Antibacterial antistatic composition and applications, antibacterial antistatic composite material and preparation method and applications thereof

Abstract

The application relates to the field of high polymer materials, and discloses an antibacterial and antistatic composition and application, an antibacterial and antistatic composite material and a preparation method and application thereof. The composition comprises a polyolefin resin, graphene oxide and carboxyl expanded microspheres; wherein, relative to 100 parts by weight of the polyolefin resin, the carboxyl expanded microspheres are 0.5-6 parts by weight, and the graphene oxide is 0.1-2 parts by weight. The composite material prepared from the composition can reduce the density while guaranteeing the mechanical properties of the material, has excellent antibacterial and antistatic properties, has good stability, and can be used for a long time.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, specifically to an antibacterial and antistatic composition and its application, an antibacterial and antistatic composite material and its preparation method and application. Background Technology

[0002] With the rapid development of the mobile intelligent electronics industry and the increasing awareness of epidemic prevention and health in society, the research on antibacterial and antistatic plastic products with "self-cleaning" functions has become a major development direction for plastic products. These products can be widely used in electronic appliance casings, household appliance components, plastic eyeglass frames and lenses, medical goggles, and other fields. Antibacterial and antistatic materials for plastics require broad-spectrum, high-efficiency, and environmentally friendly properties, good compatibility with plastic products, and the ability to effectively prevent or inhibit bacterial growth on the surface of products. Polyolefins, with their superior comprehensive properties (light weight, good mechanical properties, excellent chemical resistance, and wide process applicability), are widely used in various industries such as electronics, automobiles, and textiles. Among them, polypropylene has the widest application range. Therefore, the research on polyolefin composite materials with long-lasting antibacterial and excellent antistatic properties has great development potential.

[0003] CN112759848A discloses a method for preparing antibacterial and antistatic polypropylene using nano-silver and graphene oxide as antibacterial and antistatic pre-composite materials. The resulting antibacterial and antistatic polypropylene composite material exhibits excellent antibacterial effects, strong antistatic properties, a smooth surface without pitting or light spots, and does not affect the mechanical properties of the polypropylene composite material. However, the silver nanoparticle antibacterial agent in this method lacks long-term stability and is prone to aggregation and oxidative discoloration, thus affecting its long-term antibacterial activity.

[0004] CN111269493A discloses a method for preparing polypropylene cast films using graphene oxide / zinc oxide as antistatic agents. The method involves mixing and dispersing graphene oxide, zinc oxide, and oleic acid into a composite, which is then extruded and cast with polypropylene to obtain an antistatic polypropylene material. However, this method does not mention the antibacterial properties of the material. Furthermore, because graphene oxide, zinc oxide, and oleic acid all have poor compatibility with polypropylene, surface precipitation is likely to occur after long-term use. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of poor antibacterial and antistatic properties and inability to be used for a long time in existing polyolefin composite materials. It provides an antibacterial and antistatic composition and its application, an antibacterial and antistatic composite material and its preparation method and application. The composite material prepared by this composition reduces the density while ensuring the mechanical properties of the material. At the same time, it has excellent antibacterial and antistatic properties, good stability, and can be used for a long time.

[0006] To achieve the above objectives, the first aspect of the present invention provides an antibacterial and antistatic composition, characterized in that the composition comprises a polyolefin resin, graphene oxide, and carboxyl-expanded microspheres; wherein, relative to 100 parts by weight of the polyolefin resin, the carboxyl-expanded microspheres are 0.5-6 parts by weight, and the graphene oxide is 0.1-2 parts by weight.

[0007] A second aspect of the present invention provides an antibacterial and antistatic composite material, characterized in that the composite material is prepared from the composition described in the first aspect of the present invention.

[0008] A third aspect of the present invention provides a method for preparing an antibacterial and antistatic composite material, the method comprising: melt extruding and injection molding each component in the composition to obtain the composite material; wherein the composition is the composition described in the first aspect of the present invention.

[0009] The fourth aspect of the present invention provides an antibacterial and antistatic composite material prepared by the preparation method described in the third aspect of the present invention.

[0010] The fifth aspect of the present invention provides the application of the antibacterial and antistatic composition described in the first aspect of the present invention, and the antibacterial and antistatic composite material described in the second and fourth aspects of the present invention in antibacterial and antistatic products.

[0011] Through the above technical solutions, the antibacterial and antistatic compositions and their applications, as well as the antibacterial and antistatic composite materials and their preparation methods and applications provided by the present invention, achieve the following beneficial effects:

[0012] This invention introduces a certain amount of graphene oxide and carboxyl expanded microspheres into an antibacterial and antistatic composition. The composite material prepared by this composition reduces the density while ensuring the mechanical properties of the material. At the same time, thanks to the chemical bond formed between the carboxyl expanded microspheres and graphene oxide, the composite material has excellent antibacterial and antistatic properties, good stability, and can be used for a long time.

[0013] This invention enables chemical bonding between carboxyl-based expanded microspheres and graphene oxide through melt extrusion and injection molding, while maintaining the expanded microspheres in a foamed state. This helps to reduce density while ensuring the mechanical properties of the material, and also achieves good antibacterial and antistatic effects.

[0014] The antibacterial and antistatic compositions and composite materials of the present invention have broad application prospects in antibacterial and antistatic products. Attached Figure Description

[0015] Figure 1 This is a SEM image of the antibacterial and antistatic composite material prepared in Example 1 with a scale of 20 μm;

[0016] Figure 2 This is a SEM image of the antibacterial and antistatic composite material prepared in Example 1 with a scale of 200 μm. Detailed Implementation

[0017] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0018] The first aspect of the present invention provides an antibacterial and antistatic composition, characterized in that the composition comprises a polyolefin resin, graphene oxide and carboxyl-expanded microspheres; wherein, relative to 100 parts by weight of the polyolefin resin, the carboxyl-expanded microspheres are 0.5-6 parts by weight and the graphene oxide is 0.1-2 parts by weight.

[0019] This invention introduces a certain amount of graphene oxide and carboxyl expanded microspheres into an antibacterial and antistatic composition. The composite material prepared by this composition reduces the density while ensuring the mechanical properties of the material. At the same time, thanks to the chemical bond formed between the carboxyl expanded microspheres and graphene oxide, the composite material has excellent antibacterial and antistatic properties, good stability, and can be used for a long time. The following is a detailed description.

[0020] On the one hand, the present invention introduces carboxyl-expanded microspheres into the antibacterial and antistatic composition. These microspheres can expand into larger-diameter closed-cell polymer microspheres at high temperatures and are uniformly dispersed in the polymer melt, thereby effectively reducing the density of the composite material made from the composition while ensuring mechanical properties.

[0021] On the other hand, the expanded microspheres used in this invention have undergone surface chemical modification, and the surface of the microspheres contains abundant carboxyl groups, which can chemically bond with the hydroxyl groups on the surface of graphene oxide. This allows most of the graphene to adhere to the surface of the microspheres. After the microspheres are foamed, the graphene oxide will be enriched as much as possible in the gaps between the closed-cell microspheres, which is conducive to the formation of a three-dimensional network structure by the overlapping of the sheet structures of graphene oxide at a low content, thereby achieving excellent antistatic effect.

[0022] On the other hand, thanks to the chemical bond formed between the carboxyl expanded microspheres and graphene oxide, as well as the good bonding force with the matrix resin, the composite material made from this composition resists long-term damp heat aging without graphene precipitation, thereby improving the long-term antibacterial effect.

[0023] According to the present invention, in order to further optimize the performance of the composite material prepared from the composition, the composition comprises, relative to 100 parts by weight of polyolefin resin, 1-3 parts by weight of carboxyl expanded microspheres and 0.2-0.5 parts by weight of graphene oxide.

[0024] According to the present invention, the content of carboxyl groups in the carboxyl-expanded microspheres is 0.1-10 mmol / kg. When the above range is met, it is beneficial to increase the chemical bonding with graphene oxide, thereby improving the interfacial compatibility between the two and achieving excellent antibacterial and antistatic properties; more preferably, it is 1-3 mmol / kg.

[0025] According to the present invention, the initial particle size (particle size before expansion) of the carboxyl expandable microspheres is 1-100 μm. When the particle size of the carboxyl expandable microspheres meets the above range, effective thermal expansion can be achieved. When it is preferably 5-35 μm, it is beneficial to further improve the thermal expansion ratio.

[0026] According to the present invention, the carboxyl-based expanded microspheres have a core-shell structure, with a polymer of the general formula shown in Formula I as the shell and an alkane-based foaming agent as the core;

[0027]

[0028] Wherein, P is a polymer, and R1 and R2 are each independently H or CH3;

[0029] According to the present invention, R1 and R2 are H.

[0030] According to the present invention, the foaming temperature of the carboxyl expanded microspheres is ≥200℃, preferably 200-220℃;

[0031] According to the present invention, the alkane blowing agent is selected from at least one of isooctane, n-hexane, and heptane.

[0032] According to the present invention, the graphene oxide sheets have a diameter of 0.2-10 μm and a peelability of ≥95%. When the sheet diameter and peelability meet the above ranges, it is beneficial for the dispersion of the graphene oxide in the composition, thereby facilitating the formation of a three-dimensional network structure by the overlapping of the graphene sheets between the carboxyl-expanded microspheres, thus improving the antibacterial and antistatic properties. Preferably, when the graphene oxide sheet diameter is 2-5 μm and the peelability is ≥98%, it is further beneficial for the formation of the three-dimensional network structure.

[0033] According to the present invention, the carbon content of the graphene oxide is 60-90 wt%, and the oxygen content is 5-38 wt%. When the above range is met, the graphene oxide exhibits good interfacial compatibility with other components. Preferably, when the carbon content is 75-85 wt% and the oxygen content is 13-20 wt%, it is beneficial to further improve the interfacial compatibility with other components.

[0034] According to the present invention, the polyolefin resin is selected from polyethylene resin and / or polypropylene resin. The present invention does not particularly limit the type of polyethylene resin and polypropylene resin; for example, polypropylene resin is commercially available and has a density of 0.91-0.95 g / cm³. 3 The melt flow index at 215℃ and 2.16kg load is 35-45g / 10min.

[0035] According to the present invention, the composition further includes a compatibilizer for enhancing the interfacial bonding effect between the polyolefin resin and the filler, thereby optimizing the material properties.

[0036] According to the present invention, the compatibilizer is 0.1-5 parts by weight, preferably 0.2-3 parts by weight, relative to 100 parts by weight of polyolefin resin.

[0037] According to the present invention, the compatibilizer is a maleic anhydride graft copolymer. Preferably, the maleic anhydride graft copolymer is selected from maleic anhydride-grafted POE and / or maleic anhydride-grafted polyethylene. The present invention does not particularly limit the type of maleic anhydride-grafted POE and maleic anhydride-grafted polyethylene. For example, maleic anhydride-grafted POE and maleic anhydride-grafted polyethylene are commercially available, wherein the maleic anhydride grafting rate in the maleic anhydride-grafted POE is 1-1.4% by weight, and the maleic anhydride grafting rate in the maleic anhydride-grafted polyethylene is 0.6-1% by weight.

[0038] According to the present invention, the composition further includes a lubricant for accelerating the uniform dispersion of various materials, which automatically evaporates in the later stages of processing without affecting the material properties.

[0039] According to the present invention, the amount of the lubricant is 0.1-5 parts by weight, preferably 0.5-2 parts by weight, relative to 100 parts by weight of polyolefin resin.

[0040] According to the present invention, the lubricant is selected from at least one of white oil, paraffin wax and polyethylene wax.

[0041] The present invention provides an exemplary method for preparing the carboxyl expanded microspheres, comprising: contacting the expanded microspheres with a maleic anhydride compound and performing an amidation reaction in the presence of a solvent to obtain carboxyl expanded microspheres;

[0042] The expanded microspheres have a core-shell structure, with a polymer of the general formula shown in Formula II as the shell and an alkane-based foaming agent as the core.

[0043] P-NH2 type II;

[0044] Wherein, P is a polymer;

[0045] The maleic anhydride compounds have the structure shown in Formula III:

[0046]

[0047] R1 and R2 are each independently H or CH3.

[0048] In this invention, when the polymer shell of the expanded microsphere has the general formula shown in Formula II and the maleic anhydride compound has the structure shown in Formula III, the two can undergo an amidation reaction to obtain a polymer having the general formula shown in Formula I, thereby making the surface of the expanded microsphere contain abundant carboxyl groups, increasing the interfacial compatibility with graphene oxide.

[0049] According to the present invention, when both R1 and R2 are H, it is advantageous for maleic anhydride compounds to undergo an amidation reaction with the primary amine of the polymer shown in Formula II.

[0050] According to the present invention, the content of -NH2 in the expanded microspheres is 0.1-10 mmol / kg. When the above range is met, it is beneficial to carry out a sufficient amidation reaction with maleic anhydride compounds, thereby increasing the content of carboxyl groups on the surface of the expanded microspheres and increasing the interfacial compatibility with graphene oxide. When the content of -NH2 in the expanded microspheres is preferably 1-3 mmol / kg, the interfacial compatibility between the carboxyl expanded microspheres and graphene oxide can be further improved.

[0051] According to the present invention, the foaming temperature of the expanded microspheres is ≥200℃, preferably 200-220℃.

[0052] According to the present invention, the alkane blowing agent is selected from at least one of isooctane, n-hexane, and heptane.

[0053] The present invention does not particularly limit the type of polymer of Formula II. For example, the polymer of Formula II is selected from copolymers of at least one acrylamide monomer and other olefin monomers, wherein the acrylamide monomer is selected from acrylamide and / or methacrylamide, and the other olefin monomer is selected from at least one of acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, methyl acrylate and methyl methacrylate.

[0054] The present invention provides examples of expanded microspheres, such as Expansionl 1093DU120, 909DU80, 920DU40, 920DU80, 920DU120, and 950DU80 from Akzo Nobel, Sweden; F190D, F230D, and F260D from Nippon Ink Chemical; DU190L and DU230L from Shanghai Xineng; and 4600X from Dongjin, South Korea.

[0055] According to the present invention, the mass ratio of the expanded microspheres to the maleic anhydride compound is 1:0.05-1. When the above range is met, it is beneficial for the two to react. When the ratio is preferably 1:0.1-0.3, it is beneficial to increase the content of carboxyl groups on the surface of the expanded microspheres.

[0056] According to the present invention, the conditions for the amidation reaction include: a reaction temperature of 0-50°C and a reaction time of 1-12 h. When the above ranges are met, it is beneficial for the expanded microspheres and the maleic anhydride compounds to react. When the reaction temperature is preferably 30-50°C and the reaction time is preferably 3-6 h, it is beneficial to obtain expanded microspheres with high carboxyl content.

[0057] In one specific embodiment of the present invention, the reaction temperature is 30°C and the reaction time is 3-6 hours.

[0058] The present invention does not particularly limit the type of solvent, as long as it can dissolve maleic anhydride compounds, for example, benzene.

[0059] The present invention does not particularly limit the content of solvent; for example, the mass ratio of solvent to maleic anhydride compound is 1:0.01-0.07.

[0060] A second aspect of the present invention provides an antibacterial and antistatic composite material, characterized in that the composite material is prepared from the composition described in the present invention.

[0061] A third aspect of the present invention provides a method for preparing an antibacterial and antistatic composite material, characterized in that the preparation method includes: melting and extruding each component of the antibacterial and antistatic composition of the present invention and injection molding to obtain the composite material.

[0062] This invention uses melt extrusion and injection molding to chemically bond carboxyl-coated expanded microspheres with graphene oxide, keeping the expanded microspheres in a foamed state. This helps to reduce density while maintaining the mechanical properties of the material, and also achieves good antibacterial and antistatic effects.

[0063] In this invention, although the components are thoroughly mixed and chemical bonds form between the carboxyl-coated expanded microspheres and graphene oxide during melt extrusion, the microspheres in the extruded material remain in an unfoamed state. Subsequently, injection molding is used to obtain a foamed, lightweight antibacterial and antistatic composite material. After molding, the material is rapidly cooled and solidified in a mold, maintaining the expanded microspheres in a foamed state. After foaming, graphene is enriched in the gaps between the foamed microspheres, facilitating the formation of a three-dimensional network structure with low graphene content, thus achieving excellent antistatic effects. Simultaneously, the injection molding process improves the bonding force between graphene oxide and other additives and the matrix resin, enabling the composite material to resist long-term humid heat aging without the precipitation of graphene and other additives, thereby enhancing its long-term antibacterial effect.

[0064] According to the present invention, the conditions for melt extrusion include: a melt extrusion temperature of 150-180°C and a rotation speed of 50-100 r / min. When the above conditions are met, the components can be fully mixed, and at the same time, a chemical bond is formed between the carboxyl expanded microspheres and the graphene oxide, so that the graphene adheres to the surface of the microspheres.

[0065] According to the present invention, the temperature of the melt extrusion is controlled in multiple stages, preferably three stages. The temperature of the first stage (rear part of the extruder barrel) is 150℃-160℃, the temperature of the second stage (middle part of the extruder barrel) is 160℃-170℃, the temperature of the third stage (front part of the extruder barrel) is 170℃-175℃, the die head temperature is 175-180℃, and the screw speed is 50-100 r / min. These melt extrusion conditions are beneficial for further improving the uniformity of mixing among the components and the full formation of chemical bonds between the carboxyl expanded microspheres and graphene oxide.

[0066] According to the present invention, the injection molding conditions include: the molding temperature is controlled in multiple stages, preferably three stages, wherein the temperature of the first stage (rear part of the injection molding machine barrel) is 160℃-190℃, the temperature of the second stage (middle part of the injection molding machine barrel) is 195℃-215℃, and the temperature of the third stage (front part of the injection molding machine barrel) is 215℃-230℃; the nozzle temperature is 170℃-185℃, the molding pressure (injection pressure) is 10-50 bar, and the injection molding speed (injection rate) is 1-50 cm. 3 / s, and the cooling temperature (mold temperature) after molding is 20-120℃. When the above range is met, it is beneficial to obtain a foamed, lightweight antibacterial and antistatic composite material, and the rapid cooling and shaping in the mold after molding keeps the expanded microspheres in a foamed state.

[0067] The present invention provides an exemplary process for preparing the composite material, comprising:

[0068] S1. The antibacterial and antistatic composition is mixed evenly and then melt-extruded through a twin-screw extruder. After traction, cooling, pelletizing and drying, modified granules are obtained.

[0069] S2. The modified particles are injection molded using an injection molding machine to obtain the composite material.

[0070] In step S1, the temperature of the rear part of the extruder barrel is 150℃-160℃, the temperature of the middle part is 160℃-170℃, the temperature of the front part is 170℃-175℃, the screw speed is 50-100r / min, and the die head temperature is 175-180℃.

[0071] In step S2, the temperature of the injection molding machine barrel is 160℃-190℃ at the rear, 195℃-215℃ at the middle, and 215℃-230℃ at the front; the nozzle temperature is 170℃-185℃; the mold temperature is 20℃-90℃; the injection pressure is 10-50 bar; and the injection speed is 5-20 cm / s. 3 / s.

[0072] The fourth aspect of the present invention provides an antibacterial and antistatic composite material prepared by the preparation method described in the present invention.

[0073] The fifth aspect of the present invention provides an application of the antibacterial and antistatic composition and the antibacterial and antistatic composite material of the present invention in antibacterial and antistatic products.

[0074] The present invention will be described in detail below through embodiments.

[0075] The test methods and standards for each performance parameter in the following examples and comparative examples are as follows:

[0076] (1) Mechanical properties: relative density was measured according to standard GB / T 1033.1-2008, tensile strength was tested according to standard ISO 527-1 / -2, flexural strength was tested according to standard ISO 178, and impact strength of simply supported beam was tested according to standard ISO 179 / 1eA.

[0077] (2) Antistatic properties: The antistatic properties of the material are evaluated by testing the surface resistivity and volume resistivity of the sample. The test standard is IEC 60093.

[0078] (3) Antibacterial properties: Refer to QB / T 2591-2003A "Test methods and antibacterial effects of antibacterial plastics", and use Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 for testing.

[0079] (4) Melt index: Determined according to standard GB / T 3682-2000.

[0080] (5) Group content: The group content of the sample was tested by acid-base titration. The content of amine groups was titrated with hydrochloric acid, and the content of carboxyl groups was titrated with sodium hydroxide.

[0081] In the following embodiments and comparative examples, the sources of equipment and raw materials are as follows:

[0082] Twin-screw extruder: purchased from Coperon (Nanjing) Machinery Co., Ltd., model 35#;

[0083] Injection molding machine: Purchased from Haitian Group, model 120T;

[0084] Polyolefin resin: Grade RF365MO (purchased from Borealis, standard grade polypropylene, density 0.98 g / cm³) 3 The melt index at 215℃ and 2.16kg is 40g / 10min.

[0085] Expanded microspheres: F230D (purchased from Japan Ink Chemicals, -NH2 content 2.2 mmol / kg), 4600X (purchased from Korea Dongjin Corporation, -NH2 content 0.2 mmol / kg).

[0086] Graphene oxide (model SE1440, purchased from Changzhou Sixth Element Co., Ltd., with a peelability of ≥95%; carbon content of 80wt% and oxygen content of 15wt%), with sheet diameter of 2-5μm.

[0087] Compatibilizers: maleic anhydride-grafted POE (model 8402, purchased from Dow Chemical, USA, maleic anhydride grafting rate 1.2 wt%), maleic anhydride-grafted polyethylene (model TY1353, purchased from Dow Chemical, USA, maleic anhydride grafting rate 0.8 wt%).

[0088] Other raw materials are commercially available conventional products.

[0089] I. Preparation of Carboxyl Expanded Microspheres

[0090] Preliminary Example 1

[0091] Maleic anhydride (C4H2O3) was dissolved in benzene to obtain a mixed solution. Expanded microspheres F230D were added to the mixed solution, wherein the mass ratio of expanded microspheres to maleic anhydride was 1:0.25 and the mass ratio of benzene to maleic anhydride was 1:0.05. The reaction was carried out at 30°C for 6 hours. After filtration, washing with acetone, and drying, carboxyl expanded microspheres F230D-1 were obtained. Specific characteristics are detailed in Table 2.

[0092] Preliminary Example 2-5

[0093] Carboxyl-based expanded microspheres were prepared according to the method of Preliminary Example 1, except that the mass ratio of expanded microspheres to maleic anhydride, the reaction temperature, and the reaction time were different from those in Preliminary Example 1. The reaction conditions are detailed in Table 1. Carboxyl-based expanded microspheres F230D-2, F230D-3, F230D-4, and F230D-5 were obtained respectively. Their specific characteristics are detailed in Table 1.

[0094] Preliminary Example 6

[0095] Carboxyl-infused expanded microspheres were prepared according to the method of Preliminary Example 1, except that the expanded microspheres were replaced with 4600X. The reaction conditions are detailed in Table 1, and carboxyl-infused expanded microspheres 4600X-1 were obtained. The specific characteristics are detailed in Table 2.

[0096] Table 1

[0097] serial number Carboxyl-infused expanded microspheres Expanded microspheres : maleic anhydride : (mass ratio) Reaction temperature / ℃ Reaction time / h Preliminary Example 1 F230D-1 1:0.25 30 6 Preliminary Example 2 F230D-2 1:0.15 30 5 Preliminary Example 3 F230D-3 1:0.075 30 4 Preliminary Example 4 F230D-4 1:1 30 3 Preliminary Example 5 F230D-5 1:0.05 30 8 Preliminary Example 6 4600X-1 1:0.25 30 6

[0098] Table 2

[0099] model Starting particle size / μm Carboxyl content mmol / kg Foaming temperature / ℃ Foaming agent type F230D-1 25 2.1 210 Isooctane F230D-2 25 1.1 210 Isooctane F230D-3 25 0.3 210 Isooctane F230D-4 25 9.2 210 Isooctane F230D-5 25 0.05 210 Isooctane 4600X 35 0.11 190 n-Hexane

[0100] II. Preparation of Antibacterial and Antistatic Compositions

[0101] Preparation Example 1

[0102] Polypropylene resin, graphene oxide, carboxyl expanded microspheres F230D-1, maleic anhydride-grafted POE, and white oil were mixed evenly to obtain an antibacterial and antistatic composition S1. The specific proportions of each component are detailed in Table 3.

[0103] Preparation Examples 2-5

[0104] Antibacterial and antistatic compositions were prepared according to the method of Preparation Example 1, except that the proportions of each component in the composition were different from those in Preparation Example 1, resulting in antibacterial and antistatic compositions S2-S5, as shown in Table 3.

[0105] Preparation Examples 6-10

[0106] Antibacterial and antistatic compositions were prepared according to the method of Preparation Example 1, except that the type of carboxyl-expanded microspheres in the compositions was different from that in Preparation Example 1, resulting in antibacterial and antistatic compositions S6-S10, as shown in Table 3.

[0107] Preparation Example 11

[0108] The antibacterial and antistatic composition was prepared according to the method of Preparation Example 1, except that maleic anhydride grafted POE and white oil were not added, resulting in antibacterial and antistatic composition S11, as shown in Table 3.

[0109] Comparative Preparation Examples 1-2

[0110] Antibacterial and antistatic compositions were prepared according to the method of Preparation Example 1, except that the amounts of graphene oxide 1 and carboxyl expanded microspheres F230D-1 used in Preparation Examples 1-2 were different from those in Preparation Example 1, as detailed in Table 3, resulting in antibacterial and antistatic compositions D1-D2.

[0111] Comparative preparation example 3

[0112] The antibacterial and antistatic composition was prepared according to the method of Preparation Example 1, except that carboxyl-expanded microspheres F230D-1 were not added, resulting in antibacterial and antistatic composition D3.

[0113] Comparative preparation example 4

[0114] An antibacterial and antistatic composition was prepared according to the method of Preparation Example 1, except that expanded microspheres F230D were used instead of the carboxyl expanded microspheres F230D-1 in Preparation Example 1, resulting in an antibacterial and antistatic composition D4.

[0115] Table 3

[0116]

[0117]

[0118] In the table above, the amounts of each component are relative to 100 parts by weight of polyolefin resin.

[0119] III. Preparation of Antibacterial and Antistatic Composite Materials

[0120] Example 1

[0121] Step 1: The composition S1 is melt-extruded through a twin-screw extruder, followed by traction, cooling, pelletizing, and drying to obtain modified granules; wherein, the temperature at the rear of the extruder barrel is 155℃ and the screw speed is 75 r / min; the temperature in the middle of the barrel is 165℃ and the screw speed is 75 r / min; the temperature at the front of the barrel is 175℃ and the screw speed is 75 r / min; the die head temperature is 180℃; the drying temperature is 105℃; and the drying time is 6 h.

[0122] Step 2: Inject the modified granules into an antibacterial and antistatic composite material T1. The temperatures at the rear of the injection molding machine barrel are 180°C, the middle of the barrel is 210°C, the front of the barrel is 220°C, the nozzle temperature is 175°C, the mold temperature is 80°C, the injection pressure is 20 bar, and the injection speed is 15 cm / s. 3 The properties of the antibacterial and antistatic composite material are shown in Tables 4 and 5.

[0123] Example 2-11

[0124] The antibacterial and antistatic composite material was prepared according to the method in Example 1, except that compositions S2-S11 were added to obtain antibacterial and antistatic composite materials T2-T11. The properties of the above antibacterial and antistatic composite materials are shown in Tables 4 and 5.

[0125] Comparative Examples 1-4

[0126] The antibacterial and antistatic composite material was prepared according to the method of Example 1, except that compositions D1-D4 were added respectively to obtain antibacterial and antistatic composite materials W1-W4. The properties of the above antibacterial and antistatic composite materials are shown in Tables 4 and 5.

[0127] Table 4

[0128]

[0129] Among them, surface resistivity 1 and volume resistivity 1 represent the test values ​​of the sample after being treated under the double 85 conditions (85℃, 85% relative humidity) for 1000h.

[0130] Table 5

[0131]

[0132]

[0133] The antibacterial rates at 24h and 48h were measured under standard conditions, while the antibacterial rate after 1000h was measured under double 85 conditions (85℃, 85% relative humidity).

[0134] Figure 1 and Figure 2 The image shows the SEM image of the composite material prepared in Example 1. The diameter of the microspheres after injection molding expands by 3-5 times and the volume increases by 30-120 times. On the one hand, this achieves the lightweighting of the composite material, and on the other hand, it fills most of the volume of the composite material, which significantly reduces the space for the arrangement of graphene oxide.

[0135] As can be seen from the test results in Tables 4 and 5, compared with Example 11, the antistatic properties and antibacterial properties under long-term damp heat aging of Example 1 were significantly improved. This may be attributed to the fact that the 4600X-1 expanded microspheres have a low amino content on their surface, fewer sites for chemical reaction with maleic anhydride, and thus a low carboxyl content, resulting in a lower chemical bonding effect with graphene oxide than in Example 1.

[0136] Compared with Comparative Examples 1-2, Example 1 has the advantage that the carboxyl-expanded microspheres can form abundant chemical bonding sites with graphene oxide, thereby reducing the density while ensuring the mechanical properties of the material, and also exhibiting excellent antibacterial and antistatic properties.

[0137] Compared to Comparative Example 3, Example 1 showed no significant decrease in mechanical properties (especially notched impact strength and flexural strength) despite the reduced density. Simultaneously, the antistatic properties and antibacterial properties under long-term damp-heat aging of the composite material were significantly improved. This is because Example 1 introduced carboxyl-coated expanded microspheres during the preparation of the antibacterial and antistatic composite material. These microspheres can self-expand at high temperatures into larger-diameter closed-cell polymer microspheres, uniformly dispersed in the polymer melt, effectively reducing the density of the composite material while maintaining its mechanical properties. Furthermore, the introduction of carboxyl-coated expanded microspheres allows for chemical bonding with graphene oxide, greatly improving their interfacial compatibility. The nanosheet-structured graphene oxide in the polypropylene melt is more easily exfoliated and dispersed, tending to accumulate in the interstitial spaces of the expanded microspheres, and more easily and effectively assembling into a three-dimensional network structure, thus significantly enhancing the antistatic effect of the polypropylene composite material. In addition, due to the chemical bond formed between the carboxyl expanded microspheres and graphene oxide, as well as the good bonding force with the matrix resin, the antibacterial and antistatic composite material can resist long-term damp heat aging without graphene precipitation, thereby improving its long-term antibacterial effect.

[0138] Compared with Comparative Example 4, the antistatic properties and antibacterial properties under long-term damp heat aging of Example 1 were significantly improved, for the same reasons as the comparison with Comparative Example 3 above.

[0139] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. An antibacterial and antistatic composition, characterized in that, The composition comprises a polyolefin resin, graphene oxide, and carboxyl-expanded microspheres; Of which, relative to 100 parts by weight of polyolefin resin, the carboxyl expanded microspheres are 0.5-6 parts by weight and the graphene oxide is 0.1-2 parts by weight; The carboxyl-expanded microspheres have a core-shell structure, with a polymer of the general formula shown in Formula I as the shell and an alkane-based foaming agent as the core. Equation I; In this system, R1 and R2 are each independently H or CH3, and P is a polymer.

2. The composition according to claim 1, characterized in that, The carboxyl-expanded microspheres are 1-3 parts by weight relative to 100 parts by weight of polyolefin resin, and the graphene oxide is 0.2-0.5 parts by weight.

3. The composition according to claim 1 or 2, characterized in that, The carboxyl-infused expanded microspheres contain 0.1-10 mmol / kg of carboxyl groups. And / or, the initial particle size of the carboxyl-expanded microspheres is 1-100 μm; And / or, R1 and R2 are H; And / or, the foaming temperature of the carboxyl expanded microspheres is ≥200℃; And / or, the alkane blowing agent is selected from at least one of isooctane, n-hexane, and heptane.

4. The composition according to claim 3, characterized in that, The carboxyl-infused expanded microspheres contain 1-3 mmol / kg of carboxyl groups. And / or, the initial particle size of the carboxyl-expanded microspheres is 5-35 μm; And / or, the foaming temperature of the carboxyl expanded microspheres is 200-220℃.

5. The composition according to claim 1, characterized in that, The graphene oxide sheets have a diameter of 0.2-10 μm and a peelability of ≥95%. And / or, the carbon content of the graphene oxide is 60-90 wt%, and the oxygen content is 5-38 wt%.

6. The composition according to claim 5, characterized in that, The graphene oxide sheets have a diameter of 2-5 μm and a peelability of ≥98%. And / or, the carbon content of the graphene oxide is 75-85 wt%, and the oxygen content is 13-20 wt%.

7. The composition according to claim 1, characterized in that, The polyolefin resin is selected from polyethylene resin and / or polypropylene resin.

8. The composition according to claim 1, characterized in that, The composition also includes a compatibilizer.

9. The composition according to claim 8, characterized in that, The compatibilizer is 0.1-5 parts by weight relative to 100 parts by weight of polyolefin resin; And / or, the compatibilizer is a maleic anhydride graft copolymer.

10. The composition according to claim 9, characterized in that, The compatibilizer is 0.2-3 parts by weight relative to 100 parts by weight of polyolefin resin; And / or, the maleic anhydride graft copolymer is selected from maleic anhydride grafted POE and / or maleic anhydride grafted polyethylene.

11. The composition according to claim 1, characterized in that, The composition also includes a lubricant.

12. The composition according to claim 11, characterized in that, The amount of the lubricant used is 0.1-5 parts by weight relative to 100 parts by weight of polyolefin resin; And / or, the lubricant is selected from at least one of white oil, paraffin wax and polyethylene wax.

13. The composition according to claim 12, characterized in that, The amount of the lubricant used is 0.5-2 parts by weight relative to 100 parts by weight of polyolefin resin.

14. The composition according to claim 1, characterized in that, The preparation method of the carboxyl-coated expanded microspheres includes: In the presence of a solvent, expanded microspheres are contacted with maleic anhydride compounds and subjected to an amidation reaction to obtain carboxyl expanded microspheres; The expanded microspheres have a core-shell structure, with a polymer of the general formula shown in Formula II as the shell and an alkane-based foaming agent as the core. P-NH2 type II; Wherein, P is a polymer; The maleic anhydride compounds have the structure shown in Formula III: Formula III; R1 and R2 are each independently H or CH3.

15. The composition according to claim 14, characterized in that, R1 and R2 are H; And / or, the -NH2 content in the expanded microspheres is 0.1-10 mmol / kg; And / or, the mass ratio of the expanded microspheres to the maleic anhydride compound is 1:0.05-1; And / or, the conditions for the amidation reaction include: a reaction temperature of 0-50°C; The reaction time is 1-12 hours.

16. The composition according to claim 15, characterized in that, The -NH2 content in the expanded microspheres is 1-3 mmol / kg; And / or, the mass ratio of the expanded microspheres to the maleic anhydride compound is 1:0.1-0.

3.

17. An antibacterial and antistatic composite material, characterized in that, The composite material is prepared from the composition according to any one of claims 1-16.

18. A method for preparing an antibacterial and antistatic composite material, characterized in that, The preparation method includes: melting and extruding the components in the composition and injection molding to obtain the composite material; Wherein, the composition is the antibacterial and antistatic composition according to any one of claims 1-16.

19. The preparation method according to claim 18, characterized in that, The conditions for melt extrusion include: melt extrusion temperature of 150℃-180℃ and rotation speed of 50-100 r / min.

20. The preparation method according to claim 18 or 19, characterized in that, The injection molding conditions include: multi-stage temperature control, molding pressure of 10-50 bar, and injection speed of 1-50 cm. 3 / s, and the cooling temperature after molding is 20-120℃.

21. The preparation method according to claim 20, characterized in that, The injection molding conditions include: the molding temperature is controlled in three stages, wherein the first stage temperature is 160℃-190℃, the second stage temperature is 195℃-215℃, and the third stage temperature is 215℃-230℃.

22. An antibacterial and antistatic composite material prepared by the preparation method according to any one of claims 18-21.

23. The use of an antibacterial and antistatic composition according to any one of claims 1-16, or an antibacterial and antistatic composite material according to claim 17 or 22, in antibacterial and antistatic articles.

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