Polymethyl methacrylate composite material as well as preparation method and application thereof

Abstract

The invention relates to a polymethyl methacrylate composite material as well as a preparation method and application thereof, and belongs to the technical field of compositions of high-molecular compounds. The polymethyl methacrylate composite material comprises the following components in parts by weight: 70-95 parts of PMMA resin, 2-15 parts of a toughening agent, 3-10 parts of activated shell powder and 1.2-6 parts of a functional additive, the specific surface area of the activated shell powder is greater than or equal to 0.8 m < 2 > / g; the functional additive comprises at least one of an antibacterial agent, a lubricant, an antioxidant and a weather-resistant agent. The polymethyl methacrylate composite material has high wear resistance and high toughness, and the surface of the polymethyl methacrylate composite material is not easy to absorb moisture and become sticky.

Description

Technical Field

[0001] The present invention relates to the technical field of compositions of polymer compounds, and particularly relates to a polymethyl methacrylate composite material, a preparation method thereof, and an application thereof. Background Art

[0002] At present, most of the materials of mahjong tiles on the market are melamine resins (melamine formaldehyde resins). However, in an environment with high humidity, the surface of the mahjong tiles made of such melamine resins is prone to absorb moisture and become sticky, showing a sticky feeling in the hand, which seriously affects the experience of players. Polymethyl methacrylate (PMMA) is an amorphous transparent resin, which itself has high mechanical strength, surface hardness, and high dimensional stability and is easy to mold, showing great application potential in the field of mahjong tile manufacturing. However, the main problem faced by PMMA materials in mahjong tile applications is that their performance is brittle and their wear resistance is worse than that of melamine resins. Therefore, it is necessary to develop PMMA materials with high wear resistance, high toughness, and a surface that is not easy to absorb moisture to meet the use requirements of mahjong tiles. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a polymethyl methacrylate composite material, a preparation method thereof, and an application thereof.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] In the first aspect, the present invention provides a polymethyl methacrylate composite material, which comprises the following components by weight: 70-95 parts of PMMA resin, 2-15 parts of toughening agent, 3-10 parts of activated shell powder, and 1.2-6 parts of functional additive; the specific surface area of the activated shell powder ≥ 0.8 m 2 / g; the functional additive includes at least one of antibacterial agent, lubricant, antioxidant, and weather resistance agent.

[0006] The present invention combines a specific activated shell powder with PMMA resin and a toughening agent. The porous fibrous double helix structure of the activated shell powder enables the polymethyl methacrylate composite material to easily adsorb moisture to form a water film in a high humidity environment, so as to prevent moisture from aggregating and condensing on the surface of the polymethyl methacrylate composite material. Moreover, the activated shell powder can also adsorb small molecule additives migrating to the surface in the polymethyl methacrylate composite material, thereby significantly improving the surface moisture absorption and stickiness of the polymethyl methacrylate composite material. Moreover, the combination of the activated shell powder and the toughening agent can not only maintain the good toughening effect of the toughening agent to improve the toughness of the polymethyl methacrylate composite material, but also effectively improve the surface hardness of the polymethyl methacrylate composite material, so that the polymethyl methacrylate composite material has high wear resistance, high toughness, and a surface that is not easy to absorb moisture and become sticky.

[0007] It should be noted that the main component of the activated shell powder is calcium carbonate (its mass percentage content ≥ 90%), and it also contains calcium phosphate and trace elements (such as silicon, magnesium, potassium, zinc, manganese, copper, iron, etc.); the specific surface area of the activated shell powder can be measured by GB / T 19587-2017 "Determination of Specific Surface Area of Solid Materials by Gas Adsorption BET Method".

[0008] Optionally, the weight parts of PMMA resin in the above-mentioned polymethyl methacrylate composite material can specifically be 70 parts, 73 parts, 75 parts, 78 parts, 80 parts, 82 parts, 85 parts, 88 parts, 90 parts, 93 parts, 95 parts; the weight parts of the toughening agent can specifically be 2 parts, 4 parts, 6 parts, 8 parts, 10 parts, 13 parts, 15 parts; the weight parts of the activated shell powder can specifically be 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts. The mass percentage content of PMMA resin in the polymethyl methacrylate composite material ≥ 65%.

[0009] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, in the components of the polymethyl methacrylate composite material, the PMMA resin is 78 - 88 weight parts, the toughening agent is 5 - 12 weight parts, and the activated shell powder is 5 - 8 weight parts.

[0010] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the average particle size of the activated shell powder is 2.5 - 6.5 μm. Optionally, the average particle size of the activated shell powder can specifically be any one or any range value between any two of 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm. The average particle size of the activated shell powder can be measured by GB / T 19077-2016 "Particle Size Distribution - Laser Diffraction Method".

[0011] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the specific surface area of the activated shell powder is 0.8 - 3.2 m 2 / g. Optionally, the specific surface area of the activated shell powder can specifically be 0.8 m 2 / g, 1 m 2 / g, 1.2 m 2 / g, 1.4 m 2 / g, 1.6 m 2 / g, 1.8 m 2 / g, 2 m 2 / g, 2.2 m 2 / g, 2.4 m 2 / g, 2.6 m 2 / g, 2.8 m 2 / g, 3 m 2 / g, 3.2 m 2 The range value of any one or both of them in / g.

[0012] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the PMMA resin adopts the ISO1133-2012 standard, and the melt mass flow rate under the conditions of 230 °C and 3.8 kg is 1-20 g / 10 min. Optionally, the melt mass flow rate of the PMMA resin can specifically be the range value of any one or both of 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, 5 g / 10 min, 6 g / 10 min, 7 g / 10 min, 8 g / 10 min, 9 g / 10 min, 10 g / 10 min, 12 g / 10 min, 14 g / 10 min, 16 g / 10 min, 18 g / 10 min, 20 g / 10 min.

[0013] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the activated shell powder is obtained by calcining shell powder in an air atmosphere at 300-500 °C for 1-3 h. Optionally, the temperature of the calcination treatment can specifically be the range value of any one or both of 300 °C, 350 °C, 400 °C, 450 °C, 500 °C; the time of the calcination treatment can specifically be the range value of any one or both of 1 h, 1.5 h, 2 h, 2.5 h, 3 h.

[0014] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the surface of the activated shell powder is coated with a coupling agent. The coupling agent coated on the surface of the activated shell powder is beneficial to its uniform dispersion in the polymethyl methacrylate composite material, avoiding the agglomeration of the activated shell powder, and thus better improving the wear resistance of the polymethyl methacrylate composite material.

[0015] In addition, an antibacterial agent can be filled into the activated shell powder or directly incorporated into the material; when the antibacterial agent is filled into the activated shell powder, the antibacterial agent in the pores of the activated shell powder can gradually migrate to the surface of the polymethyl methacrylate composite material during use, thereby improving the continuous antibacterial performance of the polymethyl methacrylate composite material.

[0016] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the mass fraction of the coupling agent relative to the activated shell powder is 0.2%-0.6%; and / or, the coupling agent includes at least one of a silane coupling agent and a titanate coupling agent. Optionally, the mass fraction of the coupling agent relative to the activated shell powder can specifically be the range value of any one or both of 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, 0.6%.

[0017] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the toughening agent includes at least one of ABS rubber powder (wherein the mass content of butadiene is 50% - 65%), acrylate rubber (for example, it can be copolymerized from at least one of ethyl acrylate, butyl acrylate, ethylene-acrylate and other monomers (containing functional groups such as epoxy, fluorine, acrylonitrile, chlorine, etc.)), and silicone rubber; and / or, the antibacterial agent includes at least one of silver ion antibacterial agent, copper ion antibacterial agent, and zinc ion antibacterial agent.

[0018] As a preferred embodiment of the polymethyl methacrylate composite material of the present invention, the lubricant includes at least one of vinyl bisstearamide, erucamide, and stearate, preferably erucamide; the antioxidant includes at least one of hindered phenol antioxidants and phosphite antioxidants; the weathering agent includes at least one of hindered amine light stabilizers, benzotriazole light stabilizers, benzophenone light stabilizers, and triazine light stabilizers.

[0019] In a second aspect, the present invention provides a method for preparing the above polymethyl methacrylate composite material, comprising the following steps: mixing the components evenly and then melt-extruding to obtain the polymethyl methacrylate composite material.

[0020] Optionally, a twin-screw extruder can be used for melt-extrusion in the above preparation method. The length-diameter ratio of the twin-screw extruder is (40 - 44):1; the rotation speed of the twin-screw extruder is 300 - 500 revolutions per minute, and the pressure is 2 - 3 MPa; the temperature of the twin-screw extruder is 220 - 240 °C.

[0021] In a third aspect, the present invention provides the application of the above polymethyl methacrylate composite material in the preparation of toys, household items, electronic components, household appliances, gardening equipment, medical technology equipment, motor vehicle parts or vehicle body parts. In particular, the above polymethyl methacrylate composite material is used in the preparation of parts with excellent toughness, surface hardness and not easy to absorb moisture and become sticky; specifically, it can be used to prepare mahjong tiles.

[0022] In a fourth aspect, the present invention provides a mahjong tile shell, and the material of the mahjong tile shell includes the above polymethyl methacrylate composite material.

[0023] In a fifth aspect, the present invention provides a mahjong tile, and the mahjong tile includes the above polymethyl methacrylate composite material or the above mahjong tile shell.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] The present invention combines specific activated shell powder with PMMA resin and toughening agent. By utilizing the porous fibrous double-helix structure of the activated shell powder, the polymethyl methacrylate composite material can easily adsorb moisture to form a water film in a high-humidity environment, thereby preventing moisture from aggregating and condensing on the surface of the polymethyl methacrylate composite material. Moreover, the activated shell powder can also adsorb small molecule additives that migrate to the surface in the polymethyl methacrylate composite material, thereby significantly improving the surface moisture absorption and stickiness of the polymethyl methacrylate composite material. The combination of the activated shell powder and the toughening agent can not only maintain the good toughening effect of the toughening agent to improve the toughness of the polymethyl methacrylate composite material, but also effectively improve the surface hardness of the polymethyl methacrylate composite material, so that the polymethyl methacrylate composite material has high wear resistance, high toughness and is not easily moisture-absorbing and sticky on the surface. Detailed implementation mode

[0026] To better illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0027] Other materials, reagents, etc. used in the examples and comparative examples can be obtained from commercial channels without special instructions.

[0028] 1. Raw materials and reagents

[0029] 1) PMMA resin

[0030] PMMA resin 1, with a melt mass flow rate of 2 g / 10 min, manufacturer Suzhou Shuangxiang, brand PMMA SX-304;

[0031] PMMA resin 2, with a melt mass flow rate of 8 g / 10 min, manufacturer Zhenjiang Qimei, brand PMMA CM-207;

[0032] PMMA resin 3, with a melt mass flow rate of 15 g / 10 min, manufacturer Sumitomo Chemical, brand PMMA LG2.

[0033] 2) Toughening agent

[0034] Toughening agent 1 (methyl methacrylate-butadiene-styrene graft copolymer), manufacturer LG Chemical, brand EM500;

[0035] Toughening agent 2 (ABS rubber powder), manufacturer South Korea Kumho, brand HR181.

[0036] 3) Activated shell powder

[0037] Activated shell powder 1, with a main component of calcium carbonate, an average particle size of 2.5 μm, and a specific surface area of 3.2 m 2 / g;

[0038] Activated oyster shell powder 2, with calcium carbonate as the main component, an average particle size of 4.5 μm, and a specific surface area of 1.4 m 2 / g;

[0039] Activated oyster shell powder 3, with calcium carbonate as the main component, an average particle size of 6.5 μm, and a specific surface area of 0.8 m 2 / g;

[0040] Activated oyster shell powders 1 - 3 are respectively obtained by calcining oyster shell powders with different average particle sizes at 400 °C in an air atmosphere for 2 h.

[0041] Activated oyster shell powder 4, with calcium carbonate as the main component, an average particle size of 2.5 μm, and a specific surface area of 3.3 m 2 / g;

[0042] Activated oyster shell powder 4 is obtained by calcining oyster shell powder with an average particle size of 2.5 μm at 500 °C in an air atmosphere for 3 h.

[0043] Activated oyster shell powder 5, with calcium carbonate as the main component, an average particle size of 2.5 μm, and a specific surface area of 3.0 m 2 / g;

[0044] Activated oyster shell powder 5 is obtained by calcining oyster shell powder with an average particle size of 2.5 μm at 300 °C in an air atmosphere for 1 h.

[0045] Activated oyster shell powder 6 is obtained by mixing and stirring activated oyster shell powder 1 and silane coupling agent (Dow Corning KH - 550, USA) at a mass ratio of 100:0.4 at 50 °C for 40 min.

[0046] Activated oyster shell powder 7, with calcium oxide as the main component, an average particle size of 2.5 μm, and a specific surface area of 10.8 m 2 / g;

[0047] Activated oyster shell powder 7 is obtained by calcining oyster shell powder with an average particle size of 2.5 μm at 1000 °C in an air atmosphere for 2 h.

[0048] Oyster shell powder, oyster shell powder with an average particle size of 2.5 μm, and a specific surface area of 2.6 m 2 / g;

[0049] The above - mentioned oyster shell powders are all purchased from Lingshou County Anda Mineral Powder Factory and obtained through crushing and screening.

[0050] Diatomite, with an average particle size of 5 μm, manufacturer: Shanghai Yuanjiang Chemical Industry, grade S16320.

[0051] 4) Functional additives

[0052] The antibacterial agent is an inorganic silver antibacterial agent, the manufacturer is Ishizuka Glass of Japan, the brand is IONPURE IPS3;

[0053] The lubricant is erucamide, the manufacturer is Sichuan Hedaxipu, the brand is ER-CH-BE MB PW;

[0054] The antioxidant is prepared by compounding a hindered phenol antioxidant (manufacturer: BASF, brand: Irganox1010) and a phosphite antioxidant (manufacturer: BASF, brand: Irgafos168) in a mass ratio of 1:1;

[0055] The weathering agent is obtained by compounding a benzotriazole ultraviolet absorber (manufacturer Tianjin Lianlong, brand name UV-329) and a hindered amine light stabilizer (manufacturer Tianjin Lianlong, brand name UV770DF) in a mass ratio of 1:1.

[0056] 2. Preparation method of polymethyl methacrylate composite material of the present invention

[0057] According to the formula, the components are mixed evenly and then added into a twin-screw extruder for melt extrusion to obtain a polymethyl methacrylate composite material; wherein the melt extrusion temperature is 220-240° C., and the screw speed of the twin-screw extruder is 300-500 rpm.

[0058] Table 1 Weight percentage of each component of the polymethyl methacrylate composite material in Examples 1 to 13

[0059] Examples 1 2 3 4 5 6 7 8 9 10 11 12 13 PMMA Resin 1 82 / / 82 82 82 82 82 82 70 94 78 88 PMMA Resin 2 / 82 / / / / / / / / / / / PMMA Resin 3 / / 82 / / / / / / / / / / Toughening Agent 1 9 9 9 / 9 9 9 9 9 15 2 12 5 Toughening Agent 2 / / / 9 / / / / / / / / / Activated Shell Powder 1 7 7 7 7 / / / / / 10 3 8 5 Activated Shell Powder 2 / / / / 7 / / / / / / / / Activated Shell Powder 3 / / / / / 7 / / / / / / / Activated Shell Powder 4 / / / / / / 7 / / / / / / Activated Shell Powder 5 / / / / / / / 7 / / / / / Activated Shell Powder 6 / / / / / / / / 7 / / / / Antibacterial Agent 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 1 0.2 0.5 0.3 Lubricant 1 1 1 1 1 1 1 1 1 2 0.5 1.5 1 Antioxidant 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 1 0.2 0.5 0.2 Weathering Agent 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 1 0.2 0.5 0.5

[0060] Table 2 Weight percentage of each component of the polymethyl methacrylate composite material in Comparative Examples 1 to 3

[0061] Comparative Example 1 2 3 PMMA Resin 1 82 82 82 Toughening Agent 1 9 9 9 Activated Shell Powder 7 7 / / Shell Powder / 7 / Diatomite / / 7 Antibacterial Agent 0.5 0.5 0.5 Lubricant 1 1 1 Antioxidant 0.5 0.5 0.5 Weathering Agent 0.5 0.5 0.5

[0062] 3. Performance testing

[0063] 1) Izod notch impact test: GB / 1843-2008 "Determination of Izod Impact Strength of Plastics" test, A-type notch.

[0064] 2) Wear resistance test: injection molding 3mm×100mm×100mm square plate, wear tester conditions: single arm load is 500g, grinding wheel model is H-18, sample rotation speed is 60r / min, rotation friction number is 5000 turns, wear resistance is evaluated by wear before and after wear (i.e. loss weight ratio), wear (%) = (mass before wear test - mass after wear test) / mass before wear test × 100%.

[0065] 3) Flexural modulus test: Tested according to GB / T 9341-2000 "Standard Test Method for Flexural Properties of Plastics".

[0066] 4) Evaluation of surface stickiness: Injection mold a square plate of 3mm×100mm×100mm, with one side being a smooth surface. Place the square plate in a constant temperature and humidity chamber at 50°C and 85% RH for 24h, then take it out and place it at room temperature for 2h. Then stack the two square plates with their smooth surfaces facing each other on the table, place a 500g weight on top, and use a thrust meter to push the upper square plate to test the maximum thrust when the square plate starts to slide. The greater the thrust, the more serious the stickiness.

[0067] Table 3 Properties of polymethyl methacrylate composites in each example and comparative example

[0068]

[0069]

[0070] According to the data in Table 3, the notched Izod impact strength of the polymethyl methacrylate composites in Examples 1 to 13 reaches 2.2 kJ / m 2 or more, and the flexural modulus reaches 2500 MPa or more. At the same time, the wear is all ≤0.17% and the maximum thrust is all ≤35 N, indicating that the polymethyl methacrylate composite material of the present invention has both high wear resistance and is not easy to absorb moisture and become sticky on the surface while maintaining high toughness. At the same time, from Examples 1 and Comparative Example 1, it can be seen that when the main component of the activated shell powder is calcium oxide, although it can also improve the surface moisture absorption of the polymethyl methacrylate composite material, it is difficult to effectively improve its wear resistance; from Examples 1 and Comparative Example 2, it can be found that replacing the activated shell powder with uncalcined shell powder not only cannot improve the surface moisture absorption and stickiness of the polymethyl methacrylate composite material, but also leads to a significant decrease in wear resistance due to an increase in the surface roughness of the polymethyl methacrylate composite material. In addition, from Examples 1 and Comparative Example 3, it can also be found that replacing the activated shell powder with porous diatomaceous earth is difficult to effectively improve the wear resistance and moisture resistance of the polymethyl methacrylate composite material.

[0071] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A polymethyl methacrylate composite material, characterized in that, By weight parts, it comprises the following components: 70-95 parts of PMMA resin, 2-15 parts of toughening agent, 3-10 parts of activated shell powder, and 1.2-6 parts of functional additive; the specific surface area of the activated shell powder ≥ 0.8m 2 / g; the functional additive includes at least one of antibacterial agent, lubricant, antioxidant, and weather resistance agent.

2. The polymethyl methacrylate composite material according to claim 1, wherein In the components of the polymethyl methacrylate composite material, the PMMA resin is 78 to 88 parts by weight, the toughening agent is 5 to 12 parts by weight, and the activated shell powder is 5 to 8 parts by weight.

3. The polymethyl methacrylate composite material according to claim 1, wherein The average particle size of the activated shell powder is 2.5 to 6.5 μm; and / or, the specific surface area of the activated shell powder is 0.8 to 3.2 m 2 / g.

4. The polymethyl methacrylate composite material according to claim 1, characterized in that, The melt mass flow rate of the PMMA resin under the conditions of 230 °C and 3.8 kg is 1 to 20 g / 10 min; and / or, the activated shell powder is obtained by calcining shell powder in an air atmosphere at 300 to 500 °C for 1 to 3 h.

5. The polymethyl methacrylate composite material according to claim 1, characterized in that, The surface of the activated shell powder is coated with a coupling agent.

6. The polymethyl methacrylate composite material according to claim 5, wherein The mass fraction of the coupling agent relative to the activated shell powder is 0.2% to 0.6%; and / or, the coupling agent includes at least one of a silane coupling agent and a titanate coupling agent.

7. The preparation method of the polymethyl methacrylate composite material according to any one of claims 1 to 6, characterized in that, It includes the following steps: mixing each component evenly and then melt-extruding to obtain the polymethyl methacrylate composite material.

8. Use of the polymethyl methacrylate composite material according to any one of claims 1 to 6 in the preparation of toys, household items, electronic components, household appliances, gardening equipment, medical technology equipment, motor vehicle parts or vehicle body parts.

9. A mahjong tile outer shell, characterized in that, The material of the mahjong tile shell includes the polymethyl methacrylate composite material according to any one of claims 1 to 6.

10. A mahjong tile, characterized in that, The mahjong tile includes the polymethyl methacrylate composite material according to any one of claims 1 to 6 or the mahjong tile shell according to claim 9.

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