CN-117601386-B - Extruder, conductive foam and preparation method thereof

CN117601386BCN 117601386 BCN117601386 BCN 117601386BCN-117601386-B

Abstract

An extruder, conductive foam and a preparation method thereof belong to the technical field of conductive foam. The method comprises the steps of conveying metal sheets to a first feeding channel of an extruder, conveying a mixture of conductive silica gel raw materials to a second feeding channel, simultaneously conveying the metal sheets in the first feeding channel and the mixture in the second feeding channel to an extrusion port by utilizing a conveying component, extruding the mixture through the extrusion port to enable the mixture to be attached to the metal sheets to obtain double-layer extrusion materials, vulcanizing the double-layer extrusion materials, and bonding the mixture to the metal sheets to obtain the conductive foam. The conductive foam provided by the example of the application has the advantages that the metal layer is not easy to crack and fall off, the welding strength is high, and the structure is good in stability.

Inventors

ZHANG YAN
DOU LANYUE
ZHAO YUANYUAN
ZHAO HUIWEN

Assignees

深圳市鸿富诚新材料股份有限公司

Dates

Publication Date: 20260512
Application Date: 20231229

Claims (11)

1. An extruder, which comprises a die-casting die, characterized by comprising the following steps: The extruder body is internally provided with a first feeding channel, a second feeding channel and an extrusion port, wherein the discharge end of the first feeding channel and the discharge end of the second feeding channel are converged at the extrusion port, so that a sheet material conveyed by the first feeding channel and a sizing material conveyed by the second feeding channel are adhered at the feeding position of the extrusion port and enter the extrusion port; The conveying assembly comprises a pushing piece and a pushing screw, wherein the pushing piece is arranged in the first feeding channel and is used for conveying sheet materials in the first feeding channel to the extrusion port, the pushing screw is arranged in the second feeding channel and is used for pushing sizing materials in the second feeding channel to the extrusion port, the first feeding channel is flat, the second feeding channel is positioned on one side of the first feeding channel in the narrower direction and enables the sizing materials to be directly transferred to the surface of the sheet materials, the second feeding channel is positioned above the first feeding channel, and the bottom wall of the second feeding channel and the top wall of the first feeding channel are co-walled at the extrusion port.
2. The extruder of claim 1 wherein said pusher comprises a plurality of rollers rotatably disposed within said first feed channel at spaced intervals along the direction of extension of said first feed channel, the axial direction of said rollers extending in the direction of the wider of said first feed channel in the shape of a flat.
3. The extruder of claim 2 wherein said conveying assembly further comprises two guides disposed at both ends of said first feed channel in said widthwise direction for guiding both sides of said sheet material conveyed by said rollers.
4. The preparation method of the conductive foam is characterized by comprising the following steps: Conveying a metal sheet to the first feed channel and a mixture of conductive silica gel raw materials to the second feed channel using the extruder of any one of claims 1 to 3; simultaneously conveying the metal sheet in the first feeding channel and the mixture in the second feeding channel to the extrusion port by using the conveying assembly, and extruding the mixture through the extrusion port to bond the mixture to the metal sheet to obtain a double-layer extrusion material; And vulcanizing the double-layer extrusion material to obtain the conductive foam.
5. The method for preparing conductive foam according to claim 4, wherein the conductive silica gel raw material comprises 100 to 120 parts by weight of vinyl silicone gel, 50 to 70 parts by weight of conductive filler and 2 to 5 parts by weight of vulcanizing agent.
6. The method for preparing conductive foam according to claim 5, wherein the conductive filler is one or more selected from the group consisting of silver-plated conductive powder, nickel powder and conductive fiber; the metal sheet is made of one of copper and its alloy, and iron and its alloy.
7. The method of manufacturing a conductive foam according to claim 6, wherein the metal sheet is made of stainless steel or phosphor bronze.
8. The method of producing conductive foam according to claim 6, wherein the thickness of the metal sheet is 0.05-0.15 mm.
9. The method for preparing conductive foam according to claim 4, wherein a metal coating is provided on a side of the metal sheet facing away from the mixture.
10. The method for preparing conductive foam according to claim 9, wherein the metal plating layer is made of one or more selected from gold, tin and nickel.
11. A conductive foam produced according to the production method of any one of claims 4 to 10.

Description

Extruder, conductive foam and preparation method thereof Technical Field The application relates to the technical field of conductive foam, in particular to an extruder, conductive foam and a preparation method thereof. Background Conductive foam capable of being attached by SMT technology (hereinafter referred to as SMT conductive foam) is generally made by wrapping an elastomer with a polymer film with a metal conductive layer such as copper, tin, gold and the like on the surface by a wrapping process, wherein the elastomer generally adopts silica gel with good rebound resilience. In the development and production of the current SMT conductive foam product, the production mode is complex, and the production mode comprises the steps of extrusion, vulcanization, cooling of an elastomer, bonding of the elastomer and a conductive layer through a die and the like, and certain inherent problems exist in the production process, such as 1, in the bonding and wrapping process of the elastomer and the conductive layer, an adhesive overflows to the surface of the conductive layer to reduce the electrical property of the conductive layer, 2, when a finished product is wrapped or cut, the surface of the conductive layer is uneven in appearance, and 3, the conductive layer is broken during the forming processing. In addition, the traditional SMT conductive foam is easily lifted by external force under long-term and repeated compression load after being welded on a PCB in the actual use process, so that the traditional SMT conductive foam is separated from the PCB and loses conduction performance. In addition, when repeated and concentrated pressure is applied, the metal layer on the surface of the SMT conductive foam can be broken or fall off, so that the efficiency is affected. These problems have presented a great challenge to the production and use of SMT conductive foam, and multiple processes have also made it difficult to increase its yield, which in turn presents a problem for large-scale production. Disclosure of Invention Based on the defects, the application provides an extruder, conductive foam and a preparation method thereof, so as to partially or completely improve the problems of poor stability and preparation of the conductive foam in the related art. The application is realized in the following way: In a first aspect, examples of the present application provide an extruder comprising an extruder body and a conveying assembly. The feeding device comprises an extruder body, a feeding assembly and a pushing screw, wherein a first feeding channel, a second feeding channel and an extrusion port are arranged in the extruder body, the discharging end of the first feeding channel and the discharging end of the second feeding channel are converged at the extrusion port, so that sheet materials conveyed by the first feeding channel and sizing materials conveyed by the second feeding channel are attached to each other at the feeding position of the extrusion port and enter the extrusion port, the feeding assembly comprises a pushing piece and the pushing screw, the pushing piece is arranged in the first feeding channel and used for conveying sheet materials in the first feeding channel to the extrusion port, and the pushing screw is arranged in the second feeding channel and used for pushing sizing materials in the second feeding channel to the extrusion port. In the implementation process, the extruder is provided with the first feeding channel and the second feeding channel which are converged at the position of the extrusion opening, the first feeding channel is internally provided with the pushing piece, the second feeding channel is internally provided with the pushing screw rod, the pushing piece can be used for conveying the sheet material from the first feeding channel to the extrusion opening, and meanwhile, the pushing screw rod is used for conveying the colloid material from the second feeding channel to the extrusion opening, so that the sheet material and the colloid material are contacted at the extrusion opening and jointly extruded through the extrusion opening, and a double-layer extrusion material with the sheet material and the colloid material being attached is obtained. The extruder provided by the example of the application is used for preparing the conductive foam, the metal sheet and the conductive sizing material can be extruded together, so that the mixture of the metal sheet and the conductive silica gel raw material is attached, and then the mixture is formed into the conductive silica gel with elasticity, which is self-adhered to the surface of the metal sheet after the subsequent vulcanization treatment, so that the conductive foam is obtained, the preparation process of the conductive foam can be simplified, and the stability of the conductive foam is improved. In combination with the first aspect, in an alternative embodiment of the application, the first feed channel is flat and t