Antibacterial and mildew-proof PP plastic and preparation method thereof

Abstract

The invention belongs to the technical field of plastics, and particularly relates to an antibacterial and mildew-proof PP plastic and a preparation method thereof. The polypropylene composite material comprises the following components in parts by weight: 100 parts of polypropylene resin; 4-8 parts of a dispersant; 2-4 parts of a plasticizer; 1-2 parts of an antioxidant; 2 to 6 parts of Co-TCPP-curcumin MOFs (metal organic frameworks); and 3 to 7 parts of CTAB modified zinc-aluminum hydrotalcite. According to the invention, the cobalt-based metal organic framework containing curcumin is prepared to promote the improvement of the antibacterial and mildew-proof properties of the PP plastic, and the zinc-aluminum hydrotalcite is modified by CTAB, so that not only is the dispersity of the magnesium-aluminum hydrotalcite improved, but also the improvement of the antibacterial property is promoted. The prepared PP plastic is excellent in performance and good in prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of plastics, and more specifically, relates to an antibacterial and mildew-proof PP plastic and a preparation method thereof. Background Art

[0002] Polypropylene has the advantages of low cost, low density, easy processing, good chemical resistance, and excellent mechanical properties. It is the most commonly used thermoplastic polymer in daily life. In recent years, people's requirements for the antibacterial properties of materials have gradually increased. The hydrophobicity and inertness of the polypropylene surface often lead to bacterial contamination, hindering its potential application in the antibacterial field. The introduction of substances with antibacterial activity to achieve antibacterial effects has received widespread attention in the fields of polymer materials and medical and health care. The preparation of antibacterial polypropylene materials has become a hot topic in the research of antibacterial plastics.

[0003] CN118165420A discloses a preparation process of wear-resistant antibacterial PP plastics. GMA grafted polypropylene is used as a compatibilizer to bond with hydroxyl, carboxyl and other groups of acetylcysteine-based polymer antibacterial agent, so that the antibacterial agent is evenly distributed in the polypropylene matrix. The acetylcysteine-based polymer antibacterial agent has good heat resistance and structural stability. When it is melt-blended with polypropylene at high temperature, high-temperature thermal decomposition will not occur, thereby ensuring the antibacterial effect of the antibacterial agent. Adding GMA grafted polypropylene as a compatibilizer promotes the uniform dispersion of oxidized carbon fibers in the polypropylene matrix. At the same time, the acetylcysteine-based polymer with a hyperbranched structure is mutually entangled with the polypropylene molecular chain to form a physical cross-linking effect. Under the synergistic effect, the mass wear and friction coefficient of the PP plastic are reduced, and the wear resistance is improved.

[0004] CN118165458A discloses a high-strength antibacterial PP plastic and a preparation method thereof, wherein acrylate sulfonate isothiazolinone is used for melting to obtain isothiazolinone grafted polypropylene, thereby achieving grafting of isothiazolinone and sulfonate structures in polypropylene. CTAB-modified diatomaceous earth is used as a filler and is compounded with polyethylene wax isothiazolinone grafted polypropylene to obtain a high-strength antibacterial PP plastic. Polypropylene is grafted with an antibacterial isothiazolinone structure, which can interact with bacterial cell wall membranes and intracellular enzymes, destroying cell reproduction and metabolism, thereby killing or inhibiting the growth and reproduction of microorganisms, and having a resistance effect on bacteria, thereby improving the antibacterial properties of PP plastics. At the same time, the added diatomaceous earth can effectively improve the hardness and strength of PP plastics.

[0005] CN118063883A discloses a wear-resistant and antibacterial PP plastic, which comprises the following raw materials: polypropylene, ethylene acrylic acid copolymer, dibutyl phthalate, talcum powder, antioxidant, polypropylene wax, modified SEBS quaternary ammonium salt antibacterial agent, and nano-titanium dioxide composite wear-resistant particles; by grafting terminal hydroxyl polybutadiene onto the surface of nano-titanium dioxide, the wear resistance and mechanical properties of the PP plastic are improved, and the various raw materials each have their own strengths, give full play to and utilize their own characteristics, thereby further broadening the scope of application of the wear-resistant and antibacterial PP plastic.

[0006] CN115109342A discloses polypropylene plastic and its preparation method. The polypropylene plastic comprises, by weight, 85 to 94 parts of polypropylene resin, 1 to 5 parts of antibacterial agent and 5 to 10 parts of PDMS surface-modified diatomaceous earth. The polypropylene plastic is modified by adding an antibacterial agent and using polydimethylsiloxane (PDMS) surface-modified diatomaceous earth for blending, thereby reducing the surface tension of the polypropylene plastic, and the modified polypropylene plastic has excellent antibacterial and mildew-proof effects.

[0007] In the prior art, the antibacterial property can be improved by adding an antibacterial agent, but other substances need to be added to improve the mechanical properties at the same time. The present invention can improve not only the antibacterial property but also the mechanical properties by making a self-made antibacterial component. Summary of the invention

[0008] The technical problem to be solved by the present invention is to overcome the defects and deficiencies in the prior art, and to provide an antibacterial and mildew-proof PP plastic and a preparation method thereof. In parts by weight, the following components are included: 100 parts of polypropylene resin; 4 to 8 parts of dispersant; 2 to 4 parts of plasticizer; 1 to 2 parts of antioxidant; 2 to 6 parts of Co-TCPP-curcumin MOFs; 3 to 7 parts of CTAB-modified zinc-aluminum hydrotalcite. The present invention promotes the improvement of the antibacterial and mildew-proof properties of PP plastic by preparing a cobalt-based metal organic framework containing curcumin, and by modifying the zinc-aluminum hydrotalcite with CTAB, not only the dispersibility of the magnesium-aluminum hydrotalcite is improved, but also the improvement of the antibacterial properties is promoted. The PP plastic prepared by the present invention has excellent performance and good prospects.

[0009] The purpose of the invention is to provide an antibacterial and mildew-proof PP plastic.

[0010] Another object of the present invention is to provide a method for preparing antibacterial and mildew-proof PP plastic.

[0011] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0012] An antibacterial and mildew-proof PP plastic, comprising the following components in parts by weight:

[0013] 100 parts of polypropylene resin;

[0014] 4 to 8 parts of dispersant;

[0015] 2 to 4 parts of plasticizer;

[0016] 1-2 parts of antioxidant;

[0017] Co-TCPP-curcumin MOFs 2 to 6 parts;

[0018] 3 to 7 parts of CTAB-modified zinc-aluminum hydrotalcite.

[0019] In the present invention, the preferred technical scheme, the preparation method of Co-TCPP-curcumin MOFs comprises the following steps:

[0020] Curcumin, tetrakis(4-carboxyphenyl)porphyrin and cobalt salt were ultrasonically dispersed in a mixed solvent of DMF and ethanol; then a solvothermal reaction was carried out, the mixture was filtered, washed, and dried in vacuum at 60° C. to constant weight to obtain Co-TCPP-curcumin MOFs.

[0021] In a preferred embodiment, the volume ratio of DMF to ethanol is 3:1; the solvent thermal reaction is carried out at 80 to 120° C. for 20 to 30 hours; and the vacuum drying temperature is 60° C.

[0022] In a further preferred embodiment, the molar ratio of the curcumin, tetrakis(4-carboxyphenyl)porphyrin and the cobalt salt is 0.2-0.4:1.2-1.6:6-12; and the cobalt salt is one of cobalt nitrate, cobalt chloride and cobalt acetate.

[0023] In the present invention, a preferred technical solution is that the preparation method of the CTAB-modified zinc-aluminum hydrotalcite comprises the following steps:

[0024] Ultrasonic dispersion of zinc salt and aluminum salt in deionized water, stirring for 20 to 40 minutes, and then adding a certain amount of urea; stirring for 10 to 20 minutes, transferring to a hydrothermal reactor for hydrothermal reaction, centrifuging, washing, and vacuum drying at 50 to 80°C for 10 to 20 hours to obtain zinc-aluminum hydrotalcite; ultrasonic dispersion of zinc-aluminum hydrotalcite and CTAB in deionized water, and then stirring reaction, cooling to room temperature, filtering, washing, and vacuum drying at 50 to 80°C for 10 to 20 hours to obtain CTAB-modified zinc-aluminum hydrotalcite.

[0025] In a preferred embodiment, the molar ratio of the zinc salt to the aluminum salt is 2:1; the zinc salt is at least one of zinc nitrate, zinc chloride, and zinc acetate; and the aluminum salt is aluminum acetate.

[0026] In a further preferred embodiment, the molar ratio of the zinc salt to urea is 1:4-6; and the hydrothermal reaction is carried out at 130-150° C. for 8-12 hours.

[0027] In a further preferred embodiment, the mass ratio of the zinc-aluminum hydrotalcite to CTAB is 100:11-15; and the stirring reaction is carried out at 60-80° C. for 3-9 hours.

[0028] Based on the above-mentioned method for preparing an antibacterial and mildew-proof PP plastic, the preparation method comprises the following steps:

[0029] Polypropylene resin, dispersant, plasticizer, antioxidant, Co-TCPP-curcumin MOFs and CTAB-modified zinc-aluminum hydrotalcite are added to a torque rheometer for blending at a temperature of 175-195°C for 10-30 minutes, and then the materials are hot-pressed to obtain antibacterial and mildew-proof PP plastic.

[0030] Preferably, the conditions for the hot pressing molding are: a temperature of 175-185° C. and a pressure of 6-9 MPa.

[0031] The present invention has the following beneficial effects:

[0032] By using curcumin and tetrakis (4-carboxyphenyl) porphyrin as ligands to prepare a metal-metal organic framework, the antibacterial property of the ligand can be used to improve the antibacterial property of PP plastics, and the mechanical properties of PP plastics can also be improved. The hydrotalcite of the present application has antibacterial properties. By modifying the zinc-aluminum hydrotalcite by CTAB, not only the dispersibility of the zinc-aluminum hydrotalcite in the PP plastic is improved, but also the antibacterial property and mechanical properties are improved. The antibacterial and mildew-proof PP plastic of the present invention has excellent antibacterial and mechanical properties. DETAILED DESCRIPTION

[0033] The present invention is further described below with reference to specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0034] Polypropylene resin: EM248U, LyondellBasell Industries; the dispersant is polyethylene wax or calcium stearate; the antioxidant is antioxidant 1010.

[0035] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0036] Example 1

[0037] An antibacterial and mildew-proof PP plastic, comprising the following components in parts by weight:

[0038]

[0039] The plasticizer is dioctyl phthalate (DOP).

[0040] The preparation method of the Co-TCPP-curcumin MOFs comprises the following steps:

[0041] 0.3 mol of curcumin, 1.4 mol of tetrakis(4-carboxyphenyl)porphyrin and 9 mol of cobalt nitrate were ultrasonically dispersed in a 200 mL DMF and ethanol mixed solvent, wherein the volume ratio of DMF to ethanol was 3:1; then the mixture was solvothermally reacted at 100 °C for 26 h, filtered, washed, and vacuum dried at 60 °C to constant weight to obtain Co-TCPP-curcumin MOFs.

[0042] The preparation method of CTAB-modified zinc-aluminum hydrotalcite comprises the following steps:

[0043] Ultrasonic dispersion of 2 mol zinc nitrate and 1 mol aluminum acetate in 150 mL deionized water, stirring for 30 min, then adding 10 mol urea; stirring for 15 min, transferring to a hydrothermal reactor, reacting at 140 ° C for 10 h, centrifuging, washing, and vacuum drying at 70 ° C for 16 h to obtain zinc aluminum hydrotalcite; ultrasonic dispersion of 100 g zinc aluminum hydrotalcite and 13 g CTAB in 150 mL deionized water, then stirring and reacting at 70 ° C for 6 h, cooling to room temperature, filtering, washing, and vacuum drying at 70 ° C for 16 h to obtain CTAB-modified zinc aluminum hydrotalcite.

[0044] A method for preparing antibacterial and mildew-proof PP plastic comprises the following steps:

[0045] Polypropylene resin, dispersant, plasticizer, antioxidant, Co-TCPP-curcumin MOFs and CTAB-modified zinc-aluminum hydrotalcite were added to a torque rheometer for blending at a temperature of 185°C for 20 min. The materials were then hot-pressed at a temperature of 180°C and a pressure of 8 MPa to obtain antibacterial and mildew-proof PP plastic.

[0046] Example 2

[0047] An antibacterial and mildew-proof PP plastic, comprising the following components in parts by weight:

[0048]

[0049] The plasticizer is dioctyl adipate (DOA).

[0050] The preparation method of the Co-TCPP-curcumin MOFs comprises the following steps:

[0051] 0.4 mol of curcumin, 1.6 mol of tetrakis(4-carboxyphenyl)porphyrin and 12 mol of cobalt chloride were ultrasonically dispersed in a 200 mL DMF and ethanol mixed solvent, wherein the volume ratio of DMF to ethanol was 3:1; then, the mixture was solvothermally reacted at 120 °C for 20 h, filtered, washed, and vacuum dried at 60 °C to constant weight to obtain Co-TCPP-curcumin MOFs.

[0052] The preparation method of CTAB-modified zinc-aluminum hydrotalcite comprises the following steps:

[0053] Ultrasonic dispersion of 2 mol zinc chloride and 1 mol aluminum acetate in 150 mL deionized water, stirring for 40 min, then adding 12 mol urea; stirring for 20 min, transferring to a hydrothermal reactor, reacting at 150 ° C for 8 h, centrifuging, washing, and vacuum drying at 80 ° C for 10 h to obtain zinc aluminum hydrotalcite; ultrasonic dispersion of 100 g zinc aluminum hydrotalcite and 15 g CTAB in 150 mL deionized water, then stirring and reacting at 80 ° C for 3 h, cooling to room temperature, filtering, washing, and vacuum drying at 80 ° C for 10 h to obtain CTAB-modified zinc aluminum hydrotalcite.

[0054] A method for preparing antibacterial and mildew-proof PP plastic comprises the following steps:

[0055] Polypropylene resin, dispersant, plasticizer, antioxidant, Co-TCPP-curcumin MOFs and CTAB-modified zinc-aluminum hydrotalcite were added to a torque rheometer for blending at a temperature of 195°C for 10 min. The materials were then hot-pressed at a temperature of 185°C and a pressure of 6 MPa to obtain antibacterial and mildew-proof PP plastic.

[0056] Example 3

[0057] An antibacterial and mildew-proof PP plastic, comprising the following components in parts by weight:

[0058] 100 parts of polypropylene resin;

[0059] 4 parts of dispersant;

[0060] 4 parts of plasticizer;

[0061] 1 part antioxidant;

[0062] Co-TCPP-curcumin MOFs 6 parts;

[0063] 3 parts of CTAB-modified zinc-aluminum hydrotalcite;

[0064] The plasticizer is dioctyl phthalate (DOP).

[0065] The preparation method of the Co-TCPP-curcumin MOFs comprises the following steps:

[0066] 0.2 mol of curcumin, starch tetra(4-carboxyphenyl)porphyrin and 6 mol of cobalt acetate were ultrasonically dispersed in 200 mL of a mixed solvent of DMF and ethanol, wherein the volume ratio of DMF to ethanol was 3:1; then the mixture was solvothermally reacted at 80 °C for 30 h, filtered, washed, and vacuum dried at 60 °C to constant weight to obtain Co-TCPP-curcumin MOFs.

[0067] The preparation method of CTAB-modified zinc-aluminum hydrotalcite comprises the following steps:

[0068] Ultrasonic dispersion of 2 mol zinc acetate and 1 mol aluminum acetate in 150 mL deionized water, stirring for 20 min, then adding 8 mol urea; stirring for 10 min, transferring to a hydrothermal reactor, reacting at 130 ° C for 12 h, centrifuging, washing, and vacuum drying at 50 ° C for 20 h to obtain zinc-aluminum hydrotalcite; ultrasonic dispersion of 100 g zinc-aluminum hydrotalcite and 11 g CTAB in 150 mL deionized water, then stirring and reacting at 60 ° C for 9 h, cooling to room temperature, filtering, washing, and vacuum drying at 50 ° C for 20 h to obtain CTAB-modified zinc-aluminum hydrotalcite.

[0069] A method for preparing antibacterial and mildew-proof PP plastic comprises the following steps:

[0070] Polypropylene resin, dispersant, plasticizer, antioxidant, Co-TCPP-curcumin MOFs and CTAB-modified zinc-aluminum hydrotalcite were added to a torque rheometer for blending at a temperature of 175°C for 30 min. The materials were then hot-pressed at a temperature of 175°C and a pressure of 9 MPa to obtain antibacterial and mildew-proof PP plastic.

[0071] Comparative Example 1

[0072] The difference between Comparative Example 1 and Example 1 is that an equal amount of Co-TCPP MOFs is used to replace Co-TCPP-curcumin MOFs. The preparation method of the Co-TCPP MOFs comprises the following steps:

[0073] 1.7 mol of tetrakis(4-carboxyphenyl)porphyrin and 9 mol of cobalt nitrate were ultrasonically dispersed in 200 mL of a mixed solvent of DMF and ethanol, wherein the volume ratio of DMF to ethanol was 3:1; then the mixture was solvothermally reacted at 100°C for 26 h, filtered, washed, and vacuum dried at 60°C to constant weight to obtain Co-TCPP MOFs.

[0074] Comparative Example 2

[0075] The difference between Comparative Example 2 and Example 1 is that an equal amount of zinc-aluminum hydrotalcite is used to replace the CTAB-modified zinc-aluminum hydrotalcite. The preparation method of the zinc-aluminum hydrotalcite comprises the following steps:

[0076] 2 mol of zinc chloride and 1 mol of aluminum acetate were ultrasonically dispersed in 150 mL of deionized water, stirred for 40 min, and then 12 mol of urea was added; stirred for 20 min, transferred to a hydrothermal reactor, reacted at 150° C. for 8 h, centrifuged, washed, and vacuum dried at 80° C. for 10 h to obtain zinc-aluminum hydrotalcite.

[0077] Comparative Example 3

[0078] The difference between Comparative Example 3 and Example 1 is that 9 parts of Co-TCPP-curcumin MOFs are used to replace 4 parts of Co-TCPP-curcumin MOFs and 5 parts of CTAB-modified zinc-aluminum hydrotalcite.

[0079] The performance of Examples 1-3 and Comparative Examples 1-3 were tested, and the specific test results are shown in Table 1.

[0080] Among them, the bending strength is tested using GB / T9341-2008;

[0081] Impact strength, tested according to GB / T1043-1993;

[0082] The antibacterial performance was tested using QB / T 2591-2003 and the antibacterial performance was tested for 10 hours.

[0083] Table 1:

[0084]

[0085] It can be seen from Table 1 that the antibacterial and mildew-proof PP plastic prepared by the present invention has excellent mechanical properties and antibacterial properties, especially under the joint promotion of Co-TCPP-curcumin MOFs and CTAB-modified zinc-aluminum hydrotalcite, the mechanical properties and antibacterial properties reach the best.

[0086] The anti-mildew effects of Examples 1-3 were tested by JIS Z2911:2018 and all reached Grade 0.

[0087] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. An antibacterial and mildew-proof PP plastic, characterized in that: By weight, it includes the following components: 100 parts of polypropylene resin; 4 to 8 parts of dispersant; 2 to 4 parts of plasticizer; 1-2 parts of antioxidant; Co-TCPP-curcumin MOFs 2 to 6 parts; 3 to 7 parts of CTAB-modified zinc-aluminum hydrotalcite.

2. The antibacterial and mildew-proof PP plastic according to claim 1, characterized in that: The preparation method of the Co-TCPP-curcumin MOFs comprises the following steps: Curcumin, tetrakis(4-carboxyphenyl)porphyrin and cobalt salt were ultrasonically dispersed in a mixed solvent of DMF and ethanol; then a solvothermal reaction was carried out, the mixture was filtered, washed, and dried in vacuum at 60° C. to constant weight to obtain Co-TCPP-curcumin MOFs.

3. The antibacterial and mildew-proof PP plastic according to claim 2, characterized in that: The volume ratio of DMF to ethanol is 3:1; the conditions of the solvothermal reaction are 80-120° C. for 20-30 hours; and the temperature of the vacuum drying is 60° C.

4. The antibacterial and mildew-proof PP plastic according to claim 2, characterized in that: The molar ratio of the curcumin, tetrakis(4-carboxyphenyl)porphyrin and the cobalt salt is 0.2-0.4:1.2-1.6:6-12; and the cobalt salt is one of cobalt nitrate, cobalt chloride and cobalt acetate.

5. The antibacterial and mildew-proof PP plastic according to claim 1, characterized in that: The preparation method of the CTAB-modified zinc-aluminum hydrotalcite comprises the following steps: Ultrasonic dispersion of zinc salt and aluminum salt in deionized water, stirring for 20 to 40 minutes, and then adding a certain amount of urea; stirring for 10 to 20 minutes, transferring to a hydrothermal reactor for hydrothermal reaction, centrifuging, washing, and vacuum drying at 50 to 80°C for 10 to 20 hours to obtain zinc-aluminum hydrotalcite; ultrasonic dispersion of zinc-aluminum hydrotalcite and CTAB in deionized water, and then stirring reaction, cooling to room temperature, filtering, washing, and vacuum drying at 50 to 80°C for 10 to 20 hours to obtain CTAB-modified zinc-aluminum hydrotalcite.

6. The antibacterial and mildew-proof PP plastic according to claim 5, characterized in that: The molar ratio of the zinc salt to the aluminum salt is 2:1; the zinc salt is at least one of zinc nitrate, zinc chloride and zinc acetate; and the aluminum salt is aluminum acetate.

7. The antibacterial and mildew-proof PP plastic according to claim 5, characterized in that: The molar ratio of the zinc salt to the urea is 1:4-6; the hydrothermal reaction conditions are 130-150° C. for 8-12 hours.

8. The antibacterial and mildew-proof PP plastic according to claim 5, characterized in that: The mass ratio of the zinc-aluminum hydrotalcite to CTAB is 100:11-15; the stirring reaction condition is stirring the reaction at 60-80° C. for 3-9 hours.

9. The method for preparing an antibacterial and mildew-proof PP plastic according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: Polypropylene resin, dispersant, plasticizer, antioxidant, Co-TCPP-curcumin MOFs and CTAB-modified zinc-aluminum hydrotalcite are added to a torque rheometer for blending at a temperature of 175-195°C for 10-30 minutes, and then the materials are hot-pressed to obtain antibacterial and mildew-proof PP plastic.

10. The method for preparing an antibacterial and mildew-proof PP plastic according to claim 9, characterized in that: The conditions for the hot pressing molding are: a temperature of 175-185° C. and a pressure of 6-9 MPa.

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