Process for the production of polyolefin-based materials

Abstract

The present invention relates to a method for manufacturing polyolefin materials. The method uses a specific polyolefin, a specific heat-resistant additive, a specific weight ratio of the heat-resistant additive and the anti-sticking agent, and a specific temperature for mixing and processing to improve the anti-sticking property and heat resistance of the manufactured polyolefin materials.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a polyolefin material, and more particularly to a method for manufacturing a polyolefin material having anti-sticking and heat-resistant properties. Background Technology

[0002] Polyolefin materials are thermoplastics with good processability, making them widely used in medical and consumer industries. Examples include leukocyte reduction filters, dialysis tubing, anti-adhesion catheters, syringes, cosmetic masks, and drinking water piping. These materials require anti-adhesion properties to avoid the drawbacks caused by adhesion of biomolecules such as blood, cells, and bacteria. Furthermore, they require heat resistance to prevent degradation (e.g., thermal decomposition or oxidation) caused by sudden conditions (such as high temperatures) during transportation or storage.

[0003] Existing methods for manufacturing polyolefin materials utilize anti-adhesion agents and antioxidants to provide the aforementioned anti-adhesion and heat resistance. The anti-adhesion agent is applied to the material surface via a coating process, which is time-consuming and wasteful of the anti-adhesion agent. Furthermore, the addition of antioxidants can easily lead to incompatibility issues between the antioxidant and the anti-adhesion agent.

[0004] In view of this, there is an urgent need to develop a new method for manufacturing polyolefin materials to improve the above-mentioned shortcomings. Summary of the Invention

[0005] In view of the above problems, one aspect of the present invention is to provide a method for manufacturing a polyolefin material. This manufacturing method obtains a polyolefin material with both anti-sticking and heat resistance by mixing and processing a specific polyolefin, a specific heat-resistant additive, and an anti-sticking agent in a specific weight ratio at a specific temperature.

[0006] According to one aspect of the present invention, a method for manufacturing a polyolefin material is provided. This method comprises providing a polyolefin material composition comprising 100 parts by weight of a polyolefin, 0.1 to 0.9 parts by weight of a heat-resistant additive, and 0.1 to 0.9 parts by weight of an anti-sticking agent. The polyolefin is polyethylene or polypropylene. The heat-resistant additive has the structure shown in formula (I):

[0007]

[0008] In formula (I), R1 represents a hydroxyl group, and R2, R3 and R4 each independently represent a methyl group, an ethyl group, a branched alkyl group with 3 to 18 carbon atoms, or a propionate group with 15 to 21 carbon atoms.

[0009] The anti-adhesive has repeating units as shown in formula (II-1) or formula (II-2):

[0010]

[0011] In formulas (II-1) and (II-2), R5 represents a hydrogen atom or a methyl group, R6 represents a straight-chain, branched, or cyclic alkyl or ester group having 3 to 18 carbon atoms, or an aromatic or heteroaryl group having 5 to 12 carbon atoms, and R7 represents -COOR' or -CONR”H, where R' and R” represent betaine, sulfobetaine, or carboxybetaine, R8 represents a hydrogen atom or a carboxyl group, where when R8 represents a hydrogen atom, R9 represents -COOR' or -CONR”H, and when R8 represents a carboxyl group, R9 represents a cationic group, p represents an integer from 5 to 120, q represents an integer from 5 to 120, and * represents a bond. The weight ratio of the heat-resistant additive to the anti-sticking agent is 0.5 to 2.

[0012] Then, the polyolefin material composition is mixed at 100°C to 120°C to obtain a mixture. Next, the mixture is granulated and compounded at 200°C to 240°C to obtain the polyolefin material.

[0013] According to one embodiment of the present invention, the melt index of polyethylene is 0.20 g / 10 min to 0.30 g / 10 min.

[0014] According to another embodiment of the present invention, the melt index of polypropylene is 1.5 g / 10 min to 2.5 g / 10 min.

[0015] According to another embodiment of the present invention, the heat-resistant additive has a first additive with a structure shown in formula (I-1) and a second additive with a structure shown in formula (I-2):

[0016]

[0017] In equation (I-1), R 21 and R 41 Each can be independently represented as methyl or ethyl, R 31 It represents 1-methylpentadecanyl; and

[0018]

[0019] In equation (I-2), R 22 and R 32 Each independently represents a methyl, ethyl, or branched alkyl group having 3 to 4 carbon atoms, R 42 It refers to a straight-chain alkyl group with 15 to 18 carbon atoms.

[0020] According to another embodiment of the present invention, the weight ratio of the first additive to the second additive is 3 to 5.

[0021] According to another embodiment of the present invention, the melting point of the second additive is 50°C to 55°C.

[0022] According to another embodiment of the present invention, R9 represents the cationic group as N,N-dimethylammonium ethylamino vinyl, N,N-dimethylammonium propylamino vinyl, N,N-dimethylammonium butylamino vinyl and N,N-dimethylammonium pentylamino vinyl.

[0023] According to another embodiment of the present invention, the ester group represented by R6 has a -COOR group. a The structure, where R a It refers to a straight-chain, branched, or cyclic alkyl group having 3 to 18 carbon atoms, or an aromatic or heteroaryl group having 5 to 12 carbon atoms.

[0024] According to another embodiment of the present invention, the manufacturing method excludes applying an anti-adhesion agent to the surface of a polyolefin material.

[0025] The method for manufacturing polyolefin materials according to the present invention involves mixing and processing a specific polyolefin, a specific heat-resistant additive, and a specific weight ratio of the heat-resistant additive to an anti-sticking agent at a specific temperature to obtain a polyolefin material that combines anti-sticking and heat resistance. Attached Figure Description

[0026] To gain a more complete understanding of the embodiments and advantages of the present invention, please refer to the following description and the accompanying drawings. It must be emphasized that the various features are not depicted to scale and are for illustrative purposes only.

[0027] The contents of the relevant attached images are explained below:

[0028] Figure 1 A flowchart illustrating a method for manufacturing a polyolefin material according to an embodiment of the present invention is provided. Detailed Implementation

[0029] The manufacture and use of embodiments of the present invention are discussed in detail below. However, it will be understood that the embodiments provide many applicable inventive concepts that can be implemented in a wide variety of specific contexts. The specific embodiments discussed are for illustrative purposes only and are not intended to limit the scope of the invention.

[0030] The term "anti-sticking property" as used in this invention refers to the evaluation of polyolefin materials using the antibacterial rate test described later. When the antibacterial rate is greater than 80%, the polyolefin material has good anti-sticking property.

[0031] The term "heat resistance" as used in this invention refers to the evaluation of polyolefin materials using the yellowing test described later. When the yellowing value is less than 35, the polyolefin material has good heat resistance.

[0032] Please see Figure 1 The method 100 for manufacturing polyolefin materials first provides a polyolefin material composition, as shown in operation 110. The polyolefin material composition includes a polyolefin, a heat-resistant additive, and an anti-sticking agent. This polyolefin is polyethylene or polypropylene. If the polyolefin is not polyethylene or polypropylene, it is difficult to perform the granulation and mixing steps at temperatures between 200°C and 240°C, thus reducing the heat resistance and / or anti-sticking properties of the resulting polyolefin material.

[0033] In some specific examples, the polyolefin is a polyethylene homopolymer or a polypropylene homopolymer to facilitate the granulation and compounding processes at temperatures between 220°C and 240°C, thereby improving the heat resistance and anti-sticking properties of the resulting polyolefin material. In these specific examples, polyvinyl chloride (PVC) may be excluded from the polyolefin list. Since PVC releases toxic gases such as hydrogen chloride and chlorine when heated to high temperatures (e.g., above 148°C), it is not suitable for the manufacturing method 100 of this invention.

[0034] In some embodiments, the melt index of the polyethylene is from 0.20 g / 10 min to 0.30 g / 10 min, and preferably 0.25 g / 10 min. In these embodiments, the polyethylene may be high-density polyethylene with a density of 0.94 g / cm³. 3 Up to 0.96 g / cm 3 And the molecular weight can be 10. 4 g / mole to 10 6 g / mole.

[0035] In other embodiments, the melt index of the polypropylene is from 1.5 g / 10 min to 2.5 g / 10 min, and preferably 2.0 g / 10 min. In these embodiments, the density of the polypropylene may be 0.895 g / cm³. 3 Up to 0.92 g / cm 3 And the molecular weight can be 10. 4 g / mole to 10 5 g / mole.

[0036] When the melt flow indices of polyethylene and polypropylene are within the aforementioned corresponding ranges, polyethylene or polypropylene can be easily and uniformly mixed with heat-resistant additives and anti-sticking agents, facilitating subsequent processing and thus improving the heat resistance and anti-sticking properties of the resulting polyolefin material. Preferably, the melt flow indices of both polyethylene and polypropylene are within the aforementioned corresponding ranges.

[0037] The heat-resistant additive has the structure shown in formula (I).

[0038]

[0039] In formula (I), R1 represents a hydroxyl group, and R2, R3, and R4 each independently represent a methyl group, an ethyl group, a branched alkyl group with 3 to 18 carbon atoms, or a propionate group with 15 to 21 carbon atoms. If R1, R2, R3, and R4 do not represent the aforementioned groups, the heat-resistant additive cannot improve the heat resistance of the resulting polyolefin material.

[0040] Preferably, the heat-resistant additive has a first additive with the structure shown in formula (I-1) and a second additive with the structure shown in formula (I-2):

[0041]

[0042] In equation (I-1), R 21 and R 41 Each can be independently represented as methyl or ethyl, R 31 It represents 1-methylpentadecanyl; and

[0043]

[0044] In equation (I-2), R 22 and R 32 Each independently represents a methyl, ethyl, or branched alkyl group having 3 to 4 carbon atoms, R 42 It refers to a straight-chain alkyl group with 15 to 18 carbon atoms.

[0045] Incidentally, the anti-adhesion agent is prepared via free radical polymerization, in which the catalyst used (such as azobisisobutyronitrile, AIBN) generates free radicals to initiate the polymerization reaction. These free radicals then react with the double bonds on the carbon chains of the reactant molecules (such as monomers) to generate other free radicals. Furthermore, the catalyst also reacts with oxygen in the reaction environment to generate free radicals from oxygen molecules. These free radicals are neutralized after the reaction, but residual free radicals remain in the anti-adhesion agent, which reduces its thermal stability.

[0046] When a heat-resistant additive contains a first additive and a second additive, the first additive can capture free radicals generated by the catalyst and oxygen molecules, and the second additive can capture free radicals generated by monomer molecules. Therefore, when the first and second additives are used together, the thermal stability of the anti-sticking agent can be improved by capturing free radicals (hereinafter referred to as the synergistic effect), thereby improving the heat resistance of polyolefin materials and thus enhancing the heat resistance of the anti-sticking agent of polyolefin materials.

[0047] For example, the first additive may be 2,4-dimethyl-6-(1-methylpentadecanyl)phenol, and the second additive may be octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0048] In some embodiments, the weight ratio of the first additive to the second additive is 3 to 5, and preferably 4. When the weight ratio of the first additive to the second additive is within the aforementioned range, the two additives can better exert the aforementioned synergistic effect, thereby further improving the heat resistance and anti-sticking properties of the polyolefin material.

[0049] The melting points of the first and second additives are not particularly limited, but are intended to enable the completion of the mixing, granulation, and compounding processes described above. Preferably, the melting point of the second additive can be 50°C to 55°C, so as to increase the compatibility of the heat-resistant additive with the polyolefin and the anti-sticking agent, thereby further improving the heat resistance and anti-sticking properties of the polyolefin material.

[0050] The anti-adhesive has repeating units as shown in formula (II-1) or formula (II-2):

[0051]

[0052] In formulas (II-1) and (II-2), R5 represents a hydrogen atom or a methyl group, R6 represents a linear, branched, or cyclic alkyl or ester group having 3 to 18 carbon atoms, or an aromatic or heteroaryl group having 5 to 12 carbon atoms, and R7 represents -COOR' or -CONR”H, wherein R' and R” represent betaine, sulfobetaine, or carboxybetaine, R8 represents a hydrogen atom or a carboxyl group, wherein when R8 represents a hydrogen atom, R9 represents -COOR' or -CONR”H, and when R8 represents a carboxyl group, R9 represents a cationic group, p represents an integer from 5 to 120, q represents an integer from 5 to 120, and * represents a bonding site. Preferably, p and q represent integers from 90 to 110 or from 20 to 40 to improve the heat resistance and / or anti-sticking properties of the polyolefin material.

[0053] In some embodiments, the ester group represented by R6 has a -COOR group. a The structure of R a It represents a straight-chain, branched, or cyclic alkyl group having 3 to 18 carbon atoms, or an aromatic or heteroaryl group having 5 to 12 carbon atoms. Preferably, R a R9 represents a linear alkyl group with 3 to 6 carbon atoms to improve the heat resistance and / or anti-sticking properties of polyolefin materials. Specifically, R9 represents the cationic group N,N-dimethylammonium ethylamino vinyl, N,N-dimethylammonium propylamino vinyl, N,N-dimethylammonium butylamino vinyl, and N,N-dimethylammonium pentylamino vinyl.

[0054] In short, anti-adhesion agents are polymers with biionic or pseudo-biionic groups, such as negatively charged sulfonyl and carboxyl groups and positively charged ammonium groups. One end of this polymer is positively charged, and the other end is negatively charged, making the whole polymer electrically neutral. These biionic groups can generate Coulombic forces with water molecules, thus forming a thin hydrated layer (no more than 10 nm thick) on the surface of the resulting polyolefin material, thereby improving the anti-adhesion of the polyolefin material.

[0055] Based on the usage of 100 parts by weight of polyolefin, the usage of heat-resistant additive is 0.1 to 0.9 parts by weight, and the usage of anti-stick agent is 0.1 to 0.9 parts by weight. If the usage of heat-resistant additive is greater than the aforementioned corresponding amounts, the heat-resistant additive is prone to crystallization and precipitation, affecting the appearance of the polyolefin material and failing to effectively improve its heat resistance. If the usage of anti-stick agent is greater than the aforementioned corresponding amounts, the anti-stick agent cannot further improve the anti-stick properties of the polyolefin material, or may reduce its heat resistance. Conversely, if the usage of heat-resistant additive is too low (less than the aforementioned amounts), it cannot improve the heat resistance of the polyolefin material. If the usage of anti-stick agent is too low (less than the aforementioned amounts), it cannot improve the anti-stick properties of the polyolefin material.

[0056] Preferably, based on 100 parts by weight of polyolefin, the amount of heat-resistant additive used can be from 0.1 to 0.5 parts by weight, and the amount of anti-adhesive used is from 0.1 to 0.5 parts by weight. When the amounts of heat-resistant additive and anti-adhesive are within the aforementioned ranges, the heat-resistant additive can not only improve the thermal stability of the anti-adhesive, but also give the anti-adhesive a better antibacterial rate, thus further improving the heat resistance and anti-adhesion of polyolefin materials.

[0057] The ratio of the heat-resistant additive to the anti-sticking agent in this invention is 0.5 to 2. If this ratio is not within the aforementioned range, the heat resistance and / or anti-sticking properties of the polyolefin material will be reduced.

[0058] Please refer to the following: Figure 1 After operation 110, the polyolefin material composition is mixed at 100°C to 120°C to obtain a mixture, as shown in operation 120.

[0059] Following operation 120, the mixture is subjected to granulation and compounding steps at 200°C to 240°C to obtain a polyolefin material, as shown in operation 130. If the temperature of the granulation and compounding steps is too low (e.g., below 220°C), at least one component of the polyolefin material cannot be fully dissolved, making granulation and / or compounding impossible, thus affecting the anti-sticking properties and / or heat resistance of the polyolefin material. If the temperature of the granulation and compounding steps is too high (e.g., above 240°C), it is not conducive to the compounding of the polyolefin, heat-resistant additives, and anti-sticking agents, thus reducing the anti-sticking properties and / or heat resistance of the polyolefin material.

[0060] Manufacturing method 100 eliminates the need to apply anti-adhesion agents to the surface of polyolefin materials, simplifying the process and thus reducing material costs and saving time. Furthermore, since the resulting polyolefin material possesses excellent heat resistance and anti-adhesion properties throughout, the newly formed surface retains these properties even after subsequent cutting (e.g., into several parts) or trimming (e.g., into a predetermined shape). Therefore, the newly formed surface does not require further anti-adhesion treatment and can be used directly.

[0061] It should be noted that the aforementioned application may include applying an anti-adhesive or a mixture thereof (such as a solution containing an anti-adhesive) to the surface of a polyolefin material by means of external application such as coating, impregnation, and spraying.

[0062] The polyolefin material produced by the manufacturing method 100 of this invention possesses both good anti-adhesion and heat resistance, and therefore can be applied in the medical and consumer industrial fields. For example, in the medical field, the polyolefin material can be used as material for medical devices and testing equipment, such as dialysis tubes, leukocyte reduction filters, anti-adhesion urinary catheters, and syringes. In the medical field, the polyolefin material can also be used as material for facial masks and drinking water pipes.

[0063] Preparation of polyolefin materials

[0064] Example 1

[0065] The polyolefin material composition was mixed at 100°C to 120°C to obtain a mixture. The anti-sticking agent used had a structure as shown in Formula (II-1), where R5 represents a hydrogen atom, R6 represents a n-butyl ester group, R7 represents -CONR"H, R" represents a sulfobetaine group, and p and q both represent integers from 90 to 110. The mixture was then subjected to a granulation and compounding process at 220°C to 240°C to obtain the polyolefin material of Example 1. This polyolefin material was then evaluated using the evaluation methods described below.

[0066] Example 2 and Comparative Examples 1 to 3

[0067] The polyolefin materials of Examples 2 and Comparative Examples 1 to 3 were all prepared using a method similar to that of Example 1. The difference lies in the use of different polyolefins, heat-resistant additives, or temperatures for the granulation and mixing processes in Examples 2 and Comparative Examples 1 to 3. In the anti-sticking agent with the structure shown in Formula (II-2) used in Example 2, R5 represents a hydrogen atom, R6 represents a n-butyl ester group, R8 represents a carboxyl group, R9 represents N,N-dimethylammonium ethylamino vinyl, p represents an integer from 20 to 40, and q represents an integer from 50 to 70. The specific conditions and evaluation results of the aforementioned Examples 1 to 2 and Comparative Examples 1 to 3 are shown in Table 1 below.

[0068] Evaluation method

[0069] 1. Melt index test

[0070] The melt flow index test was conducted according to the standard test method ASTM D1238, with a load of 2.16 kg.

[0071] 2. Yellowing test

[0072] The yellowing test involves heating thin sheets of polyolefin materials under high-pressure oxygen, with polyethylene heated to 200°C for 10 minutes and polypropylene to 240°C for 7 minutes. The color change of the sheets is then observed, and the yellowing value is determined according to a yellowing standard. This yellowing value evaluates the heat resistance of polyolefin materials, including their tolerance to oxygen oxidation and high-temperature heating. A lower yellowing value indicates better heat resistance of the polyolefin material.

[0073] 3. Antibacterial rate test

[0074] The antibacterial rate was assessed using an E. coli adhesion assay to evaluate the anti-adhesion effect of polyolefin materials on bacteria. 1 mL of bacterial suspension was placed on a thin sheet formed from the polyolefin material and incubated at 37°C for 24 hours. Unadhered E. coli were then washed away with PBS buffer. After soaking and washing, the sheet was immersed in glutaraldehyde for 24 hours to fix the E. coli on the sheet. The E. coli adhered to the sheet were then observed using a laser scanning conjugate electron microscope to obtain the antibacterial rate per unit area (e.g., 1 cm²). 2 The percentage of E. coli adhering to the surface.

[0075] Table 1

[0076]

[0077]

[0078] Note: "-" indicates that the component was not used or the test was not performed.

[0079] Please refer to Table 1. The results of Examples 1 and 2 show that by using a specific polyolefin (polyethylene or polypropylene), a heat-resistant additive having the structure shown in Formula (I), and an anti-sticking agent having the structure shown in Formula (II-1) or Formula (II-2), and granulating and compounding at a temperature of 200°C to 240°C, the resulting polyolefin material has both good anti-sticking properties and heat resistance.

[0080] However, Comparative Example 1 used heat-sensitive polyvinyl chloride, which would decompose at granulation and mixing temperatures above 200°C, thus reducing the heat resistance and anti-sticking properties of the resulting material. Secondly, Comparative Example 2 used other heat-resistant additives (heat-resistant additives without the structure shown in Formula (I)), which could not improve the thermal stability of the anti-sticking agent, thus reducing the heat resistance and anti-sticking properties of the resulting material. Furthermore, Comparative Example 3 used excessively high granulation and mixing temperatures, which were detrimental to the mixing of polyethylene, heat-resistant additives, and anti-sticking agents, thus reducing the heat resistance and anti-sticking properties of the resulting material.

[0081] In summary, the method for manufacturing polyolefin materials of the present invention utilizes specific polyolefins, specific heat-resistant additives, and specific weight ratios of heat-resistant additives and anti-sticking agents, and processes them at specific temperatures to obtain polyolefin materials with anti-sticking and heat resistance.

[0082] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

[0083] [Symbol Explanation]

[0084] 100: Method

[0085] 110, 120, 130: Operation.

Claims

1. A method for producing a polyolefin-based material, characterized by, Include: Provides polyolefin material compositions, comprising: 100 parts by weight of a polyolefin, wherein the polyolefin is polyethylene or polypropylene; 0.1 to 0.9 parts by weight of a heat-resistant additive, wherein the heat-resistant additive has a first additive with the structure shown in formula (I-1) and a second additive with the structure shown in formula (I-2): (I-1) In formula (I-1), R 21 and R 41 each independently represent a methyl group or an ethyl group, R 31 represents a 1-methylpentadecyl group; and (I-2) In formula (I-2), R 22 and R 32 each independently represent a methyl group, an ethyl group or a branched alkyl group having 3 to 4 carbons, R 42 represents a linear alkyl group having 15 to 18 carbons; The weight ratio of the first additive to the second additive is 3 to 5; and 0.1 to 0.9 parts by weight of an anti-adhesive, wherein the anti-adhesive has repeating units as shown in formula (II-1) or formula (II-2): (I-1); (II-1); (III-1); (IV-1); (I-2) In formulas (II-1) and (II-2), R5 represents a hydrogen atom or a methyl group, R6 represents a straight-chain, branched, or cyclic alkyl or ester group having 3 to 18 carbon atoms, or an aromatic or heteroaryl group having 5 to 12 carbon atoms, and R7 represents -COOR' or -CONR”H, where R' and R” represent betaine, sulfobetaine, or carboxybetaine, R8 represents a hydrogen atom or a carboxyl group, where when R8 represents a hydrogen atom, R9 represents -COOR' or -CONR”H, and when R8 represents a carboxyl group, R9 represents a cationic group, p represents an integer from 5 to 120, q represents an integer from 5 to 120, and * represents a bond. The weight ratio of the heat-resistant additive to the anti-adhesion agent is 0.5 to 2. The polyolefin material composition is subjected to a mixing step at 100°C to 120°C to obtain a mixture; and The mixture is subjected to granulation and compounding processes at 200°C to 240°C to obtain the polyolefin material.

2. The method of producing a polyolefin-based material according to claim 1, characterized by, The melt index of this polyethylene is 0.20 g / 10min to 0.30 g / 10min.

3. The method of producing a polyolefin-based material according to claim 1, characterized by, The melt index of this polypropylene is 1.5 g / 10 min to 2.5 g / 10 min.

4. The method of producing a polyolefin-based material according to claim 1, characterized by, The melting point of the second additive is 50°C to 55°C.

5. The method of producing a polyolefin-based material according to claim 1, characterized by, R9 represents the cationic group as N,N-dimethylammonium ethylamino vinyl, N,N-dimethylammonium propylamino vinyl, N,N-dimethylammonium butylamino vinyl, and N,N-dimethylammonium pentylamino vinyl.

6. The method of producing a polyolefin-based material according to claim 1, characterized by, The ester group represented by R6has a structure of -COOR a a represents a linear, branched or cyclic alkyl group having a carbon number of 3 to 18, or an aromatic or heteroaromatic group having a carbon number of 5 to 12.​ 7. The method of producing a polyolefin-based material according to claim 1, characterized by, This manufacturing method excludes the application of the anti-adhesion agent to the surface of the polyolefin material.

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