene, the content of the organic acid / anhydride is 0.1 to 3 parts by weight, the content of the organic metal salt is 0.1 to 2 parts by weight, and the content of the functional additive is 0.01 to 1 part by weight.

[0025] In the present invention, the molecular weight broad distribution polypropylene raw material can be polypropylene with a molecular weight distribution ≥ 8, and the molecular weight distribution (PDI) is usually obtained by gel permeation chromatography (GPC) testing.

[0026] According to the present invention, the molecular weight wide distribution polypropylene can be selected from at least one of homopolymerized polypropylene (such as homopolymerized molecular weight wide distribution polypropylene HMS20Z produced by Sinopec Zhenhai Refining and Chemical), ethylene-propylene random copolymerized polypropylene (such as ethylene-propylene random copolymerized polypropylene E02ES), propylene-butyl random copolymerized polypropylene, ternary random copolymerized polypropylene and impact copolymerized polypropylene. The molecular weight wide distribution polypropylene can be prepared by melt blending, mixed catalyst method, multi-active center catalytic polymerization method, step-by-step polymerization method or multi-zone circulation reactor method. The specific process is known to those skilled in the art and will not be repeated here.

[0027] The present invention adds a certain amount of organic acid / anhydride and organic metal salt to directly polymerized wide molecular weight distribution polypropylene, and forms a "quasi-long chain branch" structure in the polypropylene through the mutual agglomeration effect of particle cluster groups grafted on the polypropylene molecular chain, which can bring about a stretching hardening effect and reduce the shear viscosity of the resin.

[0028] In the present invention, the organic acid / anhydride can be selected from at least one of maleic acid, maleic anhydride, citric acid, methacrylic acid, acrylic acid, phthalic acid, phthalic anhydride, terephthalic acid, terephthalic anhydride, isophthalic acid and isophthalic anhydride.

[0029] According to the present invention, the organic metal salt is a metal salt with an acetyl group. Preferably, the organic metal salt is at least one selected from zinc acetylacetonate, aluminum acetylacetonate, copper acetylacetonate, cobalt acetylacetonate and nickel acetylacetonate.

[0030] In the present invention, the functional additive can be various functional additives commonly used in the art, for example, it can be selected from at least one of antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, metal deactivators, pigments, nucleating agents, foam control agents, fillers, stabilizers, reinforcing agents and lubricants.

[0031] According to the present invention, the antioxidant may be any antioxidant conventionally used in the art. Preferably, the antioxidant is a hindered phenol antioxidant and a phosphite antioxidant mixed in a mass ratio of 1-5:5-1. The hindered phenol antioxidant may be selected from antioxidant 1010, antioxidant 1076, antioxidant 245 or antioxidant 246; the phosphite antioxidant may be selected from triphenyl phosphate, trimethyl phosphate or antioxidant 168.

[0032] Preferably, based on 100 parts by weight of the molecular weight broad distribution polypropylene, the content of the organic acid / anhydride is 0.5-1.5 parts by weight, the content of the organic metal salt is 0.3-1 part by weight, and the content of the functional additive is 0.03-0.5 part by weight.

[0033] The PDI of the ion-modified broad molecular weight distribution polypropylene resin composition of the present invention is ≥8.0, preferably ≥9.0, and η0≤8.0×10 4 Pa·s, preferably ≤5.5×10 4 Pa·s, melt strength ≥0.20N, preferably ≥0.22N; compared with the unmodified molecular weight broad distribution polypropylene, the η0 of the ion-modified molecular weight broad distribution polypropylene resin composition is reduced by 60%, preferably by 75%, η0 is η0 at 210°C, the melt strength is increased by 15%, preferably by 30%, tensile hardening occurs, and the melt strength is the melt strength measured at 210°C according to the method provided by the present invention.

[0034] According to a second aspect of the present invention, the present invention provides a method for preparing the above-mentioned ion-modified molecular weight broad distribution polypropylene resin composition, the preparation method comprising:

[0035] 1) mixing the broad molecular weight distribution polypropylene, the organic acid / acid anhydride and the organic metal salt, and extruding and granulating the mixture to obtain composite particles;

[0036] 2) After mixing the composition particles with the functional additives, extrusion granulation is performed to obtain the ion-modified molecular weight wide distribution polypropylene resin composition.

[0037] In the present invention, the mixing of materials can be carried out by various mixing equipment used in the prior art, such as a high-speed mixer, a kneader, etc. Extrusion granulation can be carried out in an extrusion molding machine, through one or more die heads of a twin-screw or single-screw extruder to extrude into wires and cut to obtain, and the die head temperature can be selected as required. These are all conventional options that can be made by those skilled in the art with reference to the prior art, and will not be described in detail here.

[0038] The substances and parameters not limited in the present invention can be selected according to the existing technology and belong to the conventional technical means in this field.

[0039] The present invention will be further described below with reference to the following examples, but is not limited to these examples.

[0040] In the following examples and comparative examples, the raw materials and instruments used include:

[0041] Homopolymer polypropylene with broad molecular weight distribution HMS20Z: Sinopec Zhenhai Refining & Chemical Co., Ltd.

[0042] Ethylene-propylene copolymer polypropylene with broad molecular weight distribution E02ES: Sinopec Zhenhai Refining and Chemical.

[0043] General homopolymer polypropylene T03: Sinopec Zhenhai Refining and Chemical.

[0044] Maleic anhydride: J&K, analytical grade.

[0045] Acrylic acid: J&K, analytical grade.

[0046] Zinc acetylacetonate: J&K, analytical grade.

[0047] Aluminum acetylacetonate: J&K, analytical grade.

[0048] 2,5-Dimethyl-2,5-bis(tert-butylperoxy)hexane (DMDBH): J&K, analytical grade.

[0049] Pentaerythritol (PETA): J&K, analytical grade.

[0050] Antioxidant 1010: BASF.

[0051] Antioxidant 168: BASF.

[0052] Twin-screw extruder ZE26: Krauss-Maffei, Germany.

[0053] Strand pelletizer PRIMO 60E: Magg, Germany.

[0054] Rotational rheometer MCR302: Anton Paar, Austria.

[0055] ARES-G2 extensional rheometer: TA Company, USA.

[0056] GPC gel chromatograph Waters-208: Waters Company, USA.

[0057] Melt extensional rheometer RHEOTENS 71.97: Gottfert, Germany.

[0058] In the following examples and comparative examples, the testing methods of the relevant data are as follows:

[0059] 1. Polypropylene resin composition η*: At 210°C, the shear rate range is 0.01-100 rad / s, the strain value is 5%, and the relationship curve between the apparent viscosity η* and the shear rate w is measured by a rotational rheometer. Usually, the value when η* in the low-frequency region no longer increases with the shear rate can be read as η0 of the polyolefin resin composition. However, since the η* of polypropylene with a wide molecular weight distribution is very high, η0 cannot be read within the conventional test range.

[0060] 2. Polypropylene resin composition η0: The viscosity of the fluid measured when the shear rate tends to zero is called zero shear viscosity (η0), which is closely related to the test temperature, molecular weight and molecular weight distribution.

[0061] The different molecular weight distributions of polypropylene result in the intersection of the storage modulus (G') and the loss modulus (G") at different frequencies. The modulus (G x =G'=G") is used to define the rheological polydispersity index PI. That is, the formula:

[0062] PI=10 5 / G x

[0063] The zero shear viscosity of polypropylene at a certain temperature can also be expressed as G x The corresponding shear frequency ω x And PI is calculated. That is, the formula:

[0064] ln(η0ω x)=14.73-0.237lnPI

[0065] 3. PDI of polypropylene resin composition: The relative molecular mass and its distribution of the sample are tested by gel permeation chromatography (GPC). The solvent and mobile phase are both 1,2,4-trichlorobenzene (containing 0.025% antioxidant 2,6-dibutyl-p-cresol), the column temperature is set to 150°C, the flow rate is set to 1.0mL / min, and a narrow distribution polystyrene standard is used for universal calibration. The weight average molecular weight Mw and number average molecular weight Mn of the sample are measured, and the molecular distribution index (PDI) is the value obtained by Mw / Mn.

[0066] 4. Tensile strain of polypropylene resin composition: The test temperature is set to 150°C and the stretching rate is 0.01 to 3s -1 , the tensile strain value is 3. Observe whether tensile hardening occurs.

[0067] 5. Melt strength of polypropylene resin composition: The stretching roller spacing of the melt extension rheometer was set to 4 mm, the distance between the vertical extrusion die and the center of the stretching roller was 60 mm, the screw speed was 5 r / min, and the stretching roller rotation acceleration was 20 m / s 2 The tensile force measured when the melt strand breaks is recorded as the melt strength, and the relative stretching speed (speed at break / initial stretching speed) is the draw ratio. Repeat the test for 5 times and take the average value, and test at 210°C at the extrusion die.

[0068] Example 1

[0069] 100 parts by weight of HMS20Z, 1.2 parts by weight of maleic anhydride and 0.6 parts by weight of zinc acetylacetonate were added to a twin-screw extruder in different weight loss scales, extruded into strands and pelletized at a die head temperature of 210°C to obtain composite particles. The composite particles were then blended evenly with an antioxidant (based on 100 parts by weight of HMS20Z in the composite particles, 0.2 parts by weight of antioxidant 1010 and 0.1 parts by weight of antioxidant 168) in a high-speed mixer, added to a twin-screw extruder, extruded into strands and pelletized at a die head temperature of 210°C, and dried to obtain an ion-modified polypropylene resin composition with a wide molecular weight distribution. The η0, PDI, tensile strain results and melt strength are shown in Table 1 and Figure 1 , 2 , 3, 5.

[0070] Example 2

[0071] Same as Example 1, except that zinc acetylacetonate is replaced by aluminum acetylacetonate. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified broad molecular weight distribution polypropylene resin composition are shown in Table 1.

[0072] Example 3

[0073] Same as Example 1, except that maleic anhydride is replaced by acrylic acid. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified broad molecular weight distribution polypropylene resin composition are shown in Table 1.

[0074] Example 4

[0075] Same as Example 1, except that the amount of maleic anhydride was changed from 1.2 parts by weight to 1.8 parts by weight, and the amount of zinc acetylacetonate was changed from 0.6 parts by weight to 0.9 parts by weight. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified molecular weight broad distribution polypropylene resin composition are shown in Table 1.

[0076] Example 5

[0077] Same as Example 1, except that the amount of maleic anhydride is changed from 1.2 parts by weight to 0.6 parts by weight, and the amount of zinc acetylacetonate is changed from 0.6 parts by weight to 0.3 parts by weight. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified molecular weight wide distribution polypropylene resin composition are shown in Table 1.

[0078] Example 6

[0079] Same as Example 1, except that the amount of maleic anhydride is changed from 1.2 parts by weight to 0.2 parts by weight, and the amount of zinc acetylacetonate is changed from 0.6 parts by weight to 1.6 parts by weight. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified molecular weight wide distribution polypropylene resin composition are shown in Table 1.

[0080] Example 7

[0081] Same as Example 1, except that the amount of maleic anhydride is changed from 1.2 parts by weight to 1.65 parts by weight, and the amount of zinc acetylacetonate is changed from 0.6 parts by weight to 0.15 parts by weight. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified molecular weight broad distribution polypropylene resin composition are shown in Table 1.

[0082] Example 8

[0083] Same as Example 1, except that HMS20Z is replaced with E02ES. The η0, PDI, tensile strain results and melt strength of the obtained ion-modified broad molecular weight distribution polypropylene resin composition are shown in Table 1.

[0084] Comparative Example 1

[0085] 100 parts by weight of HMS20Z, 0.2 parts by weight of antioxidant 1010 and 0.1 parts by weight of antioxidant 168 were mixed evenly in a high-speed mixer, and then added to a twin-screw extruder. The die head temperature was 210°C and the strands were extruded and pelletized. The polypropylene resin composition was obtained by drying. Its η0, PDI, tensile strain results and melt strength are shown in Table 1 and Figure 1 , 2 , 4, 5.

[0086] Comparative Example 2

[0087] The same as comparative example 1, except that HMS20Z is replaced with E02ES. The η0, PDI, tensile strain results and melt strength of the obtained polypropylene resin composition are shown in Table 1.

[0088] Comparative Example 3

[0089] Same as Example 1, except that 1.2 parts by weight of maleic anhydride was replaced by 0.1 parts by weight of peroxide DMDB, and 0.6 parts by weight of zinc acetylacetonate was replaced by 2.0 parts by weight of PETA. A long-chain branched modified molecular weight broad distribution polypropylene resin composition was obtained, and its η0, PDI, tensile strain results and melt strength are shown in Table 1.

[0090] Comparative Example 4

[0091] The same as comparative example 3, except that PETA was not added. A polypropylene resin composition with a wide molecular weight distribution was obtained, and its η0, PDI, tensile strain results and melt strength are shown in Table 1.

[0092] Comparative Example 5

[0093] Same as Example 1, except that the amount of maleic anhydride was changed from 1.2 parts by weight to 0.08 parts by weight, and the amount of zinc acetylacetonate was changed from 0.6 parts by weight to 0.08 parts by weight. The η0, PDI, tensile strain results and melt strength of the obtained polypropylene resin composition are shown in Table 1.

[0094] Comparative Example 6

[0095] The same as Example 1, except that the amount of maleic anhydride was changed from 1.2 parts by weight to 3.3 parts by weight, and the amount of zinc acetylacetonate was changed from 0.6 parts by weight to 2.2 parts by weight.

[0096] Comparative Example 7

[0097] The same as comparative example 1, except that HMS20Z is replaced with T03. The η0, PDI, tensile strain results and melt strength of the obtained polypropylene resin composition are shown in Table 1.

[0098] Comparative Example 8

[0099] Same as Example 1, except that HMS20Z is replaced with T03. The η0, PDI, tensile strain results and melt strength of the obtained polypropylene resin composition are shown in Table 1.

[0100] Table 1

[0101]

[0102]

[0103] From the results of Examples 1-3, 8 and Comparative Examples 1 and 2 in Table 1, it can be seen that different types of organic acids / anhydrides and organic metal salts can play an ion-modifying role on the homopolymer or copolymer wide molecular weight distribution polypropylene, significantly reducing η0 of the resin composition while causing tensile hardening and improving the melt strength under the same test conditions.

[0104] From Examples 4-7 and Comparative Examples 5-6, it can be seen that by changing the addition amount and ratio of organic acid / anhydride and organic metal salt within a certain range, the broad molecular weight distribution polypropylene can still significantly reduce the η0 of the resin composition, while tensile hardening occurs and the melt strength is improved under the same test conditions. However, beyond the scope of the present invention, too low an addition amount cannot reduce η0, and too high an addition amount leads to reduced melt strength.

[0105] As can be seen from Comparative Example 3, although long-chain branched molecular weight broad distribution polypropylene can produce tensile hardening and improve melt strength, η0 will also increase. As can be seen from Comparative Example 4, although degraded molecular weight broad distribution polypropylene can reduce η0, tensile hardening will not occur and the melt strength will also be significantly reduced.

[0106] From the results of Comparative Examples 7 and 8, it can be seen that ion modification using linear polypropylene as raw material will also produce tensile hardening phenomenon, but η0 will increase, and although the melt strength is improved, it is still relatively low.

[0107] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. An ion-modified molecular weight broad distribution polypropylene resin composition, characterized in that: The resin composition contains polypropylene with wide molecular weight distribution, organic acid / acid anhydride, organic metal salt and functional additive; Based on 100 parts by weight of the molecular weight broad distribution polypropylene, the content of the organic acid / anhydride is 0.1 to 3 parts by weight, the content of the organic metal salt is 0.1 to 2 parts by weight, and the content of the functional additive is 0.01 to 1 part by weight.

2. The ion-modified molecular weight broad distribution polypropylene resin composition according to claim 1, wherein The molecular weight distribution of the broad molecular weight distribution polypropylene is ≥8.

3. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 1 or 2, wherein: The molecular weight wide distribution polypropylene is selected from at least one of homopolymer polypropylene, ethylene-propylene random copolymer polypropylene, propylene-butylene random copolymer polypropylene, terpolymer random copolymer polypropylene and impact copolymer polypropylene.

4. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 1, wherein: The organic acid / anhydride is selected from at least one of maleic acid, maleic anhydride, citric acid, methacrylic acid, acrylic acid, phthalic acid, phthalic anhydride, terephthalic acid, terephthalic anhydride, isophthalic acid and isophthalic anhydride.

5. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 1, wherein: The organic metal salt is a metal salt with an acetyl group; Preferably, the organic metal salt is selected from at least one of zinc acetylacetonate, aluminum acetylacetonate, copper acetylacetonate, cobalt acetylacetonate and nickel acetylacetonate.

6. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 1, wherein: The functional additive is selected from at least one of antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, metal deactivators, pigments, nucleating agents, foam control agents, fillers, stabilizers, reinforcing agents and lubricants.

7. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 6, wherein: The antioxidant is a hindered phenol antioxidant and a phosphite antioxidant mixed in a mass ratio of 1-5:5-1; wherein the hindered phenol antioxidant is selected from antioxidant 1010, antioxidant 1076, antioxidant 245 or antioxidant 246; and the phosphite antioxidant is selected from triphenyl phosphate, trimethyl phosphate or antioxidant 168.

8. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 1, wherein: Based on 100 parts by weight of the molecular weight broad distribution polypropylene, the content of the organic acid / anhydride is 0.5-1.5 parts by weight, the content of the organic metal salt is 0.3-1 parts by weight, and the content of the functional additive is 0.03-0.5 parts by weight.

9. The ion-modified broad molecular weight distribution polypropylene resin composition according to claim 1, wherein: The polypropylene resin composition has a PDI of ≥8.0, preferably ≥9.0, and an η0 of ≤8.0×10 4 Pa·s, preferably ≤5.5×10 4 Pa·s, melt strength at 210°C ≥ 0.20N, preferably ≥ 0.22N.

10. The method for preparing the ion-modified broad molecular weight distribution polypropylene resin composition according to any one of claims 1 to 9, characterized in that: The preparation method comprises: 1) mixing the broad molecular weight distribution polypropylene, the organic acid / acid anhydride and the organic metal salt, and extruding and granulating the mixture to obtain composite particles; 2) After mixing the composition particles with the functional additives, extrusion granulation is performed to obtain the ion-modified molecular weight wide distribution polypropylene resin composition.

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