Manufacturing method of perfluoroether rubber part

Abstract

The invention relates to the technical field of fluoroether rubber processing, in particular to a manufacturing method of a perfluoroether rubber part, which specifically comprises the following steps: placing the perfluoroether rubber part in a vulcanization mold; heating the vulcanizing mold to 80-120 DEG C, and preserving heat for more than 10 seconds, so that the perfluoroether raw rubber is preliminarily softened; continuously preserving heat, covering a vacuum cover outside the vulcanization mold in a sealing manner, and repeatedly pressing the vulcanization mold up and down while vacuumizing, so as to promote the softened perfluoroether raw rubber to flow and exhaust, fill the mold cavity and overflow; heating and vulcanizing; a cooling medium is input for rapid cooling; and cooling to 80-120 DEG C, opening the mold and taking the material. The problem of poor flowability of the perfluoroether rubber is improved by virtue of accurate segmented temperature control and mechanical action: firstly, the softening temperature of the perfluoroether rubber is set to be 80-120 DEG C, and the rubber material is softened but not vulcanized; and secondly, the softened perfluoroether raw rubber is jointly promoted to flow and exhaust by combining vacuumizing and up-and-down pressing actions of the vulcanization mold, and the mold cavity is filled with the softened perfluoroether raw rubber and overflows.

Description

Technical Field

[0001] The invention relates to the technical field of fluoroether rubber processing, and in particular to a method for manufacturing a perfluoroether rubber part. Background Art

[0002] Perfluoroether rubber has been widely used in the semiconductor and pan-semiconductor manufacturing fields due to its high-performance sealing characteristics and excellent performance. As one of the main consumables with the largest production volume in the semiconductor field, perfluoroether is mainly polymerized with tetrafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride and other monomers mentioned above but not limited to the above, and the CH bond is replaced by the CF bond, which is the most stable single bond in the known polymer long chain structure, thereby obtaining significant heat resistance, chemical resistance, plasma resistance and other properties.

[0003] However, due to its poor processing performance, perfluoroether rubber is prone to surface defects including pits, bulges and other unevenness when making finished products. Perfluoroether application scenarios will cause huge economic losses if it fails, such as the connection of semiconductor process equipment, which will have a great impact on the process yield. Summary of the invention

[0004] The purpose of the present invention is to provide a method for manufacturing perfluoroether rubber parts to solve the problem of surface defects caused by poor fluidity of perfluoroether rubber after vulcanization molding, so as to meet the problems of insufficient sealing and insufficient durability of defects caused by surface defects in high-end application industries, and meet the highest level appearance specifications of Table-1 CS of the international standard ISO-3601-3 O-ring quality acceptance standard.

[0005] To achieve the above object, the technical solution adopted by the present invention is: The method for manufacturing a perfluoroether rubber part specifically comprises the following steps: S1. The perfluoroether raw rubber obtained by mixing and extrusion is placed in a vulcanization mold, and the temperature measuring port of the vulcanization mold is located on the mold surface of the vulcanization mold; S2, heat the vulcanization mold to 80℃-120℃ and keep it warm for more than 10 seconds to make the perfluoroether raw rubber material initially soften; S3, continue to keep warm, set a vacuum cover on the outside of the vulcanization mold, and press the vulcanization mold up and down repeatedly while evacuating the vacuum, so as to promote the softened perfluoroether raw rubber to flow and exhaust, fill the mold cavity and overflow; S4, heating the vulcanization mold to the vulcanization temperature and keeping the temperature and pressure; S5. Cover the vulcanization mold with a vacuum cover, input cooling medium into the vacuum cover, and quickly cool down the vulcanization mold; S6. When the temperature of the vulcanization mold drops to 80℃-120℃, stop the cooling medium, open the vacuum cover, and then open the mold to take out the material.

[0006] Preferably, the number of times of upper and lower pressing in step S3 is 2-5 times.

[0007] Preferably, the pressing pressure in step S3 is 50 kgf / cm 2 -150kgf / cm 2 .

[0008] Preferably, the vacuum degree in step S3 is 1Pa-10kPa.

[0009] Preferably, the vulcanization pressure in step S4 is 15 MPa-20 MPa.

[0010] Preferably, the cooling medium is liquid nitrogen or dry ice.

[0011] Preferably, the cooling air supply pressure is 1MPa-1.5MPa, and the air supply flow rate is 5L / min-8L / min.

[0012] Preferably, the cooling time of step S5 is 45 seconds to 75 seconds.

[0013] Preferably, the operation duration of step S3 is 5 seconds to 10 seconds.

[0014] Preferably, when the mold is opened and the material is taken out in step S6, the vulcanization mold is kept on the heating platform of the vulcanizer.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The manufacturing method of the present invention sequentially performs two stages before the formal vulcanization reaction stage, and improves the problem of poor fluidity of perfluoroether rubber by precise segmented temperature control and mechanical action: first, the softening temperature of perfluoroether rubber is set at 80°C-120°C, and the perfluoroether rubber is softened but does not produce a vulcanization reaction by heat preservation treatment in this stage; second, a vacuum hood is used to create a vacuum-sealed environment outside the vulcanization mold, and the vacuuming and upper and lower pressing actions of the vulcanization mold are combined to promote the softened perfluoroether raw rubber to flow and exhaust, fill the mold cavity and overflow, so as to achieve a full product shape, improve the problem of poor fluidity, and solve the problem of surface defects of perfluoroether rubber caused by poor fluidity after vulcanization molding, so as to meet the problems of insufficient sealing and insufficient durability of defects caused by surface defects in high-end application industries, and meet the highest level appearance specifications of Table-1 CS of the international standard ISO-3601-3 O-ring quality acceptance standard.

[0016] In addition, after the vulcanization is completed, the vacuum hood is used again to create a direct cooling environment. The cooling medium is input and directly acts on the vulcanization mold. There is no need to transfer the vulcanization mold. The temperature is quickly reduced to the softening temperature of 80℃-120℃ to achieve continuous production status.

[0017] The temperature measuring port of the vulcanization mold is located on the mold surface of the vulcanization mold, which can reflect the temperature of the vulcanization mold as accurately as possible, thereby achieving precise temperature control. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The figure is a schematic diagram of the manufacturing process of the perfluoroether rubber part of the present invention.

[0019] Figure 2 It is a schematic diagram of the vulcanization mold and vacuum cover of the present invention. DETAILED DESCRIPTION

[0020] In order to make the above features and advantages of the present invention more obvious and easy to understand, embodiments are given below with reference to the accompanying drawings for detailed description as follows.

[0021] like Figure 1-Figure 2 As shown, this embodiment provides a method for manufacturing a perfluoroether rubber part, which specifically includes the following steps: S1. The perfluoroether raw rubber obtained by mixing and extrusion is placed in a vulcanization mold. The vulcanization mold includes an upper mold plate 11 and a lower mold plate 12. The upper mold plate 11 is installed on an upper heating platform 13, and the lower mold plate 12 is installed on a lower heating platform 14. The upper mold plate 11 and the lower mold plate 12 are both made of stainless steel with a thickness of no more than 30 mm to avoid heat accumulation in the vulcanization mold caused by an overly thick mold, which affects the cooling rate.

[0022] In addition, in order to improve the cooling efficiency of the vulcanization mold by the cooling medium, the upper mold plate 11 and the lower mold plate 12 are provided with a plurality of cooling holes 10, and the cooling holes 10 are provided for the cooling medium to pass through during the cooling stage. In order to reflect the temperature of the vulcanization mold as accurately as possible, in this embodiment, the temperature measuring port of the thermocouple of the temperature control system is arranged on the upper mold plate 11 and the lower mold plate 12, i.e., the mold joint surface of the vulcanization mold. Specifically, an installation groove is provided on the mold joint surface, and the temperature measuring port is arranged in the installation groove. The upper mold plate 11 and the lower mold plate 12 are provided with temperature measuring ports.

[0023] S2. A heating program is implanted in the temperature control system. After the perfluoroether raw rubber is placed in the vulcanization mold and the mold is closed, the heating is started. The temperature parameters of the vulcanization mold are monitored in real time through the temperature measuring port and fed back to the temperature control system. When the vulcanization mold is heated to 80℃-120℃ for the first insulation stage, the insulation time of the first insulation stage is more than 10 seconds (specifically set to 13 seconds) to allow the perfluoroether raw rubber to initially soften. The insulation temperature of 80℃-120℃ can be set according to the specific softening point of the perfluoroether raw rubber. Note that the temperature range near the softening point is not sufficient to cause the perfluoroether raw rubber to produce a vulcanization reaction.

[0024] S3. After the first heat preservation stage is over, the second heat preservation stage is continued. The temperature is still controlled in the temperature range near the softening point. At the same time, a vacuum cover 20 is set on the outside of the vulcanization mold. The vacuum cover 20 covers the lower template 12, the lower heating platform 14, the upper template 11 and the upper heating platform 13. In this way, a closed space is formed inside the vacuum cover 20 and outside the vulcanization mold. Operations such as pumping and filling and inputting cooling medium can be performed in the closed space. In the second heat preservation stage, the closed space is first evacuated to a vacuum degree of 1Pa-10kPa (specifically set to 6.5kPa). After the vacuum degree reaches the standard, the vulcanizer is controlled to perform the upper and lower pressing action and the upper and lower pressing times are set to 2-5 times (specifically set to 3 times), and the pressing pressure is 50kgf / cm 2 -150kgf / cm 2 (Specific setting is 100kgf / cm 2 ), the operation time of step S3 is 8.5 seconds. Before formal production, a small sample test is conducted to obtain the number of upper and lower pressing times and pressing pressure required for the fullness of the product for this perfluoroether raw rubber. The vulcanization mold is pressed up and down repeatedly while vacuuming to promote the softened perfluoroether raw rubber to flow and exhaust, fill the mold cavity and overflow. If the rubber overflows, it can meet the international standard ISO-3601-3 O-ring quality acceptance standard Table-1 CS highest level appearance specification.

[0025] S4. When the last upper and lower pressing action is completed and the perfluoroether raw rubber material overflows, open the vacuum cover 20, continue to heat up, heat the vulcanization mold to the vulcanization temperature and keep the temperature and pressure, the vulcanization pressure is 15MPa-20MPa (specifically set to 18MPa), the vulcanization time is 5min-15min (specifically set to 10min), and the perfluoroether raw rubber material is vulcanized once.

[0026] S5. The vacuum cover 20 is lowered to cover the vulcanization mold again, and a cooling medium is input into the vacuum cover 20 so that the cooling medium acts on the vulcanization mold. The cooling medium is liquid nitrogen, and the gas supply pressure is 1MPa-1.5MPa (specifically set to 1MPa), and the gas supply flow rate is 5L / min-8L / min (specifically set to 5L / min). The vulcanization mold is quickly cooled down, and the cooling time is 60 seconds. Note that in some other examples, the cooling medium can also be replaced with dry ice.

[0027] S6. During the cooling air injection process, when the temperature reaches the set temperature of 80°C-120°C (80°C-120°C can be set according to the specific softening point of the perfluoroether raw rubber), the cooling air injection is automatically stopped and the vacuum cover 20 rises and opens, then the mold is opened to take out the material and put in the next perfluoroether raw rubber, and the above actions are repeated to achieve continuous production.

[0028] When the vulcanization mold is opened and the material is taken out in step S6, the vulcanization mold is kept on the vulcanizer heating platform to ensure that the temperature of the vulcanization mold is kept at the set temperature. In the traditional vulcanization operation, the vulcanization mold is pushed to the loading station via the guide rail, and the material is loaded and unloaded by personnel or mechanical arms outside the heating platform. This situation causes the temperature of the vulcanization mold to cool down. The cooling situation is related to the indoor environment and the operation time of the loading and unloading personnel. It cannot be stably controlled and is easy to cause fluctuations in the softening process of the next batch of perfluoroether raw rubber in step S2.

[0029] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention shall be defined by the attached claims and their equivalents.

Claims

1. A method for manufacturing a perfluoroether rubber part, characterized in that: The specific steps include: S1. The perfluoroether raw rubber obtained by mixing and extrusion is placed in a vulcanization mold, and the temperature measuring port of the vulcanization mold is located on the mold surface of the vulcanization mold; S2, heat the vulcanization mold to 80℃-120℃ and keep it warm for more than 10 seconds to make the perfluoroether raw rubber material initially soften; S3, continue to keep warm, set a vacuum cover on the outside of the vulcanization mold, and press the vulcanization mold up and down repeatedly while evacuating the vacuum, so as to promote the softened perfluoroether raw rubber to flow and exhaust, fill the mold cavity and overflow; S4, heating the vulcanization mold to the vulcanization temperature and keeping the temperature and pressure; S5. Cover the vulcanization mold with a vacuum cover, input cooling medium into the vacuum cover, and quickly cool down the vulcanization mold; S6. When the temperature of the vulcanization mold drops to 80℃-120℃, stop the cooling medium, open the vacuum cover, and then open the mold to take out the material.

2. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The number of times of upper and lower pressing in step S3 is 2-5 times.

3. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The pressing pressure in step S3 is 50 kgf / cm 2 -150kgf / cm 2 .

4. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The vacuum degree in step S3 is 1Pa-10kPa.

5. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The vulcanization pressure in step S4 is 15MPa-20MPa.

6. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The cooling medium is liquid nitrogen or dry ice.

7. The method for manufacturing a perfluoroether rubber part according to claim 6, characterized in that: The cooling air supply pressure is 1MPa-1.5MPa, and the air supply flow rate is 5L / min-8L / min.

8. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The cooling time of step S5 is 45 seconds to 75 seconds.

9. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: The operation duration of step S3 is 5 seconds to 10 seconds.

10. The method for manufacturing a perfluoroether rubber part according to claim 1, characterized in that: When the mold is opened and the material is taken out in step S6, the vulcanizing mold is kept on the heating platform of the vulcanizing machine.

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