Wood grain polypropylene composite material, preparation method and application thereof

Abstract

A kind of wood grain polypropylene composite material, by weight parts, including the following components: high fluidity polypropylene 45 parts;Metallocene low isotacticity polypropylene 5-15 parts;Wood powder 10-50 parts;Maleic anhydride grafted polypropylene 0.5-5 parts;Amide lubricant 0.5-2 parts;Dimethyl silicone oil 0.5-1.5 parts.The wood powder dispersion effect in the polypropylene composite material of the application is very good, so that the wood grain polypropylene composite material of the application has the advantages of wood grain, high gloss.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer materials, in particular to a wood grain polypropylene composite material and a preparation method and application thereof. BACKGROUND

[0002] The wood grain polypropylene has a wide range of applications, and the following are some common applications: widely used in the field of building, such as making furniture, tables and chairs, integrated cabinets, wardrobes, bookcases, air conditioner racks, wood-plastic indoor doors, floors, exterior wall panels, balcony railings, window frames, railings, etc.; packaging field, such as packaging trays, beverage boxes and various transportation turnover boxes; industrial field, which can be used as wear-resistant sheds for chemical industry and public places, casting models, machine covers, water pump shells, electrical materials, etc.; vehicle and ship field, automobile parts, automobile interior parts, ship interior decoration, boat, etc.

[0003] However, the wood grain polypropylene also has the following difficult-to-overcome defects:

[0004] 1. Limitations of strength and impact performance: the adhesion between hydrophilic wood powder and hydrophobic plastic is small, resulting in low mechanical strength of the product, smaller tensile strength and bending strength than when the plastic is not filled, greater brittleness than when the plastic is not filled, and lower impact strength. In addition, its density is usually higher than that of pure plastic and wood. In order to improve these performance defects, a coupling agent can be added to the formula to modify the surface of the wood powder, but the impact resistance and ductility, brittleness and density may not be greatly improved.

[0005] 2. Problems in processing:

[0006] Poor interfacial adhesion: the strong polarity and water absorption of wood powder and the non-polarity and hydrophobicity of most thermoplastic plastics result in poor compatibility between the two, and the interfacial adhesion is small. When the wood powder filling amount is large, the flowability and processability of the material are poor, the mixing and extrusion molding are difficult, the composite performance of wood plastic is affected, and the wood powder needs to be modified to improve the composite performance.

[0007] Due to the fluffy structure of wood powder, it is difficult to prepare wood grain polypropylene parts with smooth surface and high gloss when the temperature is higher than 170℃. SUMMARY

[0008] The purpose of the present application is to overcome the above technical defects, provide a wood grain polypropylene composite material with high surface gloss and good mechanical properties, and a preparation method and application thereof.

[0009] The present application is realized by the following technical scheme:

[0010] A wood grain polypropylene composite material, by weight, comprising the following components:

[0011] High flowability polypropylene 45 parts;

[0012]

[0013] In the wood grain polypropylene composite material, the high-fluidity polypropylene resin accounts for more than 40 wt% of the total weight percentage of the wood grain polypropylene composite material.

[0014] The high-fluidity polypropylene has a melt flow rate of 20-50 g / 10 min (test conditions: 230 DEG C / 2.16 kg) and an isotacticity of 94-96% according to the ISO 1133-1:2022 method.

[0015] The metallocene low-isotacticity polypropylene has an isotacticity of 55-65%.

[0016] Preferably, the metallocene low-isotacticity polypropylene has an isotacticity of 62-64%.

[0017] The test method for the isotacticity of polypropylene mainly uses infrared spectroscopy: the isotacticity is determined by analyzing the absorbance ratio of polypropylene at 998 cm -1 and 973 cm -1 .

[0018] The particle size of the wood powder is 70-400 mesh.

[0019] The type of wood powder is not limited in the present application, for example, pine powder with a trade name of WH-100 can be selected, and the particle size is 100-200 mesh.

[0020] In the maleic anhydride grafted polypropylene, the grafting rate of maleic anhydride is 1-10 wt%, preferably 3-5 wt%, wherein the polypropylene as the main chain can be homopolymer polypropylene with a trade name of PP HP500N, a melt flow rate of 12 g / 10 min (test conditions: 230 DEG C / 2.16 kg), and an isotacticity of 97%.

[0021] In the wood grain polypropylene composite material of the present application, the maleic anhydride grafted polypropylene can be a commercially available product or obtained by self-preparation, and the self-preparation method is as follows: according to the weight content of maleic anhydride, the maleic anhydride is heated and then injected into a twin-screw extruder containing molten polypropylene through an oil pump to obtain by reaction extrusion. The test method for maleic anhydride grafting is acid-base neutralization titration method, which utilizes the reaction property of maleic anhydride with alkali to calculate the grafting rate of maleic anhydride by titrating the consumed alkali amount.

[0022] The dimethyl silicone oil, i.e. polydimethylsiloxane, in the wood grain polypropylene composite material of the present application does not have a limited trade name, and common trade names are, for example, Japan Shin-Etsu KF-96-350CS and Wacker AK-350.

[0023] The amide lubricant is selected from at least one of ethylene bis fatty acid amide lubricant, erucic acid amide lubricant, oleic acid amide lubricant, and hydroxyl modified ethylene bis stearyl amide; the ethylene bis fatty acid amide lubricant is selected from at least one of ethylene bis fatty acid amide and ethylene bis stearyl amide; preferably, the amide lubricant is selected from hydroxyl modified ethylene bis stearyl amide.

[0024] The hydroxyl modified ethylene bis stearyl amide is to add hydroxyl groups in ethylene bis stearyl amide.

[0025] The antioxidant can be added or not according to actual conditions, and 0-2 parts of the antioxidant are added.

[0026] The antioxidant can be: 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene; 2,5-di-tert-butyl-4-hydroxybenzyl dimethylamine; diethyl-3,5-di-tert-butyl-4-hydroxybenzyl phosphate; stearyl-3,5-di-tert-butyl-4-hydroxybenzyl phosphate; 3,5-di-tert-butyl-4-hydroxyphenyl-3,5-di-stearyl-thio triazolyl amine; 2,6-di-tert-butyl-4-hydroxymethylphenol; 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylglycol allyl ether)-1,3,5-triazine; N,N'-hexamethylene di(3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide); N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine; octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; pentaerythritol tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; triethylene glycol di[3-(3,5-dimethyl-4-hydroxyphenyl)propionate]; triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate]; 2,2'-thiodiethyl-di[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, etc.

[0027] Further comprising 0-30 parts of glass fiber by weight.

[0028] The preparation method of the wood grain polypropylene composite material of the present application comprises the following steps: mixing each component according to the proportion, and then extruding and granulating through a double-screw extruder to obtain the wood grain polypropylene composite material. The screw temperature is set to 180-210 DEG C, and the rotating speed is 350-450 rpm.

[0029] The wood grain polypropylene composite material of the present application is used for preparing wood grain products.

[0030] The present application has the following beneficial effects:

[0031] The wood grain polypropylene composite material provided by the application is prepared by compounding high-fluidity polypropylene and metallocene low-crystallinity polypropylene, and can obtain high-gloss resin, and the compounding polypropylene resin and wood powder / maleic anhydride grafted polypropylene have better compatibility, and can obtain smooth-surface wood powder polypropylene under the joint action of ethylene bis fatty acid amide and dimethyl silicone oil. DETAILED DESCRIPTION

[0032] The application will be described in detail below in combination with specific examples. The following examples will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be pointed out that, for those skilled in the art, without departing from the concept of the application, a number of modifications and improvements can be made. These all belong to the protection scope of the application.

[0033] The raw materials used in the application are as follows:

[0034] Polypropylene A: high-fluidity polypropylene, melt flow rate is 30 g / 10 min (test conditions: 230 DEG C / 2.16 kg), brand is PP 320 powder, Hunan Balin Petrochemical, isotacticity is 95%.

[0035] Polypropylene B: metallocene low-crystallinity polypropylene, isotacticity is 60%, brand is L-MODUS 400;

[0036] Polypropylene C: metallocene low-crystallinity polypropylene, isotacticity is 63%, brand is PPT500;

[0037] Polypropylene D: ordinary low-crystallinity polypropylene, isotacticity is 68%, brand is PP C5608M;

[0038] Polypropylene E: metallocene medium-crystallinity polypropylene, isotacticity is 96%, brand is Purell HM671T;

[0039] Polypropylene F: metallocene high-crystallinity polypropylene, isotacticity is 99%, brand is Achieve 1605;

[0040] Polypropylene G: ordinary-fluidity polypropylene, CNOOC Shell Petrochemicals Co., Ltd., melt flow rate is 12 g / 10 min (test conditions: 230 DEG C / 2.16 kg), brand is PP HP500N; isotacticity is 97%.

[0041] Wood powder: pine powder, particle size is 150 mesh, brand is WH-100, from Jiangmen Xinhui District Shuangshui Town Mujiang Weihua Fragrance Factory;

[0042] Maleic anhydride grafted polypropylene A: mass grafting rate is 1.2 wt%, self-made;

[0043] Maleic anhydride grafted polypropylene B: grafting rate of 3wt%, self-made;

[0044] Maleic anhydride grafted polypropylene C: grafting rate of 5wt%, self-made;

[0045] Maleic anhydride grafted polypropylene D: grafting rate of 10wt%, self-made;

[0046] Maleic anhydride grafted polypropylene E: grafting rate of 0.5wt%, self-made;

[0047] Maleic anhydride grafted polypropylene F: grafting rate of 12wt%, self-made;

[0048] The self-made method of the above maleic anhydride grafted polypropylene is as follows: maleic anhydride is heated and then injected into a twin-screw extruder containing molten polypropylene by an oil pump according to the weight content of maleic anhydride, and then obtained by reaction extrusion. The polypropylene is selected from homopolymer polypropylene with a brand of PP HP500N, Haisi Petroleum Chemical Co., Ltd.

[0049] Maleic anhydride grafted polypropylene G: grafting rate of 1.2wt%, AD-105, Foshan Baimen High Polymer New Material Co., Ltd.;

[0050] Modified ethylene bis fatty amide: TAF, hydroxyl modified ethylene bis stearamide, Guangzhou Yuanya Chemical Co., Ltd.;

[0051] Ethylene bis stearamide: EBS, Guangzhou Runfeng Chemical Co., Ltd.;

[0052] Erdic acid amide: WK1890, Jiangxi Weike Oleochemical Co., Ltd.;

[0053] Oleic acid amide: WK1618, Jiangxi Weike Oleochemical Co., Ltd.;

[0054] Other lubricant A: ester lubricant, DP310, Lubrizol;

[0055] Other lubricant B: paraffin lubricant, LOXIOL 2050, Emery;

[0056] Other lubricant C: olefin lubricant, 617A, Honeywell;

[0057] Other lubricant D: fatty acid lubricant, ZINC STEARATE (BS-2818), BELIKE;

[0058] Dimethyl silicone oil: KF-96-350CS, Guangzhou Huisi Composite Material Co., Ltd., viscosity: 1800 mPa.s;

[0059] Vinyl silicone oil: TCP-8008, Guangzhou Tianci Silicone Technology Co., Ltd., viscosity: 1500 mPa.s;

[0060] Antioxidant: SONOX 1010, SONOX 168, Linyi Sanfeng Chemical Co., Ltd., Shandong.

[0061] Preparation method of wood grain polypropylene composite: according to the ratio, mix each component uniformly, extrude and granulate through a double screw extruder to obtain a wood grain polypropylene composite. The screw temperature is set to 180-210°C, and the rotation speed is 350-450 rpm.

[0062] Preparation method of the board for gloss and surface texture: the particles obtained by the double screw extruder are manufactured into 100x100x2.0mm square boards through a conventional injection molding machine and a specially designed mold.

[0063] Test methods:

[0064] (1) Gloss: test the 60° angle gloss of the square board using a gloss meter.

[0065] (2) Surface texture: use the roughness comparison block method to evaluate the surface texture of the square board, from best to worst, the grades are excellent, good, medium, and poor, and good and above can meet the requirements; where 'excellent': the surface texture is extremely uniform, delicate, and almost free of any visible unevenness or roughness; 'good': the surface texture is relatively uniform, and only a small amount of tiny unevenness can be observed under careful observation, and the overall smoothness is good;'medium': the surface texture is uneven to some extent, and the unevenness can be easily observed, and the smoothness is general; 'poor': the surface texture is rough and uneven, and the larger fluctuations can be clearly seen with the naked eye.

[0066] (3) Tensile strength: tested according to ISO 527-2:2012 standard;

[0067] (4) Notched impact strength: tested according to ISO 180:2023 standard.

[0068] Table 1: Component content (weight parts) and test results of wood grain polypropylene composite of Examples 1-7

[0069]

[0070]

[0071] From Examples 1 / 5 / 6 / 7 / 8, it is preferred that the weight content of maleic anhydride in the maleic anhydride grafted polypropylene is 3-5wt%.

[0072] It is preferred that the isotacticity of the metallocene low isotactic polypropylene is 62-64% according to Example 1 / 4.

[0073] Table 2: Content of each component of wood grain polypropylene composite material (parts by weight) and test results of Examples 8-11

[0074]

[0075]

[0076] It is known from Example 1 / 8 that the technical effect of the self-made raw material is similar to that of the commercially available maleic anhydride grafted polypropylene product.

[0077] It is known from Examples 1 / 9-11 that the gloss is higher and the mechanical properties are better when the ethylene bis fatty acid amide is modified.

[0078] Table 3: Content of each component of wood grain polypropylene composite material (parts by weight) and test results of Comparative Examples 1-6

[0079]

[0080] It is known from Examples 2 and Comparative Examples 1 / 2 / 3 that ordinary low isotactic polypropylene, metallocene medium isotactic polypropylene, and metallocene high isotactic polypropylene cannot be used to replace metallocene low isotactic polypropylene. The main reason is that the lower the isotacticity of polypropylene, the more likely the low isotactic polypropylene will float to the surface of the square plate when the material is finally made into a square plate by an injection molding machine, resulting in better gloss and surface texture.

[0081] It is known from Examples 2 and Comparative Example 4 that it is difficult to achieve full dispersion of wood powder when ordinary flowability polypropylene is used to replace high flowability polypropylene.

[0082] It is known from Examples 1 / 5 / 6 / 7 / 8 and Comparative Examples 5 / 6 that when the grafting rate of maleic anhydride of maleic anhydride grafted polypropylene is not within the range of 1-10 wt% according to the present application, the wood powder cannot be effectively dispersed and the bonding force with the resin cannot be effectively formed, resulting in poor gloss and surface texture of the obtained material.

[0083] Table 4: Content of each component of wood grain polypropylene composite material (parts by weight) and test results of Comparative Examples 7-12

[0084]

[0085] It is known from Comparative Example 7 that the use of vinyl silicone oil cannot achieve the purpose of the present application.

[0086] It is known from Comparative Example 8 that the dispersion of wood powder is poor when no ethylene bis fatty acid amide is used.

[0087] It can be seen from Comparative Example 9 that the adhesion between wood powder and resin matrix is poor when polypropylene grafted with maleic anhydride is selected. That is, when the polypropylene composite does not contain maleic anhydride grafted polypropylene with a specific grafting rate, the adhesion between wood powder and resin matrix becomes poor, resulting in a significant deterioration in the application performance of the polypropylene composite.

[0088] It can be seen from Comparative Example 10 that the mechanical properties are reduced when the content of maleic anhydride grafted polypropylene is too high.

[0089] It can be seen from Comparative Example 11 that when the content of metallocene low crystallinity polypropylene is too low, the dispersibility of wood powder is poor, which not only reduces the gloss and texture, but also reduces the mechanical properties.

[0090] It can be seen from Comparative Example 12 that when the content of metallocene low crystallinity polypropylene is too high, the tensile strength of the metallocene low crystallinity polypropylene itself is low, and the high content reduces the overall tensile strength, resulting in poor mechanical properties.

[0091] Table 5: Content of each component (parts by weight) and test results of wood grain polypropylene composites of Comparative Examples 13-16

[0092]

[0093] It can be seen from Comparative Examples 13-16 that other types of lubricants are insufficient for the dispersibility of wood powder, resulting in a deterioration in the application performance of the polypropylene composite, which cannot meet the application requirements.

Claims

1. A wood grain polypropylene composite, characterized by, By weight parts, comprising the following components: High flow polypropylene 45 parts; Metallocene low isotacticity polypropylene 5-15 parts; Wood powder 10-50 parts; Maleic anhydride grafted polypropylene 0.5-5 parts; Amide lubricant 0.5-2 parts; Dimethyl silicone oil 0.5-1.5 parts; The high flow polypropylene has a melt flow rate of 20-50 g / 10 min measured according to ISO 1133-1:2022 method, and the test conditions are 230℃ / 2.16kg. The isotacticity of the metallocene low isotacticity polypropylene is 55-65%.

2. The wood grain polypropylene composite of claim 1, wherein, The isotacticity of the metallocene low isotacticity polypropylene is 62-64%.

3. The wood-grain polypropylene composite of claim 1, wherein, The particle size of the wood powder is 70-400 mesh.

4. The wood-grain polypropylene composite of claim 1, wherein, The grafting rate of maleic anhydride in the maleic anhydride grafted polypropylene is 1-10wt%.

5. The wood-grain polypropylene composite of claim 4, wherein, The grafting rate of maleic anhydride in the maleic anhydride grafted polypropylene is 3-5wt%.

6. The wood-grain polypropylene composite of claim 1, wherein, The amide lubricant is selected from at least one of ethylene bis fatty acid amide lubricant, erucic acid amide lubricant, oleic acid amide lubricant, and hydroxy modified ethylene bis stearamide; the ethylene bis fatty acid amide lubricant is selected from at least one of ethylene bis fatty acid amide and ethylene bis stearamide.

7. The wood-grain polypropylene composite of claim 1, wherein The amide lubricant is selected from hydroxy modified ethylene bis stearamide.

8. The wood-grain polypropylene composite of claim 1, wherein, By weight parts, further comprising 0-2 parts of antioxidant; by weight parts, further comprising 0-30 parts of glass fiber.

9. Process for the production of the wood grain polypropylene composite according to any one of claims 1 to 8, characterized in that, According to the ratio, mix each component uniformly, extrude and granulate through a double screw extruder to obtain a wood grain polypropylene composite material.

10. Use of the wood grain polypropylene composite according to any one of claims 1 to 8, characterized in that, For preparing a wood grain product. For preparing a wood grain product.

Images