Low-odor polypropylene composite material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of polymer composite materials, and particularly relates to a low-odor polypropylene composite material as well as a preparation method and application thereof. The low-odor polypropylene composite material comprises the following components: PP resin, a filler, an antioxidant, a lubricant and a deodorant COF (at) ZnO composite material, the COF material has a porous structure and regular pore channels, shows high porosity and high surface area, is rich in benzene ring structure, and adsorbs benzene series and other small molecular substances generated during melt extrusion of polypropylene by conjugate action and physical action; nano ZnO is dispersed on the surface of the COF material and can play a role in photocatalysis and degradation of VOCs substances, meanwhile, a COF framework can accelerate electron transfer to promote catalysis, odor improvement is achieved through the synergistic effect of nano ZnO and COF framework, and the problem that in the prior art, a polypropylene material volatilizes odorous gas is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer composite materials, and particularly relates to a low-odor polypropylene composite material and a preparation method and application thereof. Background Art

[0002] With the advancement of industrial technology, the engineering modification technology of polypropylene (PP) materials has developed rapidly. Using PP as a carrier, a certain amount of inorganic fillers and organic components are added during the extrusion granulation process to achieve the high performance of PP to meet the requirements of automotive parts. At present, modified PP parts have been widely used in various parts of the car, including dashboards, storage boxes, interior panels, etc., showing a series of advantages such as light weight, high strength, aging resistance, and corrosion resistance. However, in actual applications, such interior parts usually show a certain volatility, produce unpleasant gases in the car, deteriorate the air quality in the car, and have adverse effects on the user's experience and health.

[0003] At present, the solution to this problem is usually to add a vacuum extraction device or post-processing baking during the extrusion granulation process. Using vacuum or high temperature to remove small molecular odor substances requires additional equipment, is costly, and has poor effects. In addition, porous adsorbents such as activated carbon and silicates are added to the formula to adsorb volatile substances to solve the odor problem, but the efficiency of a single adsorbent is limited, the effect is weak, and the odor improvement is not obvious. Adding too much may affect the mechanical properties. Therefore, it is still necessary to research and develop a low-odor automotive polypropylene composite material. Summary of the invention

[0004] The object of the present invention is to provide a low-odor polypropylene composite material to solve the problem of volatile unpleasant gas emitted by polypropylene materials in the background art.

[0005] To achieve the above object, the present invention adopts the following technical solution: a low-odor polypropylene composite material, consisting of the following components in parts by weight:

[0006]

[0007]

[0008] The deodorant is a COF@ZnO composite material.

[0009] As a further improvement of low odor polypropylene composite materials:

[0010] Preferably, the filler is one or a combination of two or more of talc, calcium carbonate, barium sulfate, wollastonite and mica.

[0011] Preferably, the lubricant is one or a combination of two or more of silicone, stearate, and erucamide.

[0012] Preferably, the synthesis steps of the COF@ZnO composite material are as follows:

[0013] S1. Dissolve 1,3,5-tris(4-aminophenyl)benzene and terephthalaldehyde in a mixed solvent of 1,4-dioxane and 1,3,5-trimethylbenzene, then transfer the entire solution system to a reactor, heat to 110-120° C., maintain for 48-72 hours, and centrifuge, wash, soak, centrifuge and dry the reaction product to obtain a COF material;

[0014] S2. Disperse ZnO nanoparticles in anhydrous methanol at a concentration of 0.2-0.6 g / ml, stir to form a uniform suspension, add COF material, and after the ethanol evaporates completely, dry in an oven at 110-120° C. for 12-24 h to obtain a COF@ZnO composite material.

[0015] Preferably, the mass ratio of 1,3,5-tris(4-aminophenyl)benzene, terephthalaldehyde, 1,4-dioxane and 1,3,5-trimethylbenzene in step S1 is 6:3:500:100; and the mass ratio of COF material and ZnO nanoparticles in step S2 is 2:1.

[0016] Preferably, the reaction product in step S2 is centrifuged and then washed and soaked in acetone and tetrahydrofuran.

[0017] A second object of the present invention is to provide a method for preparing the low-odor polypropylene composite material described in any one of the above, comprising the following steps:

[0018] a. Weigh PP resin, filler, antioxidant, lubricant and deodorant according to the proportion, stir and mix at a speed of 300-500r / min for 5-10min to obtain a uniformly mixed material;

[0019] b. Put the uniformly mixed materials into a parallel twin-screw extruder for melting, extrusion and granulation to obtain a polypropylene composite material.

[0020] As the preparation method of low odor polypropylene composite material is further improved:

[0021] Preferably, the barrel temperature of the parallel twin-screw extruder is 180 to 220° C., the screw speed is 400 to 600 r / min, the melt pressure is 1.5 to 2.5 MPa, and the vacuum degree is -0.06 to -0.1 MPa.

[0022] The second and third objects of the present invention are to provide an application of any of the low-odor polypropylene composite materials described above in automotive interior decoration parts.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1) The present invention provides a low-odor polypropylene composite material, which includes PP resin, filler, antioxidant, lubricant and deodorant COF@ZnO composite material; through reasonable formula design, deodorant is added to the polypropylene composite material formula to prepare a low-odor polypropylene composite material. The deodorant is a COF@ZnO composite material, the COF material has a porous structure and regular pores, showing high porosity and high surface area, and is rich in benzene ring structure, which adsorbs benzene and other small molecules produced by polypropylene during melt extrusion by conjugation and physical action; nano ZnO is dispersed on the surface of the COF material, which can exert its photocatalytic effect to degrade VOCs substances, and the COF skeleton will also accelerate the transfer of electrons to promote catalysis, and the two can achieve odor improvement by synergistic effect.

[0025] 2) The present invention adopts COF@ZnO composite material as a deodorant, which is prepared by a solvent evaporation method. The technical principle of this method is that organic monomers, 3,5-tris(4-aminophenyl)benzene and terephthalaldehyde form a COF skeleton through a Schiff base reaction, and the unreacted amino groups and the hydroxyl groups on the surface of zinc oxide form hydrogen bonds, which are tightly combined and have a stable structure.

[0026] 3) The present invention also provides a method for preparing a low-odor polypropylene composite material. The preparation method has a simple process, can be mass-produced, and the odor of the extruded particles or products is significantly improved. DETAILED DESCRIPTION

[0027] For ease of understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] Table 1 Added weight parts of each component in Examples 1 to 5 and Comparative Examples 1 to 2

[0030]

[0031] Example 1

[0032] This embodiment provides a method for preparing a low-odor polypropylene composite material, which specifically includes the following steps:

[0033] (1) 0.6 g of 1,3,5-tris(4-aminophenyl)benzene and 0.3 g of terephthalaldehyde were dissolved in a mixed solvent of 50 g of 1,4-dioxane and 10 g of 1,3,5-trimethylbenzene, and then the entire solution system was transferred to a reactor, heated to 120°C, maintained for 72 hours, and then centrifuged, washed with acetone, soaked in tetrahydrofuran, centrifuged, and dried to obtain a COF material.

[0034] 20 g of ZnO nanoparticles (particle size of 10-55 nm, hexagonal wurtzite structure) were dispersed in 50 mL of anhydrous methanol with a dispersion concentration of 0.4 g / ml. After stirring for 1 hour, a uniform suspension was formed. 10 g of COF material was added to the above solution. Finally, after the ethanol was completely evaporated, it was dried in an oven at 110°C for 24 hours to obtain a COF@ZnO composite material.

[0035] (2) PP resin (MK51140T, Zhongsha Tianjin), filler, antioxidant, lubricant and deodorant were weighed according to the ratio in Table 1 and mixed at high speed to obtain a uniformly mixed material;

[0036] (3) The uniformly mixed materials are put into a parallel twin-screw extruder for melting and extrusion granulation to obtain a polypropylene composite material; the barrel temperature of the parallel twin-screw extruder is 180° C., the screw speed is 400 r / min, the melt pressure is 2.0 MPa, and the vacuum degree is -0.1 MPa.

[0037] The filler is talcum powder, the lubricant is calcium stearate, the antioxidant is a compound of hindered phenols and phosphites, specifically 1010 and 168, and the deodorant is a COF@ZnO composite material.

[0038] Example 2

[0039] This embodiment provides a method for preparing a low-odor polypropylene composite material, which specifically includes the following steps:

[0040] (1) 0.6 g of 1,3,5-tris(4-aminophenyl)benzene and 0.3 g of terephthalaldehyde were dissolved in a mixed solvent of 50 g of 1,4-dioxane and 10 g of 1,3,5-trimethylbenzene, and then the entire solution system was transferred to a reactor, heated to 110°C, maintained for 72 hours, and then centrifuged, washed with acetone, soaked in tetrahydrofuran, centrifuged, and dried to obtain a COF material.

[0041] 20 g of ZnO nanoparticles (particle size of 10-55 nm, hexagonal wurtzite structure) were dispersed in 50 mL of anhydrous methanol with a dispersion concentration of 0.4 g / ml. After stirring for 1 hour, a uniform suspension was formed. 10 g of COF material was added to the above solution. Finally, after the ethanol was completely evaporated, it was dried in an oven at 110°C for 24 hours to obtain a COF@ZnO composite material.

[0042] (2) PP resin (MK51140T, Zhongsha Tianjin), filler, antioxidant, lubricant and deodorant were weighed according to the ratio in Table 1 and mixed at high speed to obtain a uniformly mixed material;

[0043] (3) The uniformly mixed materials are put into a parallel twin-screw extruder for melting and extrusion granulation to obtain a polypropylene composite material; the barrel temperature of the parallel twin-screw extruder is 180° C., the screw speed is 400 r / min, the melt pressure is 2.0 MPa, and the vacuum degree is -0.1 MPa.

[0044] The filler is talcum powder, the lubricant is calcium stearate, the antioxidant is a compound of hindered phenols and phosphites, specifically 1010 and 168, and the deodorant is a COF@ZnO composite material.

[0045] Example 3

[0046] This embodiment provides a method for preparing a low-odor polypropylene composite material, which specifically includes the following steps:

[0047] (1) 6 g of 1,3,5-tris(4-aminophenyl)benzene and 3 g of terephthalaldehyde were dissolved in a mixed solvent of 500 g of 1,4-dioxane and 100 g of 1,3,5-trimethylbenzene, and then the entire solution system was transferred to a reactor, heated to 120° C., maintained for 72 h, and then centrifuged, washed with acetone, soaked in tetrahydrofuran, centrifuged, and dried to obtain a COF material.

[0048] 20 g of ZnO nanoparticles (particle size of 10-55 nm, hexagonal wurtzite structure) were dispersed in 50 mL of anhydrous methanol with a dispersion concentration of 0.4 g / ml. After stirring for 1 hour, a uniform suspension was formed. 10 g of COF material was added to the above solution. Finally, after the ethanol was completely evaporated, it was dried in an oven at 110°C for 24 hours to obtain a COF@ZnO composite material.

[0049] (2) PP resin (MK51140T, Zhongsha Tianjin), filler, antioxidant, lubricant and deodorant were weighed according to the ratio in Table 1 and mixed at high speed to obtain a uniformly mixed material;

[0050] (3) The uniformly mixed materials are put into a parallel twin-screw extruder for melting and extrusion granulation to obtain a polypropylene composite material; wherein the barrel temperature of the parallel twin-screw extruder is 180° C., the screw speed is 400 r / min, the melt pressure is 2.0 MPa, and the vacuum degree is -0.08 MPa.

[0051] Among them, the filler is talcum powder, the lubricant is zinc stearate, the antioxidant is a compound of hindered phenols and phosphites, specifically 1076 and 168, and the deodorant is a COF@ZnO composite material.

[0052] Example 4

[0053] This embodiment provides a method for preparing a low-odor polypropylene composite material, which specifically includes the following steps:

[0054] (1) 6 g of 1,3,5-tris(4-aminophenyl)benzene and 3 g of terephthalaldehyde were dissolved in a mixed solvent of 500 g of 1,4-dioxane and 100 g of 1,3,5-trimethylbenzene, and then the entire solution system was transferred to a reactor, heated to 120° C., maintained for 72 h, and then centrifuged, washed with acetone, soaked in tetrahydrofuran, centrifuged, and dried to obtain a COF material.

[0055] 20 g of ZnO nanoparticles (particle size of 10-55 nm, hexagonal wurtzite structure) were dispersed in 50 mL of anhydrous methanol with a dispersion concentration of 0.4 g / ml. After stirring for 1 hour, a uniform suspension was formed. 10 g of COF material was added to the above solution. Finally, after the ethanol was completely evaporated, it was dried in an oven at 110°C for 24 hours to obtain a COF@ZnO composite material.

[0056] (2) PP resin (MK51140T, Zhongsha Tianjin), filler, antioxidant, lubricant and deodorant were weighed according to the ratio in Table 1 and mixed at high speed to obtain a uniformly mixed material;

[0057] (3) The uniformly mixed materials are put into a parallel twin-screw extruder for melting and extrusion granulation to obtain a polypropylene composite material; wherein the barrel temperature of the parallel twin-screw extruder is 180° C., the screw speed is 400 r / min, the melt pressure is 2.0 MPa, and the vacuum degree is -0.08 MPa.

[0058] Among them, the filler is barium sulfate, the lubricant is calcium stearate, the antioxidant is a compound of hindered phenols and phosphites, specifically 1076 and 168, and the deodorant is a COF@ZnO composite material.

[0059] Comparative Example 1

[0060] The polypropylene composite material in this comparative example does not contain a deodorant, but only contains ZnO. The other components, component proportions, and preparation methods are the same as those in Example 1.

[0061] Comparative Example 2

[0062] The polypropylene composite material in this comparative example does not contain a deodorant, but only contains COF material. Other components and preparation methods are the same as those in Example 1.

[0063] Comparative Example 3

[0064] The polypropylene composite material in this comparative example does not contain any deodorant, and the other components and preparation method are the same as those in Example 1.

[0065] The polypropylene composite materials prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were tested for tensile strength, flexural strength, flexural modulus, and cantilever beam notched impact strength according to GB / T standards. The odor level test method was tested by referring to the German Volkswagen PV3900 test method. The specific method for the odor level test is as follows:

[0066] 20g of the above sample was placed in a test vessel and placed in an oven for 2h. The temperature of the oven was set at (80±2)℃. The test vessel must be sealed tightly. After the test vessel was taken out of the oven, it was cooled to 60℃, and the lid was slightly removed. The odor was evaluated by a professional odor assessor. The odor level of the material was divided into the following standards: Level 1: no odor, Level 2: odor, but no disturbing odor, Level 3: obvious odor, but no disturbing odor, Level 4: disturbing odor, Level 5: strong disturbing odor, and Level 6: unbearable odor. Physical test results of the composite materials of Examples 1-4 and Comparative Examples 1-3 are shown in Table 2.

[0067] Table 2 Physical test results of composite materials of Examples 1-4 and Comparative Examples 1-3

[0068]

[0069]

[0070] From the test results of Examples 1 to 4 and Comparative Examples 1 to 3 in Table 2, it can be seen that after adding the deodorant to the formula, as the deodorant content increases, the odor level increases significantly, and finally the odor level of the composite material can reach level 3.5, the odor situation is significantly improved, and the basic performance has not decreased, indicating that the introduction of the deodorant has little effect on the particles. In addition, it can also be seen that the deodorant COF@ZnO composite material has a better improvement in odor than the single component COF or ZnO, indicating that the two remove the volatiles generated during extrusion and injection molding through the synergistic effect of adsorption and catalysis, which is helpful for preparing low-odor polypropylene composite materials, which can be used in automotive interior parts.

[0071] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A low-odor polypropylene composite material, characterized in that: It is composed of the following components in parts by weight: PP resin 70-80 parts, 20-30 parts of filler, 0.2-0.5 parts of antioxidant, 0.2-0.5 parts of lubricant, 0.3-1 part of deodorant; The deodorant is a COF@ZnO composite material.

2. The low-odor polypropylene composite material according to claim 1, characterized in that: The filler is one or a combination of two or more of talc, calcium carbonate, barium sulfate, wollastonite and mica.

3. The low-odor polypropylene composite material according to claim 1, characterized in that: The lubricant is one or a combination of two or more of silicone, stearate and erucamide.

4. The low-odor polypropylene composite material according to claim 1, characterized in that: The synthesis steps of the COF@ZnO composite material are as follows: S1. Dissolve 1,3,5-tris(4-aminophenyl)benzene and terephthalaldehyde in a mixed solvent of 1,4-dioxane and 1,3,5-trimethylbenzene, then transfer the entire solution system to a reactor, heat to 110-120° C., maintain for 48-72 hours, and centrifuge, wash, soak, centrifuge and dry the reaction product to obtain a COF material; S2. Disperse ZnO nanoparticles in anhydrous methanol at a concentration of 0.2-0.6 g / ml, stir to form a uniform suspension, add COF material, and after the ethanol evaporates completely, dry in an oven at 110-120° C. for 12-24 h to obtain a COF@ZnO composite material.

5. The low-odor polypropylene composite material according to claim 4, characterized in that: The ZnO nanoparticles in step S2 have a particle size of 10 to 55 nm and a hexagonal wurtzite structure.

6. The low-odor polypropylene composite material according to claim 4, characterized in that: The mass ratio of 1,3,5-tris(4-aminophenyl)benzene, terephthalaldehyde, 1,4-dioxane and 1,3,5-trimethylbenzene in step S1 is 6:3:500:100; the mass ratio of COF material and ZnO nanoparticles in step S2 is 2:

1.

7. The low-odor polypropylene composite material according to claim 4, characterized in that: In step S2, the reaction product is centrifuged and then washed and soaked in acetone and tetrahydrofuran.

8. A method for preparing the low-odor polypropylene composite material according to any one of claims 1 to 7, characterized in that: The steps include: a. Weigh PP resin, filler, antioxidant, lubricant and deodorant according to the proportion, stir and mix at a speed of 300-500r / min for 5-10min to obtain a uniformly mixed material; b. The uniformly mixed materials are put into a parallel twin-screw extruder for melting, extrusion and granulation to obtain a polypropylene composite material.

9. The method for preparing the low-odor polypropylene composite material according to claim 8, characterized in that: The barrel temperature of the parallel twin-screw extruder is 180-220°C, the screw speed is 400-600r / min, the melt pressure is 1.5-2.5MPa, and the vacuum degree is -0.06--0.1MPa.

10. Use of the low-odor polypropylene composite material according to any one of claims 1 to 7 in automobile interior decoration parts.

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