A polypropylene composite material, its preparation method and application

Abstract

This invention relates to a polypropylene composite material, its preparation method, and its applications. The polypropylene composite material comprises the following components: polypropylene resin, POSS-modified polyamide, accelerator, coupling agent, mineral filler, and other additives. This polypropylene composite material exhibits good damping properties and dimensional stability, and can be widely used in the manufacture of automotive interior parts.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and more specifically, to a polypropylene composite material, its preparation method, and its application. Background Technology

[0002] With the rapid development of the automotive industry, the performance requirements for automotive materials are also increasing. Among them, damping characteristics and dimensional stability are two key performance indicators, which are crucial for ensuring good comfort, safety, and durability of automobiles during operation. For example, for automotive interior components, such as dashboards, center consoles, or electronic equipment mounting components like displays, these components need to have high damping characteristics to reduce vibration, while also maintaining dimensional stability to ensure assembly accuracy and aesthetics.

[0003] Polypropylene has outstanding advantages such as wide availability, low density, good mechanical balance, chemical corrosion resistance, easy processing and low price, and is widely used in automobile bumpers, door panels, pillar guards, seat guards, various dashboards and various automotive interiors.

[0004] During operation, vehicles are subjected to vibrations and impacts from the road surface, engine, and other moving parts. If the damping characteristics are insufficient, these vibrations will be transmitted into the vehicle interior, affecting passenger comfort and potentially causing fatigue and discomfort. Therefore, improving the damping properties of automotive materials has become an important goal for enhancing the vehicle's riding experience.

[0005] Vehicle components and structures require good dimensional stability, especially when facing environmental changes such as temperature and humidity. If materials are prone to dimensional changes under different environmental conditions, it may lead to loosening of parts, seal failure, or other performance problems, and even affect the safety and stability of the entire vehicle.

[0006] Traditional automotive materials often involve a trade-off between damping properties and dimensional stability. For example, some materials with high damping performance may perform poorly in terms of dimensional stability, while materials with good dimensional stability may lack sufficient damping capacity.

[0007] Patent CN109679215A provides a high-damping polypropylene material, but it does not focus on the dimensional stability of the material.

[0008] Therefore, it is necessary to develop a material that can simultaneously improve the damping properties and dimensional stability of automotive materials. Summary of the Invention

[0009] The primary objective of this invention is to overcome the problem that the damping properties and dimensional stability of existing polypropylene materials cannot be improved simultaneously, and to provide a polypropylene composite material.

[0010] A further object of the present invention is to provide a method for preparing the above-mentioned polypropylene composite material.

[0011] A further object of the present invention is to provide the application of the above-mentioned polypropylene composite material in the preparation of automotive interior parts.

[0012] The above-mentioned objective of the present invention is achieved through the following technical solution:

[0013] A polypropylene composite material comprising the following components in parts by weight:

[0014]

[0015] The accelerator comprises a poly(imide-ester-amide) copolymer and chlorinated polypropylene in a mass ratio of (0.85–4):1.

[0016] In this invention, the addition of mineral fillers can improve the basic mechanical properties of polypropylene composite materials and also contribute to the improvement of dimensional stability. Furthermore, the addition of a coupling agent can enhance the bonding force between the polypropylene resin and the mineral fillers.

[0017] This invention improves the dimensional stability of polypropylene composites by introducing POSS-modified polyamide and utilizing the entanglement and intermolecular hydrogen bonding between POSS nanoparticles and polyamide molecular chains. However, the poor compatibility between POSS-modified polyamide and the polypropylene system leads to poor dimensional stability of the polypropylene composites.

[0018] In addition, the inventors also discovered that although POSS has a cavity structure that can absorb some of the vibration energy, POSS itself has very high rigidity. The addition of POSS-modified polyamide will lead to a decrease in the damping performance of polypropylene composite materials.

[0019] Further research by the inventors revealed that, with the addition of POSS-modified polyamide and the aid of the accelerator in this invention, the polypropylene composite material exhibits both excellent dimensional stability and damping properties. The addition of chlorinated polypropylene and poly(imide-ester-amide) copolymer improves the compatibility between POSS-modified polyamide and polypropylene resin, enhances their bonding force, and the poly(imide-ester-amide) copolymer possesses high elasticity, exhibiting good elasticity and flexibility, thus simultaneously improving the damping properties and dimensional stability of the polypropylene composite material. Furthermore, the coupling agent also contributes to enhancing the bonding force between POSS-modified polyamide and polypropylene resin.

[0020] That is, the polypropylene composite material of the present invention has good damping characteristics and dimensional stability.

[0021] In this invention, polypropylene resin is used as the main resin, and its content accounts for more than 35 wt% of the polypropylene composite material.

[0022] Commonly used polypropylene resins in this field can be used in this invention.

[0023] Optionally, the melt flow rate of the polypropylene resin measured at 230°C and 2.16 kg is 10–100 g / 10 min.

[0024] In this invention, the melt flow rate of the polypropylene resin can be measured according to ISO 1133-1 2022.

[0025] Optionally, the mineral filler is at least one of talc, wollastonite, mica powder, calcium carbonate, or kaolin.

[0026] Optionally, the average particle size of the mineral filler is 5–30 μm.

[0027] Optionally, the POSS-modified polyamide is an octaamino POSS-modified polyamide.

[0028] Optionally, the general structural formula of the octaaminoPOSS in the octaaminoPOSS-modified polyimide is as follows:

[0029] Wherein, R is at least one of -CH2CH2CH2NH3Cl, -CH2CH2CH2NH2, -CH2CH2CH2NH(C6H5) or -(C6H4)-NH2.

[0030] Optionally, the polyamide in the POSS-modified polyamide is an aromatic polyamide.

[0031] Further optionally, the aromatic polyamide is a carboxyl-terminated aromatic polyamide.

[0032] Further optionally, the aromatic polyamide includes repeating units derived from aromatic diacyl chlorides and aromatic diamines.

[0033] Further optionally, the molar ratio of the aromatic diacyl chloride and the aromatic diamine is 1:(1.1 to 1.3).

[0034] Further optionally, the aromatic diacyl chloride is terephthaloyl chloride.

[0035] Further optionally, the aromatic diamine is one of p-phenylenediamine (p-PDA), m-phenylenediamine (MPD), and 3,3'-diaminodiphenyl sulfone (MPD).

[0036] Typically, the POSS-modified polyamide is prepared from carboxyl-terminated aromatic polyamide and octaamino POSS.

[0037] Optionally, the mass ratio of the octaaminoPOSS to the carboxyl-terminated aromatic polyamide is (0.2-0.6):1.

[0038] Optionally, the preparation method of the POSS-modified polyamide is as follows: aromatic diacyl chloride and aromatic diamine are added to organic solvent A for polycondensation reaction, and then POSS is added for acylation reaction to obtain the POSS-modified polyamide.

[0039] Typically, the polycondensation reaction takes 1 to 3 hours and is carried out at a temperature of 20 to 40°C.

[0040] Typically, the acylation reaction takes 1 to 3 hours and is carried out at a temperature of 10 to 30°C.

[0041] Optionally, the organic solvent A is one of γ-butyrolactone, tetrahydrofuran, dimethylacetamide, or dimethylformamide.

[0042] Preferably, the mass ratio of the poly(imide-ester-amide) copolymer to the chlorinated polypropylene is (1.5–2):1. Adjusting the mass ratio of chlorinated polypropylene to the poly(imide-ester-amide) copolymer within this range results in polypropylene composite materials with better damping properties and dimensional stability.

[0043] Optionally, the chlorinated polypropylene has a chlorine content of 20-40 wt%.

[0044] Preferably, the chlorine content of the chlorinated polypropylene is 35-40 wt%. By controlling the chlorine content of the chlorinated polypropylene within this range, the resulting polypropylene composite material exhibits better damping characteristics and dimensional stability.

[0045] In this invention, the chlorine content of the chlorinated polypropylene can be determined by oxygen flask combustion-potential titration.

[0046] Optionally, the poly(imide-ester-amide) copolymer includes imide bonds, ester bonds and amide bonds, and the molar ratio of the imide bonds, the ester bonds and the amide bonds is (32-50):(20-30):(25-40).

[0047] Preferably, the molar ratio of the imide bond, the ester bond, and the amide bond is (33–42):(22–30):(35–38). Adjusting the molar ratio of each chemical bond within this range results in a polypropylene composite material with better damping characteristics.

[0048] Optionally, the poly(imide-ester-amide) copolymer is obtained by reacting monomers that form imide bonds, monomers that form ester bonds, and monomers that form amide bonds. The synthesis method of the poly(imide-ester-amide) copolymer can be selected from existing polymerization processes and process conditions according to the types of monomers.

[0049] Optionally, the poly(imide-ester-amide) copolymer can be prepared by the following method:

[0050] The monomers constituting the imide bond and the monomers constituting the ester bond are added to organic solvent B, and a first polymerization reaction is carried out at 20-30°C for 3-5 hours; then the monomers constituting the amide bond are added, and a second polymerization reaction is carried out at 20-30°C for 10-15 hours; then a dehydration cyclization reaction is performed to obtain a poly(imide-ester-amide) copolymer.

[0051] Preferably, the dehydration cyclization reaction is followed by steps of cooling, precipitation, and drying.

[0052] More preferably, the cooling temperature is room temperature (20-35°C); the precipitant used for precipitation includes, but is not limited to, ethanol; and the drying temperature is 50-70°C.

[0053] Specifically, the dehydration cyclization reaction may include the following steps: adding a dehydrating agent (such as acetic anhydride) and a catalyst (such as pyridine) to the reaction solution after the second polymerization reaction, and reacting for 2 to 5 hours at a temperature of 70 to 100°C.

[0054] Optionally, the monomers constituting the imide bond include aromatic diamine monomers and tetracarboxylic dianhydride monomers.

[0055] Optionally, the monomers constituting the ester bond include tetracarboxylic dianhydride monomers containing ester groups and / or diamine monomers containing ester groups.

[0056] Optionally, the monomers constituting the amide bond include aromatic diacyl chloride monomers and aromatic diamine monomers.

[0057] Optionally, the organic solvent B is N-methylpyrrolidone (NMP).

[0058] The tetracarboxylic dianhydride monomer that forms the imide bond can be the same as or different from the tetracarboxylic dianhydride monomer containing the ester group that forms the ester bond. Similarly, the aromatic diamine monomer that forms the imide bond, the aromatic diamine monomer that forms the amide bond, and the diamine monomer containing the ester group that forms the ester bond can be the same as or different from each other.

[0059] Optionally, the aromatic diamine monomer is at least one of p-phenylenediamine (p-PDA), m-phenylenediamine (MPD), 3,3'-diaminodiphenyl sulfone (MPD), or 2,2'-bis(trifluoromethyl)diaminobiphenyl (TFMB).

[0060] Optionally, the tetracarboxylic dianhydride monomer is at least one selected from 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 4,4'-(hexafluoroisopropene)phthalic anhydride (6FDA), and 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA).

[0061] Optionally, the aromatic diacyl chloride monomer is at least one selected from terephthaloyl chloride (TPC), isophthaloyl chloride, 4,4'-biphenyl dicarboxylate chloride, or 2,2'-biphenyl dicarboxylate chloride.

[0062] Optionally, the monomer constituting the ester bond is at least one of hydroquinone bis(triphenyltrihydride) TAHQ (TAHQ) and 1,4-cyclohexylene bis(triphenyltrihydride) (TACH).

[0063] Optionally, the coupling agent is a silane coupling agent, including but not limited to at least one of γ-aminopropyltriethoxysilane or γ-glycidoxypropyltrimethoxysilane.

[0064] Optionally, the other additives are at least one of antioxidants or lubricants.

[0065] Optionally, the antioxidant is at least one of antioxidant 1010, antioxidant 168, and antioxidant DSTP.

[0066] Optionally, the lubricant is at least one of stearic acid EBS, silicone, and PE wax.

[0067] The preparation method of the above-mentioned polypropylene composite material includes the following steps: mixing the components, melt extruding, and granulating to obtain the polypropylene composite material.

[0068] Generally, the temperature of the melt extrusion is 190–230°C.

[0069] The application of the aforementioned polypropylene composite material in the preparation of automotive interior parts is also within the scope of protection of this invention.

[0070] Compared with the prior art, the beneficial effects of the present invention are:

[0071] The polypropylene composite material of the present invention has good damping properties and dimensional stability, and can be widely used in the preparation of automotive interior parts. Detailed Implementation

[0072] To more clearly and completely describe the technical solution of the present invention, the present invention will be further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention. Various changes can be made within the scope of the claims of the present invention.

[0073] The reagents used in the various embodiments and comparative examples of this invention are described below:

[0074] Polypropylene resin 1#: The melt flow rate is 10g / 10min under the conditions of 230℃ and 2.16kg. It is a copolymer polypropylene resin, PP EP300M, and is manufactured by Sinopec.

[0075] Polypropylene resin #2: Melt flow rate of 100g / 10min at 230℃ and 2.16kg, copolymer polypropylene resin, PP BX3920, SK Chemicals Co., Ltd., South Korea;

[0076] POSS: Ammonia-terminated POSS, purchased from BEHTA TECH in Iran;

[0077] AM0285, Hybrid Plastics, OctaAmmoniumPOSS, has the following structural formula:

[0078]

[0079] POSS-modified polyamide 1# (POSS-PA-1#): Self-made, the preparation method is as follows: 1) In a container equipped with a stirrer, thermometer and nitrogen purging device, p-PDA and TPC are mixed at a molar ratio of 1:1.2 and added to the organic solvent dimethylacetamide. The mixture is stirred at 30°C for 2 hours to prepare carboxyl-terminated polyamide (PA1#); 2) Ammonia-terminated POSS and PA1# are mixed at a mass ratio of 0.2:1 and stirred evenly. The mixture is then reacted at 25°C for 2 hours. The solid is obtained by filtration and vacuum drying for 24 hours to obtain POSS-modified polyamide 1#.

[0080] POSS-modified polyamide 2# (POSS-PA-2#): self-made, the preparation method is basically the same as that of POSS-modified polyamide 1#, the difference is: 2) amino-terminated POSS and PA1# are mixed in a mass ratio of 0.6:1.

[0081] POSS modified polyamide 3# (POSS-PA-3#): self-made, the preparation method is basically the same as that of POSS modified polyamide 1#, the difference is that p-PDA in step 1) is replaced with MPD.

[0082] Poly(imide-ester-amide) copolymer-1#: self-made, preparation method is as follows:

[0083] 1) In a container equipped with a stirrer, thermometer and nitrogen purging device, N-methylpyrrolidone (NMP) was added to the reactor; after setting the reactor temperature to 25°C, 2,2'-bis(trifluoromethyl)diaminobiphenyl (TFMB) was dissolved in NMP, and then hydroquinone bis(triphenyltrihydride) (TAHQ) and 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride (CBDA) were added, and the mixture was stirred at 25°C for 4 hours to carry out the reaction; then terephthaloyl chloride (TPC) was added, and the reaction was carried out at 25°C for 12 hours to obtain a solution containing poly(imide-ester-amide) copolymer.

[0084] 2) Pyridine and acetic anhydride were added to a solution containing the poly(imide-ester-amide) copolymer, and the mixture was stirred until homogeneous. The mixture was then stirred at 85°C for 4 hours. The reaction solution was cooled to room temperature and precipitated with 5 liters of ethanol. The precipitated solid was dried at 60°C to obtain the poly(imide-ester-amide) copolymer. The molar ratio of imide bonds, ester bonds, and amide bonds in the obtained poly(imide-ester-amide) copolymer was 40:24:36.

[0085] Poly(imide-ester-amide) copolymer-2#: self-made, the preparation method is basically the same as that of poly(imide-ester-amide) copolymer-1#. By changing the amount of raw materials, the molar ratio of imide bonds, ester bonds and amide bonds of the obtained poly(imide-ester-amide) copolymer is 33:30:37.

[0086] Poly(imide-ester-amide) copolymer-3#: self-made, the preparation method is basically the same as that of poly(imide-ester-amide) copolymer-3#. By changing the amount of raw materials, the molar ratio of imide bonds, ester bonds and amide bonds of the obtained poly(imide-ester-amide) copolymer is 48:27:25.

[0087] Chlorinated polypropylene #1: Shiteng Chemical, H10-38, chlorine content 38%;

[0088] Chlorinated polypropylene #2: Toyobo, Japan, F-2P, chlorine content 20%;

[0089] Coupling agent: silane coupling agent, γ-aminopropyltriethoxysilane, commercially available;

[0090] Mineral filler: Talc powder, TYT-8875B, average particle size 8μm, Haicheng Tianyuan Chemical Co., Ltd.;

[0091] Other adjuvants #1: Antioxidant, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], commercially available;

[0092] Other additives #2: Lubricant, ethylene bis-stearamide, commercially available.

[0093] Unless otherwise specified, all components (e.g., other additives, coupling agents, mineral fillers) used in each parallel example and comparative example are the same commercially available products.

[0094] The polypropylene composite materials of the embodiments and comparative examples of the present invention were prepared by the following preparation method:

[0095] Weigh each component according to the formula; mix each component in a high-speed mixer for 4 minutes to obtain a mixture; then feed the mixture into a twin-screw extruder through the main feed port, and after melt extrusion, stranding, water cooling, and granulation, obtain the polypropylene composite material. The temperatures of each zone in the twin-screw melt extrusion are: Zone 1 100℃, Zone 2 200℃, Zone 3 220℃, Zone 4 220℃, Zone 5 220℃, Zone 6 220℃, Zone 7 220℃, Zone 8 220℃, and Zone 9 220℃.

[0096] The performance of the polypropylene composite materials provided in the embodiments and comparative examples of this invention was determined according to the following test methods:

[0097] (1) Damping performance: Polypropylene composite material was injection molded into a strip and tested using TA's DMA Q800 dynamic mechanical analyzer. The test temperature range was -50℃ to 80℃, the heating rate was 2℃ / min, and the frequency was 10Hz. The average tanδ under the test range was calculated. The larger the tanδ value, the better the damping performance.

[0098] (2) Dimensional stability: A 200mm*50mm*2mm sample was injection molded and subjected to the following heat and cold treatment: after cooling for 24 hours, it was placed in a 100℃ oven for 8 hours, then removed and placed at -10℃ for 8 hours, and then removed and placed at room temperature for 4 hours. The dimensional change rate of the sample in the length direction before and after the heat and cold treatment was recorded and calculated.

[0099] Examples 1-13

[0100] Examples 1-13 provide a series of polypropylene composite materials, the formulations of which are shown in Tables 1 and 2.

[0101] Table 1. Formulations (parts by weight) for Examples 1-7

[0102]

[0103]

[0104] Table 2. Formulations (parts by weight) for Examples 8-13

[0105]

[0106] Comparative Examples 1-6

[0107] Comparative Examples 1–6 provide a series of polypropylene composite materials, the formulations of which are shown in Table 3.

[0108] Table 3 shows the formulations (parts by weight) for Comparative Examples 1–6.

[0109]

[0110]

[0111] PA1# in Table 3 comes from step 1) of the preparation process of POSS modified polyamide 1#.

[0112] The properties of the polypropylene composite materials of each embodiment and comparative example were determined according to the test methods mentioned above, and the test results are shown in Table 4.

[0113] Table 4. Performance test results of polypropylene composite materials in each example and comparative example.

[0114] Test Results average tanδ Dimensional change rate (%) Example 1 0.43 0.08 Example 2 0.43 0.09 Example 3 0.39 0.07 Example 4 0.44 0.10 Example 5 0.35 0.11 Example 6 0.31 0.09 Example 7 0.36 0.13 Example 8 0.45 0.07 Example 9 0.38 0.12 Example 10 0.32 0.14 Example 11 0.36 0.11 Example 12 0.39 0.15 Example 13 0.41 0.12 Comparative Example 1 0.09 0.23 Comparative Example 2 0.11 0.19 Comparative Example 3 0.05 0.25 Comparative Example 4 0.06 0.31 Comparative Example 5 0.04 0.28 Comparative Example 6 0.05 0.30

[0115] As can be seen from Table 4:

[0116] The average tanδ of the polypropylene composites in Examples 1 to 13 is above 0.31, and the dimensional change rate is below 0.15, indicating that the polypropylene composites of the present invention have good damping characteristics and dimensional stability.

[0117] Comparative Example 1, using an accelerator that did not contain poly(imide-ester-amide) copolymer, resulted in a polypropylene composite material with poor damping properties and dimensional stability. Comparative Example 2, using an accelerator that did not contain chlorinated polypropylene, also resulted in a polypropylene composite material with poor damping properties and dimensional stability. Comparative Example 3, using no accelerator, resulted in a polypropylene composite material with both poor damping properties and dimensional stability. Comparative Example 4, using no POSS-modified polyamide, resulted in a polypropylene composite material with both poor damping properties and dimensional stability. Comparative Example 5, using POSS directly, resulted in a polypropylene composite material with both poor damping properties and dimensional stability. Comparative Example 6, using unmodified polyamide, resulted in a polypropylene composite material with both poor damping properties and dimensional stability.

[0118] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A polypropylene composite material, characterized in that, The components include the following parts by weight: 50-80 parts of polypropylene resin, 20-35 parts of octaaminoPOSS-modified polyamide, Accelerator 10-20 parts, 3-8 parts of coupling agent, 5-30 parts of mineral filler Other auxiliary agents: 0-5 parts; The polyamide in the octaaminoPOSS-modified polyamide is an aromatic polyamide; the general structural formula of the octaaminoPOSS in the octaaminoPOSS-modified polyimide is as follows: Wherein, R is at least one of -CH2CH2CH2NH3Cl, -CH2CH2CH2NH2, -CH2CH2CH2NH(C6H5) or -(C6H4)-NH2; The accelerator comprises a poly(imide-ester-amide) copolymer and chlorinated polypropylene in a mass ratio of (0.85~4):1; the poly(imide-ester-amide) copolymer comprises imide bonds, ester bonds and amide bonds, and the molar ratio of the imide bonds, the ester bonds and the amide bonds is (32~50):(20~30):(25~40); the poly(imide-ester-amide) copolymer is obtained by reacting monomers constituting imide bonds, monomers constituting ester bonds and monomers constituting amide bonds; the monomers constituting imide bonds include aromatic diamine monomers and tetracarboxylic dianhydride monomers; the monomers constituting ester bonds include tetracarboxylic dianhydride monomers containing ester groups and / or diamine monomers containing ester groups; the monomers constituting amide bonds include aromatic diacyl chloride monomers and aromatic diamine monomers.

2. The polypropylene composite material according to claim 1, characterized in that, The melt flow rate of the polypropylene resin measured at 230℃ and 2.16kg was 10~100g / 10min.

3. The polypropylene composite material according to claim 1, characterized in that, The mineral filler is at least one of talc, wollastonite, mica powder, calcium carbonate, or kaolin.

4. The polypropylene composite material according to claim 1, characterized in that, The mass ratio of the poly(imide-ester-amide) copolymer to chlorinated polypropylene is (1.5~2):

1.

5. The polypropylene composite material according to claim 1, characterized in that, The chlorinated polypropylene has a chlorine content of 20-40 wt%.

6. A method for preparing the polypropylene composite material according to any one of claims 1 to 5, characterized in that, The process includes the following steps: mixing the components, melt extruding, and granulating to obtain the polypropylene composite material.

7. The use of the polypropylene composite material according to any one of claims 1 to 5 in the preparation of automotive interior parts.

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