PET packaging material

Abstract

The invention relates to a PET packaging material, and belongs to the technical field of packaging materials. According to the invention, nano-silica is modified, and a polymerizable anhydride group is grafted on the surface of nano-silica, so that the nano-silica can react with a terminal hydroxyl group of a PET oligomer, chemical bonding of nano-silica and a PET group is established, the compatibility of nano-silica in PET is effectively improved, and crystal distribution is optimized; according to the present invention, the surface of the modified nanometer silicon dioxide has the positive electricity, such that the stress transmission efficiency inside the material is improved, the tensile strength and the impact resistance of the PET packaging material are effectively improved, the surface resistance of the PET packaging material can be effectively reduced, the electrostatic hazard can be reduced, and the good antibacterial property can be provided for the PET packaging material.

Description

Technical Field

[0001] The present invention belongs to the technical field of packaging materials, and in particular, relates to a PET packaging material, and more particularly, to a medical antibacterial and antistatic packaging material. Background Art

[0002] Polyethylene terephthalate (PET) is widely used in the field of medical packaging materials due to its excellent physical and mechanical properties, chemical stability and good gas barrier properties. Compared with traditional glass packaging, PET has the advantages of being lightweight and having strong impact resistance. However, PET is a polar insulating material with a high surface resistance. It is easy to generate static electricity due to friction during processing, transportation or use. The static electricity generated on the surface can absorb pollutants such as dust and bacteria, which not only affects the cleanliness of the packaging, but also may cause the risk of microbial contamination of drugs. Although the surface resistance of PET materials can be reduced and the antistatic properties of PET materials can be improved by adding antistatic agents, the migration of antistatic agents will destroy the chemical stability of PET, which may affect the safety performance of drugs. In addition, PET does not have antibacterial properties and cannot inhibit the growth of microorganisms by itself. In a humid environment, the PET surface is more susceptible to microbial contamination. To solve the above technical defects, the present invention prepares a PET packaging material with good antibacterial and antistatic properties. Summary of the Invention

[0003] The object of the present invention is to provide a PET packaging material for solving the problems mentioned in the above background technology.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A PET packaging material is prepared by the following steps:

[0006] S1, the silane coupling agent KH-431, nano-silica, ethanol solution were mixed in a three-necked flask, a condenser and a thermometer were installed, magnetic stirring was turned on, glacial acetic acid was added to the three-necked flask to adjust the pH of the system to 4-5, and then the mixture was reacted at a temperature of 40-80 ° C for 4-24 hours. After the reaction was completed, the nano-silica was filtered out and washed with anhydrous ethanol and deionized water in sequence, and then dried to obtain chloropropylated nano-silica;

[0007] S2, mixing chloropropylated nano-silica, 4-methylfuro[3,4-b]pyridine-5,7-dione, and acetonitrile in a three-necked flask, equipped with a condenser and a thermometer, turning on magnetic stirring, and reacting at a temperature of 60-82°C for 8-16 hours. After the reaction is completed, filtering out the nano-silica and washing it with anhydrous ethanol and deionized water in sequence, and then drying it to obtain modified nano-silica;

[0008] S3. Add terephthalic acid, ethylene glycol, a catalyst, and a heat stabilizer into a stainless steel reactor protected by nitrogen, and react at a temperature of 220-240° C. for 4-5 hours to obtain a PET oligomer. Then, add modified nano-silica into the stainless steel reactor, and then reduce the pressure in the stainless steel reactor to below 1 KPa. The reaction is continued at a temperature of 270-290° C. for 4-6 hours to complete the polycondensation. After the reaction is completed, the product is cooled to room temperature and pelletized and dried to obtain a modified PET masterbatch.

[0009] S4, mixing the modified PET masterbatch and the antioxidant, adding the mixture into a twin-screw extruder, and then melt-extruded, and blow-molding to obtain the PET packaging material.

[0010] Furthermore, the silane coupling agent KH-431 is 3-chloropropyltrimethoxysilane.

[0011] Furthermore, the particle size of the nano-silicon dioxide is 50 to 150 nm.

[0012] Furthermore, the ethanol solution is an ethanol aqueous solution with a volume fraction of 60 to 80%.

[0013] Furthermore, the catalyst is one of antimony glycol and antimony trioxide.

[0014] Furthermore, the heat stabilizer is one of triethyl phosphate and triphenyl phosphate.

[0015] Furthermore, the antioxidant is one of antioxidant 1010 and antioxidant 168.

[0016] Furthermore, the mass ratio of silane coupling agent KH-431, nano-silica and ethanol solution in S1 is 8-12:10-12:250-400.

[0017] Furthermore, the mass ratio of chloropropylated nano-silica, 4-methylfuro[3,4-b]pyridine-5,7-dione, and acetonitrile in S2 is 12-15:7.2-9.4:100-160.

[0018] Furthermore, the mass ratio of terephthalic acid, ethylene glycol, catalyst, thermal stabilizer and modified nano-silica in S3 is 83-99:42-66:0.025-0.08:0.125-0.625:12-16.

[0019] Furthermore, the mass ratio of the modified PET masterbatch to the antioxidant in S4 is 100-120:0.2-0.5.

[0020] Furthermore, the extrusion temperature of the twin-screw extruder in S4 is 270-290°C.

[0021] Beneficial effects of the present invention:

[0022] 1) The present invention grafts a silane coupling agent KH-431 onto the surface of nano-silica, introduces chloropropyl groups onto the surface of the nano-silica, and then utilizes the chlorine atoms of the chloropropylated nano-silica and the nitrogen atoms on the pyridine ring of 4-methylfuro[3,4-b]pyridine-5,7-dione to react to form a quaternary ammonium salt to obtain a modified nano-silica. The surface of the unmodified nano-silica is rich in hydrophilic hydroxyl groups and has poor compatibility with hydrophobic PET. Direct addition to PET may cause agglomeration and stress concentration due to poor dispersibility, significantly reducing the tensile properties and impact strength of the PET. However, the present invention grafts polymerizable anhydride groups onto the surface of the modified nano-silica, which can react with the terminal hydroxyl groups of PET oligomers to establish chemical bonding between the nano-silica and PET groups, optimize crystal distribution, improve stress transfer efficiency within the material, and effectively improve the tensile strength and impact resistance of the PET packaging material.

[0023] 2) The modified nano-silica of the present invention has a pyridyl quaternary ammonium salt structure grafted onto its surface. The pyridyl quaternary ammonium salt has a good bactericidal effect and can impart lasting antibacterial properties to PET packaging materials. It can also use its own positive charge to form a conductive path inside the PET substrate, thereby reducing the surface resistance of the material and improving the antistatic properties of the PET packaging material. The antibacterial and antistatic components are chemically bonded to the PET material, so there is no risk of migration during use and the chemical stability of PET is not damaged. DETAILED DESCRIPTION

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0025] In this article, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0026] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0027] As used herein, when referring to numerical ranges, unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values of the range, as well as every value between such minimum and maximum values. Furthermore, when a range refers to an integer, every integer between the minimum and maximum values of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges subsumed therein.

[0028] In this document, when referring to a range, if the unit is followed only by the right endpoint, it means that the units of the left and right endpoints are the same. For example, 220-240°C means that the units of both the left endpoint "220" and the right endpoint "240" are °C.

[0029] Only certain numerical ranges are specifically disclosed herein. However, any lower limit may be combined with any upper limit to form an unspecified range; and any lower limit may be combined with other lower limits to form an unspecified range, and similarly, any upper limit may be combined with any other upper limit to form an unspecified range. In addition, each individually disclosed point or single value may itself serve as a lower limit or upper limit and be combined with any other point or single value, or with other lower limits or upper limits, to form an unspecified range.

[0030] Example 1

[0031] A PET packaging material is prepared by the following steps:

[0032] S1. Mix 12 parts by mass of a silane coupling agent KH-431, 12 parts of nano-silica with a particle size of 50 to 150 nm, and 400 parts by volume of a 60% ethanol aqueous solution in a three-necked flask, install a condenser and a thermometer, turn on magnetic stirring, add glacial acetic acid to the three-necked flask to adjust the pH of the system to 4, and then react at a temperature of 40° C. for 24 hours. After the reaction is completed, filter out the nano-silica and wash it with anhydrous ethanol and deionized water in sequence, and then dry it to obtain chloropropylated nano-silica;

[0033] S2. Mix 15 parts of chloropropylated nano-silica, 9.4 parts of 4-methylfuro[3,4-b]pyridine-5,7-dione, and 160 parts of acetonitrile in a three-necked flask, install a condenser and a thermometer, start magnetic stirring, and react at 60°C for 16 hours. After the reaction is completed, filter out the nano-silica and wash it with anhydrous ethanol and deionized water in sequence, and then dry it to obtain modified nano-silica;

[0034] S3. Add 99 parts of terephthalic acid, 66 parts of ethylene glycol, 0.08 parts of antimony trioxide, and 0.625 parts of triphenyl phosphate into a stainless steel reactor protected by nitrogen, and react at a temperature of 220° C. for 5 hours to obtain a PET oligomer. Then, add 16 parts of modified nano-silica to the stainless steel reactor, and then pump the pressure in the stainless steel reactor to 900 Pa. The reaction is carried out at a temperature of 270° C. for 6 hours to complete the polycondensation. After the reaction is completed, the product is cooled to room temperature and pelletized and dried to obtain a modified PET masterbatch.

[0035] S4. 120 parts by mass of modified PET masterbatch and 0.5 parts of antioxidant 1010 were mixed and added into a twin-screw extruder. The mixture was melt-extruded at a temperature of 270° C. and then blow-molded to obtain the PET packaging material.

[0036] Example 2

[0037] A PET packaging material is prepared by the following steps:

[0038] S1. Mix 10 parts by mass of a silane coupling agent KH-431, 11 parts of nano-silica with a particle size of 50 to 150 nm, and 325 parts by volume of a 70% ethanol aqueous solution in a three-necked flask, install a condenser and a thermometer, turn on magnetic stirring, add glacial acetic acid to the three-necked flask to adjust the pH of the system to 4.5, and then react at a temperature of 60° C. for 12 hours. After the reaction is completed, filter out the nano-silica and wash it with anhydrous ethanol and deionized water in sequence, and then dry it to obtain chloropropylated nano-silica;

[0039] S2. Mix 13.5 parts of chloropropylated nano-silica, 8.3 parts of 4-methylfuro[3,4-b]pyridine-5,7-dione, and 130 parts of acetonitrile in a three-necked flask, install a condenser and a thermometer, start magnetic stirring, and react at 71°C for 12 hours. After the reaction is completed, filter out the nano-silica, wash it with anhydrous ethanol and deionized water, and then dry it to obtain modified nano-silica;

[0040] S3. Add 91 parts of terephthalic acid, 54 parts of ethylene glycol, 0.0525 parts of ethylene glycol antimony or antimony trioxide, and 0.375 parts of triethyl phosphate or triphenyl phosphate into a stainless steel reactor protected by nitrogen, and react at a temperature of 230° C. for 4.5 hours to obtain a PET oligomer. Then, add 14 parts of modified nano-silica to the stainless steel reactor, and then pump the pressure in the stainless steel reactor to 500 Pa. The reaction is carried out at a temperature of 280° C. for 5 hours to complete the polycondensation. After the reaction is completed, the product is cooled to room temperature and pelletized and dried to obtain a modified PET masterbatch;

[0041] S4. 110 parts by mass of modified PET masterbatch and 0.35 parts of antioxidant 168 were mixed and added to a twin-screw extruder. The mixture was melt-extruded at a temperature of 280° C. and then blow-molded to obtain the PET packaging material.

[0042] Example 3

[0043] A PET packaging material is prepared by the following steps:

[0044] S1. Mix 8 parts of silane coupling agent KH-431, 10 parts of nano-silica with a particle size of 50 to 150 nm, and 250 parts of an 80% ethanol aqueous solution in a three-necked flask, install a condenser and a thermometer, turn on magnetic stirring, add glacial acetic acid to the three-necked flask to adjust the pH of the system to 5, and then react at a temperature of 80° C. for 4 hours. After the reaction is completed, filter out the nano-silica and wash it with anhydrous ethanol and deionized water in sequence, and then dry it to obtain chloropropylated nano-silica;

[0045] S2. Mix 12 parts by mass of chloropropylated nano-silica, 7.2 parts of 4-methylfuro[3,4-b]pyridine-5,7-dione, and 100 parts of acetonitrile in a three-necked flask, install a condenser and a thermometer, start magnetic stirring, and react at 82°C for 8 hours. After the reaction is completed, filter out the nano-silica, wash it with anhydrous ethanol and deionized water in sequence, and then dry it to obtain modified nano-silica;

[0046] S3. Add 83 parts of terephthalic acid, 42 parts of ethylene glycol, 0.025 parts of ethylene glycol antimony, and 0.125 parts of triethyl phosphate into a stainless steel reactor protected by nitrogen, and react at a temperature of 240° C. for 4 hours to obtain a PET oligomer. Then, add 12 parts of modified nano-silica to the stainless steel reactor, and then pump the pressure in the stainless steel reactor to 100 Pa. The reaction is carried out at a temperature of 290° C. for 4 hours to complete the polycondensation. After the reaction is completed, the product is cooled to room temperature and pelletized and dried to obtain a modified PET masterbatch.

[0047] S4. 100 parts by mass of modified PET masterbatch and 0.2 parts by mass of antioxidant 1010 were mixed and added into a twin-screw extruder. The mixture was melt-extruded at a temperature of 290° C. and then blow-molded to obtain the PET packaging material.

[0048] Comparative Example 1

[0049] A PET packaging material is made by the following steps:

[0050] S1. Add 83 parts of terephthalic acid, 42 parts of ethylene glycol, 0.025 parts of antimony ethylene glycol, and 0.125 parts of triethyl phosphate into a stainless steel reactor protected by nitrogen, and react at a temperature of 240°C for 4 hours to obtain a PET oligomer. Then, add 12 parts of untreated nano-silica with a particle size of 50 to 150 nm into the stainless steel reactor. Then, reduce the pressure in the stainless steel reactor to 100 Pa, and react at a temperature of 290°C for 4 hours to complete the polycondensation. After the reaction, cool the product to room temperature and pelletize and dry it to obtain a PET masterbatch.

[0051] S2. 100 parts by mass of PET masterbatch and 0.2 parts by mass of antioxidant 1010 were mixed and added into a twin-screw extruder. The mixture was melt-extruded at a temperature of 290° C. and then blow-molded to obtain the PET packaging material.

[0052] Experimental example

[0053] The tensile performance test, antibacterial performance test and surface resistance test were performed on Examples 1 to 3 and Comparative Example 1, respectively. The tensile performance test was performed in accordance with the national standard GB / T 1040.2-2006 "Determination of tensile properties of plastics", and the antibacterial performance test was performed in accordance with the national standard GB / T 31402-2015 "Test method for antibacterial properties of plastic surfaces" to test the antibacterial rates of Escherichia coli and Staphylococcus aureus. Comparative Example 1 was used as the control group, and the surface resistance test was performed in accordance with the national standard GB / T 1410-2006 "Test method for volume resistivity and surface resistivity of solid insulating materials". The lower the surface resistance, the better the antistatic ability. The test results are shown in Table 1:

[0054] Table 1

[0055]

[0056]

[0057] It can be seen from Table 1 that the PET packaging materials of the present invention in Examples 1 to 3 have good antibacterial properties, and have better tensile strength and surface resistance than those in Comparative Example 1, indicating that the use of the modified nano-silica of the present invention can effectively improve the tensile strength, antibacterial properties and antistatic properties of the material.

[0058] Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help those skilled in the art understand the method of the present invention and its core ideas, including the best mode, and also enable those skilled in the art to practice the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements that are similar to the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, then these other embodiments should also be included in the scope of the claims.

Claims

1. A PET packaging material, characterized in that: Prepared by the following steps: Preparation of modified nano-silica: Grafting silane coupling agent KH-431 on the surface of nano-silica to obtain chloropropylated nano-silica, and then grafting 4-methylfuro[3,4-b]pyridine-5,7-dione on the surface of chloropropylated nano-silica through quaternary ammonium salt reaction to obtain modified nano-silica; Preparation of PET packaging materials: terephthalic acid, ethylene glycol, a catalyst, and a heat stabilizer are polymerized under nitrogen protection conditions to obtain PET oligomers, and then nano-silicon dioxide is added to the PET oligomers. After polycondensation, cooling, pelletizing, and drying, modified PET masterbatch is obtained. The modified PET masterbatch is mixed with an antioxidant and then melt-extruded and blow-molded to obtain PET packaging materials.

2. A PET packaging material according to claim 1, characterized in that, The particle size of the nano-silicon dioxide is 50 to 150 nm.

3. A PET packaging material according to claim 1, characterized in that, The catalyst is one of ethylene glycol antimony and antimony trioxide.

4. A PET packaging material according to claim 1, characterized in that, The heat stabilizer is one of triethyl phosphate and triphenyl phosphate.

5. A PET packaging material according to claim 1, characterized in that: The antioxidant is one of antioxidant 1010 and antioxidant 168.

6. A PET packaging material according to claim 1, characterized in that: The mass ratio of the silane coupling agent KH-431 to the nano-silicon dioxide is 8-12:10-12.

7. A PET packaging material according to claim 1, characterized in that: The mass ratio of chloropropylated nano-silica to 4-methylfuro[3,4-b]pyridine-5,7-dione is 12-15:7.2-9.

4.

8. The PET packaging material according to claim 1, characterized in that: The mass ratio of terephthalic acid, ethylene glycol, catalyst, heat stabilizer and modified nano silicon dioxide is 83-99:42-66:0.025-0.08:0.125-0.625:12-16.

9. A PET packaging material according to claim 1, characterized in that: The mass ratio of the modified PET masterbatch to the antioxidant is 100-120:0.2-0.

5.

10. The PET packaging material according to claim 1, characterized in that: The polymerization conditions are: reaction at a temperature of 220-240° C. for 4-5 hours; the condensation conditions are: reaction at a temperature of 270-290° C. for 4-6 hours; and the temperature conditions for melt extrusion are 270-290° C.

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