Supercritical extrusion antibacterial PET foam and preparation method thereof

Abstract

The invention relates to the technical field of high polymer materials, in particular to supercritical extrusion antibacterial PET foam and a preparation method thereof. Comprising PET resin, an antibacterial agent, a foaming agent and an auxiliary agent, the method comprises the following steps: drying PET resin; premixing the antibacterial agent, the foaming agent and the auxiliary agent; adding the dried PET resin and the premixed antibacterial agent, foaming agent and assistant into a double-screw extruder, and carrying out melt blending at 250-300 DEG C to obtain an antibacterial PET blend; the antibacterial PET blend is subjected to extrusion granulation, and antibacterial PET particles are obtained; putting the antibacterial PET particles in an extrusion foaming process, and heating and foaming at the temperature of 150-200 DEG C to form a foam blank; curing treatment and drying treatment are conducted on the foam blank, the antibacterial PET foam is obtained, growth and reproduction of various common bacteria can be effectively inhibited, and the strict requirements of many fields for the antibacterial performance of materials are met.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a supercritical extrusion antibacterial PET foam and its preparation method. Background Technology

[0002] PET foam is widely used in construction, furniture, and automotive industries due to its excellent physical and chemical properties, such as light weight, high strength, chemical resistance, and thermal and sound insulation. However, traditional PET foam preparation methods have some limitations, such as foaming agent residue, uneven cell structure, and high cost. Supercritical fluid technology, as a novel foaming technology, has advantages such as being non-toxic, pollution-free, and producing uniform foaming, providing a new approach for preparing high-performance PET foam. Furthermore, with increasing demands for hygiene and health, and stringent requirements for antibacterial properties in specific applications, this technology is particularly relevant.

[0003] However, due to the lack of antibacterial properties, existing PET foam materials are limited in many fields and cannot meet the stringent requirements for antibacterial performance in fields closely related to daily life, such as construction, furniture, and automobiles. Summary of the Invention

[0004] The purpose of this invention is to provide a supercritical extrusion antibacterial PET foam and its preparation method, aiming to solve the technical problem that existing PET foam materials are limited in many fields due to the lack of antibacterial function, and cannot meet the strict requirements for antibacterial performance of materials in fields closely related to daily life such as construction, furniture, and automobiles.

[0005] To achieve the above objectives, the present invention provides a supercritical extrusion antibacterial PET foam comprising 100 parts of PET resin, 8-15 parts of antibacterial agent, 2-4 parts of foaming agent, and 0.5-1.5 parts of additives.

[0006] The antibacterial agent is a compound antibacterial agent, which is composed of inorganic antibacterial agents and organic antibacterial agents, with the mass ratio of inorganic antibacterial agents to organic antibacterial agents being 1:1 to 3:1.

[0007] Among them, the inorganic antibacterial agent is one or two of silver ion antibacterial agents and titanium dioxide antibacterial agents.

[0008] Among them, organic antibacterial agents are one or two of quaternary ammonium salt antibacterial agents and imidazole antibacterial agents.

[0009] The foaming agent is one or a mixture of two of the following: chemical foaming agents and physical foaming agents. The chemical foaming agents are azodicarbonamide and sodium bicarbonate, and the physical foaming agents are carbon dioxide and nitrogen.

[0010] This invention also provides a method for preparing supercritical extruded antibacterial PET foam, comprising the following steps: The PET resin is dried to remove moisture. The antibacterial agent, foaming agent, and additives are premixed; The dried PET resin, along with premixed antibacterial agent, foaming agent, and additives, is added to a twin-screw extruder and melt-blended at a temperature of 250~300℃ to obtain an antibacterial PET blend. The antibacterial PET blend is extruded and granulated to obtain antibacterial PET granules; Antibacterial PET granules are placed in an extrusion foaming process and heated and foamed at a temperature of 150~200℃ to form a foam preform. The foam preform is subjected to curing and drying treatments to obtain antibacterial PET foam.

[0011] This invention discloses a supercritical extrusion antibacterial PET foam and its preparation method. The method comprises the following steps: using 100 parts PET resin, 8-15 parts antibacterial agent, 2-4 parts foaming agent, and 0.5-1.5 parts additives; drying the PET resin to remove moisture; premixing the antibacterial agent, foaming agent, and additives; adding the dried PET resin and the premixed antibacterial agent, foaming agent, and additives to a twin-screw extruder and melt-blending at 250-300°C to obtain an antibacterial PET blend; and extruding and granulating the antibacterial PET blend. Antibacterial PET granules are obtained; the antibacterial PET granules are placed in an extrusion foaming process and heated and foamed at a temperature of 150~200℃ to form a foam preform; the foam preform is then subjected to curing and drying treatments to obtain antibacterial PET foam. In the above process, the growth and reproduction of microorganisms such as bacteria and mold can be effectively inhibited, the spread of germs can be reduced, and a more hygienic and healthy environment can be provided for people. This helps to reduce the risk of infectious diseases and improve the level of public health safety, thereby meeting the strict requirements of antibacterial properties of materials in fields closely related to daily life, such as construction, furniture, and automobiles. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart of the steps in the preparation method of supercritical extrusion antibacterial PET foam of the present invention. Detailed Implementation

[0014] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application.

[0015] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0016] It should be understood that although the terms first, second, third, etc., may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0017] This invention provides a supercritical extrusion antibacterial PET foam, comprising 100 parts of PET resin, 8-15 parts of antibacterial agent, 2-4 parts of foaming agent, and 0.5-1.5 parts of additives.

[0018] Furthermore, the antibacterial agent is a compound antibacterial agent, which is composed of inorganic antibacterial agents and organic antibacterial agents, with the mass ratio of inorganic antibacterial agents to organic antibacterial agents being 1:1 to 3:1.

[0019] Furthermore, the inorganic antibacterial agent is one or both of silver ion antibacterial agents and titanium dioxide antibacterial agents.

[0020] Furthermore, the organic antibacterial agent is one or both of quaternary ammonium salt antibacterial agents and imidazole antibacterial agents.

[0021] Furthermore, the foaming agent is one or a mixture of two of the following: a chemical foaming agent and a physical foaming agent, wherein the chemical foaming agent is azodicarbonamide and sodium bicarbonate, and the physical foaming agent is carbon dioxide and nitrogen.

[0022] Please see Figure 1 The present invention also provides a method for preparing supercritical extrusion antibacterial PET foam, comprising the following steps: S100: Drying process is performed on the PET resin to remove moisture from it; S200: Premixing antibacterial agents, foaming agents, and additives: S300: The dried PET resin, premixed antibacterial agent, foaming agent and additives are added to a twin-screw extruder and melt-blended at a temperature of 250~300℃ to obtain an antibacterial PET blend; S400: Extruding and granulating the antibacterial PET blend to obtain antibacterial PET granules; S500: Antibacterial PET granules are placed in an extrusion foaming process and heated and foamed at a temperature of 150~200℃ to form a foam preform; S600: The foam preform is cured and dried to obtain antibacterial PET foam.

[0023] In this embodiment, the PET resin is first dried to remove moisture. Then, the antibacterial agent, foaming agent, and additives are premixed. The dried PET resin is then added to a twin-screw extruder and melt-blended at 250-300°C to obtain an antibacterial PET blend. Next, the antibacterial PET blend is extruded and granulated to obtain antibacterial PET granules. These granules are then placed in an extrusion foaming process and heated at 150-200°C to form a foam preform. Finally, the foam preform is cured and dried to obtain antibacterial PET foam. This process effectively inhibits the growth and reproduction of bacteria, mold, and other microorganisms, reducing the spread of pathogens and providing a more hygienic and healthy environment. It helps reduce the risk of infectious diseases, improves public health safety, and thus meets the stringent requirements for antibacterial properties in fields closely related to daily life, such as construction, furniture, and automobiles.

[0024] Example 1: Material preparation: Weigh 100 parts PET resin, 10 parts inorganic antibacterial agent (composed of 10 parts nano silver ion antibacterial agent), 3 parts supercritical carbon dioxide foaming agent, 1 part antioxidant and 0.5 parts chain extender; Additive granulation: The dried PET resin, premixed antibacterial agent, and additives are added to a twin-screw extruder and melt-blended at 250-300°C with a screw speed of 200-400 r / min. Through the high-speed shearing and mixing action of the twin-screw extruder, the antibacterial agent and additives are uniformly dispersed in the PET resin, forming an antibacterial PET blend. The melt-blended antibacterial PET blend is extruded from the die head of the twin-screw extruder, cooled in a cooling water tank, and then granulated using a pelletizer to obtain antibacterial PET functional masterbatch. Foaming Molding: Antibacterial PET functional masterbatch is added to a twin-screw extruder and heated at 200-250℃ while a foaming agent gas (supercritical carbon dioxide) is introduced. This allows the supercritical fluid foaming agent to fully dissolve into the PET melt. The saturated PET melt is then extruded through the extruder die while rapid decompression causes the supercritical fluid foaming agent to expand rapidly, forming a foam structure. The extrusion temperature is 150-200℃, and the extrusion pressure is 0.1-1 MPa, causing the antibacterial PET granules to expand and foam, forming a foam preform. The foam preform is then cured at a specific temperature to stabilize the foam structure and improve its performance. Post-processing: The foamed material is cooled and dried to remove residual foaming agent and moisture. The drying conditions are 80~100℃ for 1~2 hours. Then, the foam is cut and processed as needed to obtain the final antibacterial PET foam product.

[0025] Example 2: Material preparation: Weigh 100 parts PET resin, 10 parts organic antibacterial agent (composed of 10 parts quaternary ammonium salt, 3 parts supercritical carbon dioxide foaming agent, 1 part antioxidant and 0.5 parts chain extender); Additive granulation: The dried PET resin, premixed antibacterial agent, and additives are added to a twin-screw extruder and melt-blended at 250-300°C with a screw speed of 200-400 r / min. Through the high-speed shearing and mixing action of the twin-screw extruder, the antibacterial agent and additives are uniformly dispersed in the PET resin, forming an antibacterial PET blend. The melt-blended antibacterial PET blend is extruded from the die head of the twin-screw extruder, cooled in a cooling water tank, and then granulated using a pelletizer to obtain antibacterial PET functional masterbatch. Foaming Molding: Antibacterial PET functional masterbatch is added to a twin-screw extruder and heated at 200-250℃ while a foaming agent gas (supercritical carbon dioxide) is introduced. This allows the supercritical fluid foaming agent to fully dissolve into the PET melt. The saturated PET melt is then extruded through the extruder die while rapid decompression causes the supercritical fluid foaming agent to expand rapidly, forming a foam structure. The extrusion temperature is 150-200℃, and the extrusion pressure is 0.1-1 MPa, causing the antibacterial PET granules to expand and foam, forming a foam preform. The foam preform is then cured at a specific temperature to stabilize the foam structure and improve its performance. Post-processing: The foamed material is cooled and dried to remove residual foaming agent and moisture. The drying conditions are 80~100℃ for 1~2 hours. Then, the foam is cut and processed as needed to obtain the final antibacterial PET foam product.

[0026] Example 3: Material preparation: Weigh 100 parts PET resin, 10 parts composite antibacterial agent (composed of 5 parts quaternary ammonium salt (ADBAC antibacterial agent) and 5 parts silver ion antibacterial agent), 3 parts supercritical carbon dioxide foaming agent, 1 part antioxidant and 0.5 parts chain extender; Additive granulation: The dried PET resin, premixed antibacterial agent, and additives are added to a twin-screw extruder and melt-blended at 250-300°C with a screw speed of 200-400 r / min. Through the high-speed shearing and mixing action of the twin-screw extruder, the antibacterial agent and additives are uniformly dispersed in the PET resin, forming an antibacterial PET blend. The melt-blended antibacterial PET blend is extruded from the die head of the twin-screw extruder, cooled in a cooling water tank, and then granulated using a pelletizer to obtain antibacterial PET functional masterbatch. Foaming Molding: Antibacterial PET functional masterbatch is added to a twin-screw extruder and heated at 200-250℃ while a foaming agent gas (supercritical carbon dioxide) is introduced. This allows the supercritical fluid foaming agent to fully dissolve into the PET melt. The saturated PET melt is then extruded through the extruder die while rapid decompression causes the supercritical fluid foaming agent to expand rapidly, forming a foam structure. The extrusion temperature is 150-200℃, and the extrusion pressure is 0.1-1 MPa, causing the antibacterial PET granules to expand and foam, forming a foam preform. The foam preform is then cured at a specific temperature to stabilize the foam structure and improve its performance. Post-processing: The foamed material is cooled and dried to remove residual foaming agent and moisture. The drying conditions are 80~100℃ for 1~2 hours. Then, the foam is cut and processed as needed to obtain the final antibacterial PET foam product.

[0027] Test Project Methods / Standards Target value Example 1 Example 2 Example 3 Antibacterial properties ISO 22196 (Escherichia coli / Staphylococcus aureus) Antibacterial rate >99% (24h) 99.8% 55.2％ 87% Antibacterial durability Post-washing / UV aging test Antibacterial rate >95% after 50 washes. 95% 50% 80% Cytotoxicity ISO 10993-5 (Extraction Method) Cell viability >80% (non-toxic) 86% 85% 86% foam structure SEM observation of bubble distribution Uniform pore size, closed-cell rate ≥90% 91% 87% 89% Mechanical properties ASTM D1621 (Compressive Strength) ≥1.5 MPa (density 0.2 g / cm³) 1.6 MPa 1.3 MPa 1.5MPa Table 1; As shown in Table 1, Example 1 has the best overall performance because nano-metal ions are relatively stable at high temperatures and can play a role in nucleation and enhancement. Organic antibacterial agents partially fail at high temperatures, affecting antibacterial and mechanical properties.

[0028] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0029] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A supercritical extruded antibacterial PET foam, characterized in that, It includes 100 parts of PET resin, 8-15 parts of antibacterial agent, 2-4 parts of foaming agent, and 0.5-1.5 parts of additives.

2. The supercritical extruded antibacterial PET foam as described in claim 1, characterized in that, The antibacterial agent is a compound antibacterial agent, which is composed of inorganic antibacterial agents and organic antibacterial agents, with the mass ratio of inorganic antibacterial agents to organic antibacterial agents being 1:1 to 3:

1.

3. The supercritical extruded antibacterial PET foam as described in claim 2, characterized in that, The inorganic antibacterial agent is one or both of silver ion antibacterial agents and titanium dioxide antibacterial agents.

4. The supercritical extruded antibacterial PET foam as described in claim 3, characterized in that, Organic antibacterial agents are one or two of quaternary ammonium salt antibacterial agents and imidazole antibacterial agents.

5. The supercritical extruded antibacterial PET foam as described in claim 4, characterized in that, The foaming agent is one or a mixture of two of the following: chemical foaming agents and physical foaming agents. The chemical foaming agents are azodicarbonamide and sodium bicarbonate, and the physical foaming agents are carbon dioxide and nitrogen.

6. A method for preparing supercritical extruded antibacterial PET foam, as described in claim 1, characterized in that, Includes the following steps: The PET resin is dried to remove moisture. The antibacterial agent, foaming agent, and additives are premixed; The dried PET resin, along with premixed antibacterial agent, foaming agent, and additives, is added to a twin-screw extruder and melt-blended at a temperature of 250~300℃ to obtain an antibacterial PET blend. The antibacterial PET blend is extruded and granulated to obtain antibacterial PET granules; Antibacterial PET granules are placed in an extrusion foaming process and heated and foamed at a temperature of 150~200℃ to form a foam preform. The foam preform is subjected to curing and drying treatments to obtain antibacterial PET foam.

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