Low-odor TPV material and preparation method thereof

Abstract

The invention belongs to a new material technology, and particularly relates to a low-odor TPV material and a preparation method thereof.The preparation method comprises the steps that EPDM rubber, PP resin, a processing aid, color master batch and white oil are mixed and granulated, and master batch is obtained; dynamically vulcanizing the master batch in the presence of a vulcanizing agent and a vulcanizing accelerator to obtain the low-odor TPV material. Wherein the vulcanizing accelerator is prepared from one or two of trimethylolpropane trimethacrylate and trimethylolpropane triacrylate. In the prior art, an adsorption treatment method is mostly adopted for reducing the TPV odor, and obvious defects exist. On the basis of a TPV system, a new formula is researched and developed, and good mechanical properties of the material are kept while the odor is effectively reduced. According to the low-odor TPV material and the preparation method thereof, di-tert-butylperoxy isopropyl phenyl (BIBP) is combined with trimethylolpropane trimethacrylate and trimethylolpropane triacrylate to be used for EPDM rubber / PP resin / white oil, extrusion granulation is performed to obtain the low-odor TPV material, the odor level of the low-odor TPV material is found to be level 1 through conventional detection, and the problem that TPV emits odor is solved.

Description

Technical Field

[0001] The present invention belongs to new material technology, and specifically relates to a low-odor TPV material and a preparation method thereof. Background Art

[0002] With the development of industry, the processing and manufacturing of automotive parts have become more and more mature, including the extrusion and injection molding of TPV materials into products. TPV materials have the advantages of environmental protection, wide hardness range, good processing performance, and recyclability. However, TPV has a pungent smell of processing aids during processing. Nowadays, car companies have low-odor requirements for automotive parts, and low-odor TPV materials have become a future development trend. In order to reduce the odor of TPV, most of the existing technologies use adsorption treatment methods. For example, CN113980397A discloses a low-odor, low-VOC automotive TPV material and its preparation method. The addition of an adsorbent can further reduce the odor and VOC of the elastomer material, and its odor level is still above 3; CN117209903A discloses a low-odor TPV material and its preparation method. First, PP, EPDM, paraffin oil, talcum powder, and lubricating additives are mixed and granulated with a compatibilizer and masterbatch particles using a twin-screw extruder to prepare a semi-finished masterbatch, and then the semi-finished masterbatch is mixed and granulated with a vulcanizer and two deodorizers using a twin-screw extruder to prepare finished particles. The odor level is still above 3. Although the adsorbent can have a certain effect, it has obvious defects: it increases the cost, the adsorbent is difficult to be compatible with the plastic component, which causes it to affect the performance of the plastic product, and the deodorization effect is unstable. Therefore, it is necessary to develop a new formula based on the TPV system and maintain the good mechanical properties of the material. Summary of the invention

[0003] Most of the existing technologies hope to improve the odor of TPV materials by using adsorbents. This treatment method with only temporary treatment performance is difficult to achieve the removal of odor from the material. The present invention overcomes the technical prejudice of the existing technology that adsorbents are used for deodorization. Starting from the material formula, a low-odor TPV material and a preparation method thereof are creatively proposed. Through the combination of ingredients and proportions, the prepared product has a very small odor level and maintains the conventional mechanical properties of the TPV material.

[0004] The present invention adopts the following technical solution: A low-odor TPV material, the preparation method of which comprises the following steps: (1) EPDM rubber, PP resin, processing aid, masterbatch and white oil are mixed and granulated to obtain masterbatch; (2) The masterbatch is dynamically vulcanized in the presence of a vulcanizing agent and a vulcanizing accelerator to obtain a low-odor TPV material; The vulcanizing agent comprises one or two of trimethylolpropane trimethacrylate and trimethylolpropane triacrylate.

[0005] Preferably, the vulcanizing accelerator is trimethylolpropane trimethacrylate and trimethylolpropane triacrylate.

[0006] More preferably, the mass ratio of trimethylolpropane trimethacrylate to trimethylolpropane triacrylate is 1:(1-3), such as 1:2.

[0007] In the present invention, the processing aid includes one or more of a weathering agent, an antioxidant, and a lubricant.

[0008] In the present invention, the vulcanizing agent is a peroxide, including one or more of di-tert-butyl peroxide isopropylphenyl (BIBP), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (BIBP), and tert-butyl peroxyisopropyl carbonate (C75).

[0009] In the present invention, the mass ratio of EPDM rubber, PP resin, white oil, processing aid, masterbatch, vulcanizing agent and vulcanizing accelerator is (25-50): (10-25): (25-35): (1-2): (2-2.5): (1-3): (1-3).

[0010] Preferably, the mass ratio of EPDM rubber, PP resin, white oil, processing aid, masterbatch, vulcanizer and vulcanizing accelerator is (30-50): (15-25): (30-35): (1-2): (2-2.5): (1-2): (1-2).

[0011] Further preferably, the mass ratio of EPDM rubber, PP resin, white oil, processing aid, masterbatch, vulcanizer and vulcanizing accelerator is (35-45): (17-23): (30-35): (1-2): (2-2.5): (1-2): (1-2).

[0012] More preferably, the ratio of the amount of the vulcanizing agent to the amount of the vulcanizing accelerator is 1:(0.8-1.2), such as 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, etc.

[0013] The invention discloses application of the low-odor TPV material in preparing TPV products.

[0014] The invention discloses application of the low-odor TPV material in preparing TPV automobile products.

[0015] The invention discloses application of the low-odor TPV material in preparing TPV automobile interior products.

[0016] The invention discloses application of the low-odor TPV material in improving the odor of TPV products.

[0017] The invention discloses an automobile component, and the raw materials for preparing the automobile component include the low-odor TPV material disclosed by the invention.

[0018] In order to reduce the odor of TPV, most of the existing technologies use adsorption treatment methods, which have obvious defects: increased cost, the adsorbent is difficult to be compatible with the plastic components, causing it to affect the performance of plastic products, and the deodorization effect is unstable. Therefore, based on the TPV system, the present invention develops a new formula to effectively reduce the odor while maintaining the good mechanical properties of the material. The present invention uses di-tert-butyl peroxide isopropylbenzene (BIBP) combined with trimethylolpropane trimethacrylate and trimethylolpropane triacrylate for EPDM rubber / PP resin / white oil system, extrusion granulation to obtain low-odor TPV material. Conventional testing found that its odor level is as low as level 1, which solves the problem of TPV emitting odor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a photo of the actual appearance of the conventional sample preparation of the product in Example 1. DETAILED DESCRIPTION

[0020] The disadvantage of TPV in the prior art is that the particles have a pungent smell. Currently, most car interiors are made of TPV materials, which produce a pungent smell after being injected into the car interior. As people's living conditions improve, their requirements for cars are gradually getting higher. The first impression of opening a car is the smell. More and more customers require low odor in the car, and low-odor TPV is also born. However, the prior art uses adsorbents to improve the odor, which will bring problems with the preparation method and cost, and will also affect the performance of the TPV system. The present invention starts with the material formula and creatively adjusts the formula to effectively improve the TPV odor problem.

[0021] The method for preparing the low-odor TPV material of the present invention comprises the following steps: The first step is to make masterbatch: EPDM, PP resin, processing aids and masterbatch are fully mixed in a mixer and then put into a twin-screw extruder for processing. White oil is added into the extruder separately through a loss-in-weight metering scale. The speed is 350~400rpm and the temperature is 180~220℃ to make masterbatch; The second step is dynamic vulcanization: the masterbatch, vulcanizer and vulcanizing agent are mixed evenly and put into a twin-screw extruder at a speed of 380-400rpm and a temperature of 160-190℃ to form a product.

[0022] In the preparation method of the low-odor TPV material of the present invention, the formula composition is as follows in terms of mass percentage: EPDM rubber balance PP resin 10-25% White oil 25-35% Processing aids 1-2% Masterbatch 2-2.5% Vulcanizing agent (BIPB) 1-2% Vulcanizing agent (TMPTMA / PL400) 1-2% EPDM (ethylene propylene diene monomer) is a terpolymer with different Mooney viscosities formed by the polymerization of ethylene, propylene and non-conjugated diene; 3092PM was used in the experiment.

[0023] The PP resin is block copolymer polypropylene with a melt flow rate of 1 to 5 g / 10 min and a flexural modulus of ≥1300 MPa; K8003 was used in the experiment.

[0024] White oil: liquid hydrocarbon mixture, open flash point: 250~290℃; KP-100B is used for experiment.

[0025] Processing aids: a combination of commonly used weathering agents, antioxidants and lubricants. The weathering agents used in the experiment are equal amounts of 5590 and UV-234, the antioxidants are equal amounts of 1010 and 168, and the lubricants are equal amounts of PE wax and erucamide; the mass ratio of weathering agent: antioxidant: lubricant is 1:1:1.

[0026] Masterbatch: Colorant for polymer materials; 3050E for experiments.

[0027] Curing agent: di-tert-butyl peroxide isopropylbenzene (BIBP), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (BIBP) or tert-butyl peroxyisopropyl carbonate (C75).

[0028] Vulcanizing agent: TMPTMA (trimethylolpropane trimethacrylate), PL400 (trimethylolpropane triacrylate).

[0029] The formulas of the comparative examples and embodiments are shown in Table 1 and Table 2, and the specific processing methods are as follows: The first step is to make masterbatch: EPDM, PP resin, processing aid and masterbatch are mixed in a mixer and then put into a twin-screw extruder for processing. White oil is added into the extruder through a loss-in-weight metering scale. The speed is 400rpm, the temperature is 180~220℃, and the production capacity is 200kg / h to make masterbatch; The second step is dynamic vulcanization: the masterbatch, vulcanizer and vulcanizing agent are mixed evenly and put into a twin-screw extruder at a speed of 400 rpm, a temperature of 160-190°C and a production capacity of 180 kg / h to form a product.

[0030] Material testing method: Shore hardness: ISO 868:2023, 15 seconds reading; required to be greater than 65A; the example materials are all greater than 67A.

[0031] Tensile strength: ISO 37:2017, sample type dumbbell, test speed: 500mm / min; required to be greater than 6MPa; the materials in the examples are all greater than 6MPa.

[0032] The odor level adopts the conventional test method of the automobile factory. The test methods of each automobile factory are not exactly the same, but they are comparable to each other. The experiment of the present invention adopts: Q / BYDQ-A1901.404-2015. The lower the better. Sensoryly, the odor level of 1-1.5 is considered to be almost odorless.

[0033] Table 1: Formulas and properties of examples and comparative examples, Kg

[0034] Table 2 Example formulation and performance, Kg

[0035] Comparison Example The mechanical properties and odor level tests of similar products currently available on the market are as follows:

[0036] In the dynamic vulcanization reaction, the micro-particle rubber can no longer be combined into strips due to cross-linking. At the same time, the strip rubber is continuously changed into micro-particles by shearing, and finally vulcanized rubber particles are uniformly dispersed in the PP continuous phase. The most important step in the preparation process of TPV is the cross-linking of the rubber phase. After dynamic vulcanization, the size of the cross-linked EPDM particles gradually becomes regular and the distribution gradually becomes uniform. When no vulcanizer is added, the rubber does not produce cross-linking. The rubber phase in the blended elastomer is the continuous phase, the plastic phase is the dispersed phase, and the mechanical properties of TPV are poor. The experimental results show that the odor level of the three external water-cut materials used in existing production does not reach level 1, and the tensile strength is low; the vulcanizer has an effect on the mechanical properties of the product. The hardness of comparative example 3 is 65A and the tensile strength is 5MP; the combination of the vulcanizer and the vulcanizing agent has a significant effect on the odor level of TPV. The type of vulcanizer of the present invention is combined with the type of vulcanizing agent, and the basic formula of TPV is added. The product obtained by overall extrusion granulation has good performance, reduces the odor of the car, is beneficial to human health, and does not change the original properties of the material.

Claims

1. A method for preparing a low-odor TPV material, characterized in that: The following steps are involved: (1) EPDM rubber, PP resin, processing aid, masterbatch and white oil are mixed and granulated to obtain masterbatch; (2) The masterbatch is dynamically vulcanized in the presence of a vulcanizing agent and a vulcanizing accelerator to obtain a low-odor TPV material; The vulcanizing agent comprises one or two of trimethylolpropane trimethacrylate and trimethylolpropane triacrylate.

2. The method for preparing the low-odor TPV material according to claim 1, characterized in that: The vulcanizing agents are trimethylolpropane trimethacrylate and trimethylolpropane triacrylate.

3. The method for preparing the low-odor TPV material according to claim 2, characterized in that: The mass ratio of trimethylolpropane trimethacrylate to trimethylolpropane triacrylate is 1:(1-3).

4. The method for preparing the low-odor TPV material according to claim 1, characterized in that: The vulcanizing agent is peroxide.

5. The method for preparing the low-odor TPV material according to claim 1, characterized in that: The mass ratio of EPDM rubber, PP resin, white oil, processing aid, masterbatch, vulcanizing agent and vulcanizing accelerator is (25-50): (10-25): (25-35): (1-2): (2-2.5): (1-3): (1-3).

6. The method for preparing the low-odor TPV material according to claim 5, characterized in that: The ratio of the amount of vulcanizing agent to the amount of vulcanizing accelerator is 1: (0.8-1.2).

7. The low-odor TPV material prepared according to the method for preparing the low-odor TPV material according to claim 1.

8. Use of the low-odor TPV material according to claim 7 in the preparation of TPV products.

9. Use of the low-odor TPV material according to claim 7 in the preparation of TPV automobile products.

10. An automobile part, wherein the raw materials for preparing the automobile part include the low-odor TPV material according to claim 7.

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