Method for one-step forming of a container seal and vulcanizing machine for producing a container seal

Abstract

The application provides a one-time forming method of a container sealing strip, and comprises the following steps: S1, mixing; S2, injection and vulcanization forming; injection is performed through an injection nozzle, so that the rubber compound flows into a constant temperature runner device through a main runner, and is transported into a plurality of injection nozzles arranged in a constant temperature runner heat insulation plate through the constant temperature runner device, multi-point injection is realized, and the rubber compound is input into a mold of a vulcanizing machine through the injection nozzle, and vulcanization forming is performed; and S3, detection and packaging. The rubber compound with better fluidity is prepared, injection is performed through an injection cylinder, the rubber compound flows into a constant temperature runner device through a main runner, and is transported into a plurality of injection nozzles arranged in a constant temperature runner heat insulation plate through the constant temperature runner device, multi-point injection is realized, the rubber compound is heated at 150 DEG C to 170 DEG C, and one-time vulcanization is performed, so that the integrally formed container sealing strip is obtained; the process flow is greatly simplified, the production cost is reduced, and the product quality is improved.

Description

Technical Field

[0001] This invention belongs to the field of sealing strip processing and forming technology, and specifically relates to a one-time forming method for container sealing strips. Background Technology

[0002] Container sealing strips are used to seal containers and ensure their airtightness during transportation, preventing the entry of moisture, dust, and other external factors.

[0003] Most existing container sealing strips adopt a two-stage vulcanization molding process. The two-stage vulcanization molding process includes extrusion, cutting, vulcanization, secondary cutting, vulcanization jointing, inspection, and packaging for shipment. During the primary vulcanization, the degree of vulcanization reaches 70%-80%, leaving more than 20%-30% unvulcanized. Secondary vulcanization is carried out at the corners of the sealing strip to ensure that it is vulcanized and bonded together with the joint rubber material to form an integral mold.

[0004] It has the following defects: complex production process, many quality control points; unstable quality, high production cost, and easy breakage at the corner joint of the container sealing strip.

[0005] Patent publication number CN209533958U discloses a sealing strip vulcanization system, including a primary vulcanization mechanism and a secondary vulcanization mechanism. When the sealing strip passes through the primary vulcanization mechanism, the primary vulcanization mechanism vulcanizes and cures the sealing strip. When the sealing strip passes through the secondary vulcanization mechanism, the secondary vulcanization mechanism vulcanizes the sealing strip, thereby giving the sealing strip excellent flexibility, longer service life, and excellent cold and heat resistance. However, the above method cannot guarantee the strength of the corner joints of the sealing strip, making it prone to breakage. Summary of the Invention

[0006] In view of the problems existing in the background art, the present invention provides a method for one-time molding of container sealing strips, including the following steps:

[0007] S1, mixing;

[0008] S2, injection molding, vulcanization molding

[0009] ① Set the vulcanization parameters for the container sealing strip using a vulcanizing machine;

[0010] ② Injection is performed through several injection cylinders; the rubber compound flows into the thermostatic flow channel device through the main channel, and is then transported by the thermostatic flow channel device to multiple sets of injection nozzles located within the thermostatic flow channel heat insulation plate, achieving multi-point injection.

[0011] It is injected into the mold of the vulcanizing machine through the injection nozzle;

[0012] ③ The rubber compound is heated and vulcanized at 150℃-170℃ to obtain an integrally molded container sealing strip;

[0013] The adhesive used in step S1 includes:

[0014] Mixed A-stage:

[0015] 100 parts EPDM rubber, 2.5 parts activator, 1 part activator, 2 parts flow aid, 2 parts dispersant, 8.33 parts desiccant, 140 parts reinforcing agent; 70 parts rubber plasticizer, 60 parts filler.

[0016] Mixing Section B:

[0017] Add the following to the A-section mixed rubber: 1.2 parts rubber vulcanizing agent, 2.7 parts pre-vulcanization accelerator, 0.5 parts post-vulcanization accelerator, and 0.6 parts crosslinking delay agent E / C-80.

[0018] Optional, pre-vulcanization accelerators include:

[0019] 0.9 parts of N-cyclohexyl-2-benzothiazole sulfenamide (CZ-80).

[0020] 0.7 parts of zinc dibutyldithiocarbamate (BZ-75).

[0021] 0.7 parts of tetramethylthiuram disulfide (TT-80).

[0022] 0.4 parts ethyl thiourea.

[0023] Optionally, the activator is zinc oxide (ZNO);

[0024] The activator is stearic acid (St / Acid);

[0025] The flow aid is zinc dibenzyl dithiocarbamate (DH).

[0026] The dispersing agent is polyethylene glycol 4000 (PNG4000).

[0027] The dehumidifier is calcium oxide (ANFOGEN #200).

[0028] The reinforcing agent is carbon black (N550);

[0029] The rubber plasticizer is PB7106;

[0030] The filler is calcium carbonate (CaCO3).

[0031] The rubber vulcanizing agent in section B is sulfur (S-80).

[0032] The accelerator for the post-vulcanization stage is dithiodimorpholine (DTDM-80).

[0033] The crosslinking delay agent is benzenesulfonamide (E / C-80).

[0034] Optionally, the mixing process includes the following steps:

[0035] ① Mixing Section A:

[0036] First, put 100 parts of EPDM rubber into a mixer and masticate for 30 seconds;

[0037] Then, add 2.5 parts of activator (Zno), 1 part of activator, 2 parts of dispersant, 2 parts of flow aid, 2 parts of dispersant, 8.33 parts of desiccant, 140 parts of reinforcing agent, 70 parts of rubber plasticizer, and 60 parts of filler in sequence and mix at a mixing temperature of 140°C-150°C for 450-480 seconds.

[0038] Obtain the A-section compound rubber;

[0039] ②Mixing Section B:

[0040] First, the A-section mixed rubber is put into the internal mixer;

[0041] Then, 1.2 parts of rubber vulcanizing agent, 0.9 parts of N-cyclohexyl-2-benzothiazole sulfenamide (CZ-80), 0.7 parts of zinc dibutyldithiocarbamate (BZ-75), 0.7 parts of tetramethylthiuram disulfide (TT-80), 0.4 parts of ethylidene thiourea, 0.5 parts of the post-vulcanization accelerator dithiodimorpholine, and 0.6 parts of crosslinking retarder are added sequentially. The mixture is then kneaded at 80°C-100°C for 120 seconds to obtain...

[0042] Section B compound rubber.

[0043] A vulcanizing machine for producing container sealing strips includes:

[0044] Raising the roof beam;

[0045] The upper heating assembly is installed on the upper beam, and

[0046] An injection cylinder used to inject rubber compound into the cavity of a mold, and

[0047] Installed on the upper beam; and

[0048] The injection cylinders are located on the center line of the upper beam end face, away from the upper heating assembly;

[0049] Lower beam;

[0050] The lower heating assembly is installed on the lower beam;

[0051] Thermostatic flow channel device, and

[0052] The thermostatic flow channel insulation plate is connected to the thermostatic flow channel device; and

[0053] The constant temperature flow channel heat insulation plate is equipped with multiple sets of injection nozzles.

[0054] The distance between two adjacent sets of injection nozzles is 200-300mm.

[0055] Optionally, the injection nozzle includes a flow channel for injecting rubber compound into the mold cavity, and

[0056] The diameter of the diversion channel is 3mm-5mm.

[0057] Optionally, the injection nozzle further includes a cooling chamber.

[0058] The cooling chamber is filled with cooling oil, and

[0059] Used to wrap the branch channel.

[0060] Optionally, the upper beam, the upper heat-insulating manganese plate, and the constant temperature flow channel device are provided with injection ports for the injection cylinder to extend into.

[0061] The main channel for delivering the adhesive material to the injection nozzle within the thermostatic flow channel insulation plate.

[0062] Optionally, the upper heating assembly includes an upper heat-insulating manganese plate; and

[0063] An upper heating plate is provided on the end face of the constant temperature flow channel insulation plate away from the upper insulation manganese plate, and

[0064] The upper heating plate is connected to the upper heat-conducting plate;

[0065] The lower heating assembly includes a lower heat-conducting plate, and

[0066] A mold is provided on the lower heat-conducting plate.

[0067] A lower heating plate is provided on the end face of the lower heat-conducting plate located away from the mold position, and

[0068] The lower heating plate is connected to the lower heat-insulating manganese steel plate.

[0069] Optionally, the vulcanizing machine is 2500-3200mm long and 1200-2000mm wide, and is equipped with 4-8 columns with a diameter of 110mm-120mm.

[0070] In summary, the beneficial effects of this invention are:

[0071] (1) The present invention prepares a rubber compound with better fluidity and injects it through several injection cylinders of a vulcanizing machine, so that the rubber compound flows into the constant temperature flow channel device through the main channel and is transported to the injection nozzle through the constant temperature flow channel device, thereby realizing multi-point injection, so that the rubber compound is heated between 150℃ and 170℃ and vulcanized once, thus obtaining an integrally formed container sealing strip; thereby improving the overall performance of the container sealing strip and preventing breakage at the corner of the container sealing strip.

[0072] (2) This invention greatly simplifies the process flow, reduces production costs by 72%, and improves product quality. Attached Figure Description

[0073] Figure 1 This is a flowchart of an embodiment of the container sealing strip one-time molding method of the present invention;

[0074] Figure 2 This is a schematic diagram of the overall structure of a vulcanizing machine for producing container sealing strips according to an embodiment of the present invention;

[0075] Figure 3 This is a schematic diagram of the working surface structure of an embodiment of the vulcanizing machine for producing container sealing strips according to the present invention;

[0076] Figure 4 For the present invention Figure 1 Schematic diagram of the injection nozzle structure;

[0077] Figure 5 A flowchart of the traditional container production process;

[0078] Figure 6 This is a flowchart of the container production process in this embodiment of the present invention.

[0079] Figure label:

[0080] 100. Vulcanizing machine;

[0081] 1011. Lower pressure plate; 1012. Upper heat-insulating manganese steel plate; 1013. Constant temperature flow channel device; 1014. Constant temperature flow channel heat insulation plate; 1015. Upper heating plate; 1016. Upper heat-conducting plate; 1017. Lower heat-conducting plate; 1018. Lower heating plate; 1019. Lower heat-insulating manganese steel plate;

[0082] 10. Injection cylinder;

[0083] 20. Injection nozzle; 201. Flow channel; 202. Cooling chamber;

[0084] 30. Mold;

[0085] 40. Raising the beam;

[0086] 50. Lower beam;

[0087] 70. Mainstream Road. Detailed Implementation

[0088] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Although exemplary embodiments are disclosed in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to facilitate a thorough understanding of the present invention and to fully convey the inventive concept to those skilled in the art.

[0089] In the description of this specification, the references to terms such as "certain embodiments," "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0090] In this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0091] As is well known, during the vulcanization of rubber compounds, excessively high temperatures can easily cause scorching, while excessively low temperatures result in poor fluidity.

[0092] The container sealing strip is 3 meters long and 1.5 meters wide; its large size makes it difficult for the rubber compound to be evenly filled into the mold during the vulcanization process using a flatbed pressure vulcanizing machine. When filling the latter half, the rubber compound in the former half has already undergone vulcanization, thus affecting the performance of the container sealing strip. Therefore, the rubber compound needs to meet the vulcanization conditions and be able to fully cross-link at a certain temperature to ensure the performance of the rubber sealing strip; at the same time, it needs to have a certain degree of fluidity so that the rubber compound can be fully and evenly filled into the entire mold without premature cross-linking and scorching. For solutions to the above technical problems, please refer to [link to relevant documentation]. Figures 1-4 As shown, this embodiment provides a method for one-time molding of container sealing strips, including the following steps:

[0093] S1, mixing;

[0094] S2, injection molding, vulcanization molding

[0095] ① Set the vulcanization parameters for the container sealing strip using a vulcanizing machine;

[0096] ② Injection is performed through several injection cylinders; the rubber compound flows into the thermostatic flow channel device through the main channel, and is then transported by the thermostatic flow channel device to multiple sets of injection nozzles located within the thermostatic flow channel heat insulation plate, achieving multi-point injection.

[0097] It is injected into the mold of the vulcanizing machine through the injection nozzle;

[0098] ③ The rubber compound is heated and vulcanized at 150℃-170℃ to obtain an integrally molded container sealing strip;

[0099] S3. Inspection and packaging: Finally, the one-piece molded container sealing strip is inspected, packaged, and stored in the warehouse.

[0100] The adhesive used in step S1 includes:

[0101] Mixed A-stage:

[0102] 100 parts EPDM rubber, 2.5 parts activator, 1 part activator, 2 parts flow aid, 2 parts dispersant, 8.33 parts desiccant, 140 parts reinforcing agent; 70 parts rubber plasticizer, 60 parts filler.

[0103] Mixing Section B:

[0104] Add the following to the A-section mixed rubber: 1.2 parts rubber vulcanizing agent, 2.7 parts pre-vulcanization accelerator, 0.5 parts post-vulcanization accelerator, and 0.6 parts crosslinking delay agent E / C-80.

[0105] Most existing container sealing strips are formed through secondary vulcanization. During the primary vulcanization, the vulcanization degree reaches 70%-80%, leaving 20%-30% or more unvulcanized. Secondary vulcanization is then performed at the corners of the sealing strip to ensure co-vulcanization and bonding with the joint rubber material for integrated molding. In this embodiment, a more fluid rubber material is prepared and injected through several injection cylinders 10 of the vulcanizing machine. The rubber material flows through the main channel 70 into multiple sets of injection nozzles 20 located within the constant temperature flow channel heat insulation plate 1014, achieving multi-point injection. This allows the rubber material to be heated between 150℃ and 170℃ for primary vulcanization, resulting in an integrated container sealing strip. This significantly simplifies the process, reduces production costs, and improves product quality.

[0106] Please see Figure 2 , 3 As shown in Figure 4, this embodiment provides a vulcanizing machine 100 for producing container sealing strips. The vulcanizing machine 100 is 2500mm-3200mm long and 1200mm-2000mm wide. To improve stability, the vulcanizing machine 100 is provided with 4-8 columns with a diameter of 110mm-120mm. The vulcanizing machine 100 includes an upper beam 40 and an upper heating assembly disposed on the upper beam 40. The vulcanizing machine 100 also includes a lower beam 50 disposed opposite to the upper beam 40 and a lower heating assembly disposed on the lower beam 50.

[0107] The upper beam 40 is provided with an injection cylinder 10 for injecting rubber mixture into the cavity of the mold 30. The injection cylinder 10 is located on the center line of the end face of the upper beam away from the upper heating assembly.

[0108] The upper heating assembly includes an upper heat-insulating manganese plate 1012, and a constant temperature flow channel device 1013 is provided on the end face of the upper heat-insulating manganese plate 1012 at a position away from the upper beam 40. The constant temperature flow channel device 1013 also includes a constant temperature flow channel heat insulation plate 1014, and an upper heating plate 1015 is provided on the end face of the constant temperature flow channel heat insulation plate 1014 away from the upper heat-insulating manganese plate 1012. The heating assembly also includes an upper heat-conducting plate 1016 connected to the upper heating plate 1015.

[0109] The upper beam 40, the upper heat insulation manganese plate 1012, and the constant temperature flow channel device 1013 are provided with a main flow channel 70 for the injection port of the injection cylinder 10 to extend into; the adhesive is injected into the constant temperature flow channel heat insulation plate 1014 through the main flow channel 70.

[0110] Furthermore, the constant temperature flow channel insulation plate is provided with multiple component flow channels 201, with an interval of 200-300mm between two adjacent component flow channels 201; and a diameter of 3mm-5mm.

[0111] The embodiment provides several injection cylinders located on the centerline of the upper beam end face away from the upper heating component, and equipped with multi-component flow channels 201 with a spacing of 200mm-300mm. This ensures that the rubber compound can be uniformly filled into the cavity of the mold 30, reducing the probability of curing and preventing the situation where the rubber compound in the first half has already undergone a vulcanization reaction when the second half of the filling is completed, thus improving the performance of the container sealing strip. At the same time, the air in the mold cavity is discharged by high-pressure extrusion through the flow channels 201 with a diameter of 3mm-5mm.

[0112] Furthermore, the lower heating assembly includes a lower heat-conducting plate 1017, and a mold 30 is provided on the lower heat-conducting plate 1017, and an oil cylinder for mold opening is provided on one side. A lower heating plate 1018 is provided on the end face of the lower heat-conducting plate 1017 away from the mold 30, and the lower heating plate 1018 also includes a lower heat-insulating manganese steel plate 1019.

[0113] In this embodiment, by using several injection cylinders positioned on the centerline of the upper beam end face away from the upper heating component, and in conjunction with multi-component flow channels 201 spaced 200mm-300mm apart, the flow distance can be reduced, improving the rapid flow of the rubber compound into the mold cavity. However, in practical applications, to ensure that the rubber compound can be uniformly filled into the mold cavity 30, the injection temperature needs to be set above 70°C. Existing rubber compounds, when plasticized at 70°C, will prematurely undergo shallow cross-linking, causing scorching. Therefore, to enable the container sealing strip to be molded in one step and possess good performance, the rubber compound needs to have a certain degree of fluidity and not cause scorching at temperatures above 70°C. To address these technical problems, please refer to [link to relevant documentation]. Figure 1-4 As shown, the optimal ratio is obtained by mixing different proportions of the ingredients in the formula.

[0114] Pre-vulcanization accelerators include:

[0115] 0.9 parts of N-cyclohexyl-2-benzothiazole sulfenamide (CZ-80).

[0116] 0.7 parts of zinc dibutyldithiocarbamate (BZ-75).

[0117] 0.7 parts of tetramethylthiuram disulfide (TT-80).

[0118] 0.4 parts ethyl thiourea (NA-22).

[0119] The activator is stearic acid (St / Acid);

[0120] The flow aid is zinc dibenzyl dithiocarbamate (DH).

[0121] The dispersing agent is polyethylene glycol 4000 (PNG4000).

[0122] The dehumidifier is calcium oxide (ANFOGEN #200).

[0123] The activator is zinc oxide (ZNO);

[0124] The reinforcing agent is carbon black (N550);

[0125] The rubber plasticizer is PB7106;

[0126] The filler is calcium carbonate (CaCO3).

[0127] The rubber vulcanizing agent in section B is sulfur (S-80).

[0128] The accelerator for the post-vulcanization stage is dithiodimorpholine (DTDM-80).

[0129] The crosslinking delay agent is benzenesulfonamide (E / C-80).

[0130] The mixing process includes the following steps:

[0131] ① Mixing Section A:

[0132] First, put 100 parts of EPDM rubber into a mixer and masticate for 30 seconds;

[0133] Then, add 2.5 parts of activator (Zno), 1 part of activator, 2 parts of dispersant, 2 parts of flow aid, 2 parts of dispersant, 8.33 parts of desiccant, 140 parts of reinforcing agent, 70 parts of rubber plasticizer, and 60 parts of filler in sequence and mix at a mixing temperature of 140°C-150°C for 450-480 seconds.

[0134] Obtain the A-section compound rubber;

[0135] ②Mixing Section B:

[0136] First, the A-section mixed rubber is put into the internal mixer;

[0137] Then, 1.2 parts of rubber vulcanizing agent, 0.9 parts of N-cyclohexyl-2-benzothiazole sulfenamide (CZ-80), 0.7 parts of zinc dibutyldithiocarbamate (BZ-75), 0.7 parts of tetramethylthiuram disulfide (TT-80), 0.4 parts of ethylidene thiourea (NA-22), 0.5 parts of post-vulcanization accelerator dithiodimorpholine, and 0.6 parts of crosslinking retarder are added sequentially. The mixture is then mixed at 80°C-100°C for 120 seconds to obtain the B-section compound.

[0138] The following example illustrates the key points of formulation design: By adding 1.2 parts of vulcanizing agent S-80 to the B stage of mixing, both the vulcanization requirements of the rubber compound and process safety are met; by adding 0.5 parts of downstream accelerator DTDM-80 to enhance the downstream vulcanization of the rubber compound, the pursuit of vulcanization performance and process safety are balanced; by adding 0.6 parts of crosslinking delay agent E / C-80, the rubber compound will not crosslink at 70°C, and at the same time, the crosslinking speed is slowed down during the flow in the mold at 150°C-170°C, so as to meet the requirement of vulcanization and molding after the rubber compound flows into the mold and fills the mold.

[0139] In this embodiment, different amounts of vulcanizing agent S-80 are added;

[0140] Objective: To determine the optimal dosage in the formula.

[0141] Table 1 shows 1-5 comparative examples containing different amounts of vulcanizing agent S-80 in the B stage of the compounding process:

[0142] Comparative Example 1 2 3 4 5 Vulcanizing agent (S-80) 0.8 copies 1.0 copy 1.2 portions 1.4 copies 1.6 copies

[0143] Comparative Examples 1-5 are comparative tests of the effect of changes in the amount of vulcanizing agent on the physical properties of the rubber compound; the amounts of other raw materials and the processing technology remain unchanged. (Excluding accelerator DTDM-80 and crosslinking delay agent E / C-80)

[0144] The data in Table 1.1 are the verification results of test pieces 1-5 in Table 1:

[0145] Comparative Example 1 2 3 4 5 Vulcanization pressure (Kg / cm2) 170 170 170 170 170 Vulcanization temperature (°C) 165 165 165 165 165 Tensile strength (MPa) 8 8.5 9.5 9.7 9.2 Elongation at break (%) 350 360 420 350 302 Mooney viscosity (ML100-4) 65 68 72 75 82

[0146] When the amount of vulcanizing agent S-80 used was determined to be 1.2 parts, the tensile strength was 9.5 MPa, the elongation at break was 420%, and the overall performance was optimal (the optimal amount of vulcanizing agent S-80 used was determined to be 1.2 parts).

[0147] In this embodiment, tests were conducted by adding different amounts of the post-process accelerator DTDM-80 (1-5 parts) to determine the optimal dosage in the formulation.

[0148] Comparative examples of accelerator DTDM-80 in Table 2:

[0149] Example 1 2 3 4 5 Post-stage accelerator (DTDM-80) 0.1 copies 0.3 copies 0.5 copies 0.7 copies 0.9 copies

[0150] Comparative Examples 1-5 are comparative tests on the effect of changes in the amount of the downstream accelerator DTDM-80 on the physical properties of the rubber compound; the amounts of other raw materials and the processing technology remain unchanged. (These are comparative tests based on the determination of 1.2 parts of vulcanizing agent S-80 in Table 1).

[0151] The data in Table 2.1 are the verification results of test pieces 1-5 in Table 2:

[0152] Comparative Example 1 2 3 4 5 Vulcanization pressure (Kg / cm2) 170 170 170 170 170 Vulcanization temperature (°C) 170 170 170 170 170 Tensile strength (MPa) 8.3 9 10 9.5 8.5 Elongation at break (%) 362 395 430 380 302 Mooney viscosity (ML100-4) 68.5 69.2 72 76 81

[0153] When the amount of downstream accelerator DTDM-80 used was determined to be 0.5 parts, the tensile strength was 10 MPa and the elongation at break was 430%, which showed the best overall performance. Therefore, the optimal usage amount was determined to be 0.5 parts of downstream accelerator (DTDM-80).

[0154] At this time, the Mooney viscosity is 72ML100-4, which does not meet the requirements of the one-time injection vulcanization process for container sealing strips.

[0155] Therefore, in this embodiment, different amounts of crosslinking delay agent (E / C-80) are added;

[0156] Objective: To determine the optimal dosage in the formula.

[0157] Table 3 shows the dosage of crosslinking delay agent (E / C-80) in Examples 1-5:

[0158] Example 1 2 3 4 5 Crosslinking delay agent (E / C-80) 0.2 copies 0.4 copies 0.6 copies 0.8 copies 1.0 copy

[0159] Examples 1-5 represent variations in the amount of crosslinking retarder E / C-80, while the amounts of other raw materials and the processing technology remain unchanged. (These are comparative tests based on the 1.2 parts of vulcanizing agent S-80 determined in Table 1; and comparative tests based on the 0.5 parts of downstream accelerator DTDM-80 determined in Table 2.)

[0160] Table 3.1 shows the verification results of the test pieces in Examples 1-5 of Table 3:

[0161] Comparative Example 1 2 3 4 5 Vulcanization pressure (Kg / cm2) 170 170 170 170 170 Vulcanization temperature (°C) 170 170 170 170 170 Tensile strength (MPa) 8.3 9 10.5 8.9 8.1 Elongation at break (%) 362 395 442 454 462 Mooney viscosity (ML100-4) 70.2 65.4 60.5 60.2 58.6

[0162] When the amount of crosslinking delay agent used is 0.6 parts: the tensile strength is 10.5 MPa, the elongation at break is 442%, and the Mooney viscosity is 65, which is the best overall performance; therefore, the optimal amount of crosslinking delay agent (E / C-80) is determined to be 0.6 parts.

[0163] In this embodiment, experiments revealed the following physical properties of the sample: tensile strength 10.5 MPa, elongation at break 442%. This indicates that the formulation achieves optimal overall performance, fully meeting the physical property requirements for container sealing strips; the Mooney viscosity of 60.5 mL 100-4 fully meets the requirements of the injection molding process.

[0164] Table 4 shows the performance test results of the container sealing strips in Examples 1-5:

[0165]

[0166] Mooney viscosity is an indicator used to measure the flowability of rubber compounds at a specific temperature. The higher the Mooney viscosity, the worse the flowability; conversely, the lower the Mooney viscosity, the better the flowability.

[0167] As shown in Table 3.1, adding 0.5 parts of accelerator (DTDM-80) improved the physical properties of the rubber compound, thus meeting the physical performance requirements of the container sealing strip. Furthermore, adding 0.6 parts of crosslinking retarder (E / C80) extended the crosslinking time, reduced the Mooney viscosity, and met the injection vulcanization production process requirements for the one-time molding of the container sealing strip.

[0168] As can be seen from the data in Table 4, the physical properties of container sealing strips produced by injection vulcanization in one step are far superior to those of container sealing strips produced by the existing traditional process of secondary corner vulcanization.

[0169] In this embodiment, the present invention prepares a more fluid rubber compound and injects it through several injection cylinders of a vulcanizing machine. The rubber compound flows through a main channel into multiple sets of injection nozzles located within a constant-temperature flow channel heat insulation plate, achieving multi-point injection. This allows the rubber compound to be heated between 150℃ and 170℃ and vulcanized once, resulting in an integrally molded container sealing strip. Furthermore, by... Figure 5 and Figure 6 A comparison reveals that this embodiment significantly simplifies the process and reduces production costs by 72%.

[0170] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to impose specific limitations. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for one-time molding of container sealing strips, characterized in that, Includes the following steps: S1, mixing; S2, injection molding, vulcanization molding ① Set the vulcanization parameters for the container sealing strip using a vulcanizing machine; ② Injection is performed through several injection cylinders; the rubber material flows into the constant temperature runner device through the main channel, and is then transported through the constant temperature runner device to multiple sets of injection nozzles set in the constant temperature runner heat insulation plate to achieve multi-point injection, and is then input into the mold of the vulcanizing machine through the injection nozzles. ③ The rubber compound is heated and vulcanized at 150℃-170℃ to obtain an integrally molded container sealing strip; The adhesive used in step S1 includes: Mixed A-stage: 100 parts EPDM rubber, 2.5 parts activator, 1 part activator, 2 parts flow aid, 2 parts dispersant, 8.33 parts desiccant, 140 parts reinforcing agent; 70 parts rubber plasticizer, 60 parts filler; Mixing Section B: Add the following to the A-section mixed rubber: 1.2 parts rubber vulcanizing agent, 2.7 parts pre-vulcanization accelerator, 0.5 parts post-vulcanization accelerator, and 0.6 parts crosslinking retarder. Pre-vulcanization accelerators include: 0.9 parts of N-cyclohexyl-2-benzothiazole sulfenamide, 0.7 parts of zinc dibutyldithiocarbamate, 0.7 parts of tetramethylthiuram disulfide, 0.4 parts ethyl thiourea; The rubber vulcanizing agent in section B is sulfur. The accelerator for the later stage of vulcanization is dithiodimorpholine; The crosslinking delay agent is benzenesulfonamide.

2. The method for one-time forming of container sealing strips according to claim 1, characterized in that, The activator is zinc oxide; The activator is stearic acid; The flow aid is zinc dibenzyl dithiocarbamate; The dispersing agent is polyethylene glycol 4000; The dehumidifier is calcium oxide; The reinforcing agent is carbon black; The filler is calcium carbonate.

3. The method for one-time forming of container sealing strips according to claim 1, characterized in that, The mixing process in step S1 includes: ① Mixing Section A: First, put 100 parts of EPDM rubber into a mixer and masticate for 30 seconds; Then, add 2.5 parts of activator, 1 part of activator, 2 parts of flow aid, 2 parts of dispersant, 8.33 parts of desiccant, 140 parts of reinforcing agent, 70 parts of rubber plasticizer, and 60 parts of filler in sequence and mix at a mixing temperature of 140°C-150°C for 450-480 seconds. Obtain the A-section compound rubber; ②Mixing Section B: First, the A-section mixed rubber is put into the internal mixer; Then, 1.2 parts of rubber vulcanizing agent, 0.9 parts of N-cyclohexyl-2-benzothiazole sulfenamide, 0.7 parts of zinc dibutyldithiocarbamate, 0.7 parts of tetramethylthiuram disulfide, 0.4 parts of ethylidene thiourea, 0.5 parts of the post-vulcanization accelerator dithiodimorpholine, and 0.6 parts of crosslinking retarder are added sequentially. The mixture is then mixed at 80°C-100°C for 120 seconds to obtain the B-section compound.

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