One-step pretreatment activating solution and pretreatment method before chemical copper plating of PET (Polyethylene Terephthalate) fiber

Abstract

The invention aims to provide a one-step pretreatment activating solution and a pretreatment method before chemical copper plating of PET (Polyethylene Terephthalate) fibers, and belongs to the technical field of chemical plating. An activation solution composed of dimethyl sulfoxide (DMSO), polyvinylpyrrolidone (PVP) and silver salt is innovatively provided, when the PET fiber is immersed in the activation solution, the DMSO enables the PET fiber to swell, a solvent can promote PVP molecules to enter a PET polymer chain, a surface physical interlocking network (SPIN) structure rich in PVP is formed on the surface of the PET fiber, the PET fiber is subsequently put into deionized water to be soaked, and the surface of the PET fiber is subjected to surface activation. The swelling structure collapses, so that the PVP is locked, and the sample is not substantially deformed or dissolved; the generated AgNPs are tightly attached to a PVP substrate, so that the adsorption performance of the PET fiber surface to silver nanoparticles is enhanced, and a large number of active sites are provided for subsequent copper deposition on the fiber surface. According to the method, one-step pretreatment is achieved, and the multi-step pretreatment process in traditional chemical plating is simplified.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical plating, and in particular relates to a one-step pretreatment activation solution and a pretreatment method before chemical copper plating of PET fibers. Background Art

[0002] Electroless plating is a technology that deposits metal on the surface of a substrate through chemical reactions. It can form a uniform metal coating on the surface of the substrate without applying an external current. Polyethylene terephthalate (PET) fiber is widely used due to its excellent mechanical properties and chemical stability. Electroless copper plating can give it high conductivity while retaining the flexibility and mechanical strength of the fiber. However, its surface chemical inertness and low polarity bring difficulties to subsequent metal plating.

[0003] Traditional methods usually use multi-step pretreatment (such as etching, sensitization and activation) to enhance metal adhesion, but the process is complicated and easily damages fiber properties. [1-3] At the same time, the use of conventional methods for pretreatment before chemical copper plating, and the use of etching solutions (such as chromic acid or concentrated sulfuric acid) can also pose a threat to the environment and operational safety.

[0004] [1]SQJiang, CWKan, CWMYuen, WKWong, Electroless nickel plating of polyester fiber, Journal of Applied Polymer Science, 108 (2008) 2630-2637.

[0005] [2]RHGuo,SQJiang,CWMYuen,MCFNg,An alternative process for electroless copper plating on polyester fabric,Journal of Materials Science:Materials in Electronics,20(2009)33-38.

[0006] [3] Summary of the invention

[0007] In view of the problems existing in the background technology, the purpose of the present invention is to provide a one-step pretreatment activation solution and a pretreatment method for PET fiber before chemical copper plating. The present invention innovatively proposes an activation solution composed of dimethyl sulfoxide (DMSO), polyvinyl pyrrolidone (PVP) and silver nitrate, so that the PET fiber is immersed in the activation solution to complete the pretreatment before chemical copper plating. The method realizes one-step pretreatment and simplifies the multi-step pretreatment process in traditional chemical plating.

[0008] To achieve the above object, the technical solution of the present invention is as follows:

[0009] A one-step pretreatment activation solution before chemical copper plating of PET fiber comprises DMSO, PVP and silver salt; wherein the mass ratio of DMSO, PVP and silver salt is 1:(0.01-0.03):(0.01-0.06).

[0010] Furthermore, the silver-containing compound is preferably silver acetate, silver nitrate, silver borofluoride (AgBF 4 )wait.

[0011] A one-step pretreatment method for PET fiber before chemical copper plating, comprising the following steps:

[0012] Step 1. Prepare the activation solution:

[0013] Mix PVP and DMSO, stir evenly, then add silver salt, continue stirring at room temperature to obtain an activation solution;

[0014] Step 2. Washing PET fibers:

[0015] The PET fiber is ultrasonically cleaned and then dried;

[0016] Step 3. Perform preprocessing:

[0017] The PET fiber obtained in step 2 is soaked in the activation solution obtained in step 1 for a period of time, and then the PET fiber is taken out and soaked in deionized water for a period of time. After soaking, the PET fiber is taken out and dried to obtain the pretreated PET fiber.

[0018] Furthermore, in step 3, the immersion time in the activation solution is 30-60 seconds; the drying temperature is 50-100° C., and the drying time is 1-2 hours.

[0019] The present invention also provides the chemical copper plating of the pretreated PET fiber, the specific process is:

[0020] The pretreated PET fiber is placed in a chemical copper plating solution to perform chemical copper deposition at room temperature; during the chemical plating process, air is introduced into the plating solution to improve the stability of the plating solution, and finally a PET fiber with a copper layer deposited on the surface is obtained.

[0021] Furthermore, the chemical copper plating solution contains sodium potassium tartrate (NaKC 4 H 4 O 6 ), copper sulfate (CuSO 4 ), sodium hydroxide (NaOH), nickel sulfate hexahydrate (NiSO 4 6H 2 O), disodium tetraacetate tetraethylenediamine (EDTA-2Na), potassium ferrocyanide (K 4 [Fe(CN) 6 ]), 2,2-bipyridine (C10H 8 N 2 ) and formaldehyde solution (CH 2 O).

[0022] The mechanism of the present invention is:

[0023] The present invention prepares an activation solution by spontaneously generating and uniformly dispersing AgNPs in DMSO. Silver nanoparticles (AgNPs) have a large specific surface area and excellent catalytic activity, and can effectively induce reduction deposition of copper ions in a chemical plating solution. Dimethyl sulfoxide (DMSO) is a highly polar organic solvent. When PET fibers are immersed in the activation solution, DMSO can make the PET fibers swell, and the solvent promotes polyvinyl pyrrolidone (PVP) molecules to enter the PET polymer chain, forming a surface physical interlocking network (SPIN) structure rich in polyvinyl pyrrolidone (PVP) on the surface of the PET fibers. When immersed in deionized water, this swelling structure collapses, thereby locking the PVP without causing substantial deformation or dissolution of the sample; the generated AgNPs are tightly attached to the PVP matrix, enhancing the adsorption performance of the PET fiber surface to the silver nanoparticles, and providing a large number of active sites on the fiber surface for subsequent copper deposition.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. The one-step pretreatment method of the present invention simplifies the complex process of multi-step pretreatment (etching, sensitization, activation, etc.) in traditional chemical plating, which not only reduces potential safety hazards during the treatment process, but also significantly improves operating efficiency.

[0026] 2. The DMSO of the present invention is a relatively environmentally friendly solvent, which replaces highly corrosive chemicals such as chromic acid or concentrated sulfuric acid commonly used in traditional processes, thereby reducing environmental pollution and the generation of chemical wastes.

[0027] 3. The present invention uses AgNPs with lower cost to replace palladium-based catalysts, which reduces the consumption of rare metals and contributes to the sustainable utilization of resources.

[0028] 4. The present invention enhances the surface adsorption capacity of PET fibers by DMSO and the active site-rich network structure formed by AgNPs, thereby significantly improving the uniformity of the copper plating layer and the bonding force with the fibers. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the metallographic diagram of PET fiber.

[0030] Figure 2 This is the metallographic image of PET fiber after activation.

[0031] Figure 3 Metallographic image of copper deposited on PET fiber. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the implementation modes and the accompanying drawings.

[0033] A one-step pretreatment activation solution before chemical copper plating of PET fiber comprises DMSO, PVP and silver salt. In the activation solution, DMSO is used as a solvent and a reducing agent, PVP is used as a dispersant and a protective agent, and the silver salt is used as a metal precursor of AgNPs. During the preparation of the activation solution, DMSO is oxidized to dimethyl sulfone, and the silver salt is reduced to AgNPs, that is, AgNPs can be spontaneously generated and dispersed in DMSO.

[0034] By immersing the PET fiber membrane in this activation solution, a PVP-rich SPIN structure was formed on the surface of the PET fiber; AgNPs were tightly adsorbed on the PVP, generating a large number of active sites on the fiber surface; subsequently, copper was deposited on the PET fiber through ELP to form a conductive fiber.

[0035] Example 1

[0036] A method for chemical copper plating based on a one-step pretreatment activation solution comprises the following steps:

[0037] Step 1: Prepare activation solution, specific process:

[0038] 0.3 g PVP (MW 40000, K30) and 10 g DMSO were placed in a sealed bottle, stirred at room temperature for 1 h, and then 0.1 g silver nitrate was added, and then the solution was stirred at 35°C for 30 min to obtain an activation solution;

[0039] Step 2: PET fiber surface pretreatment, specific process:

[0040] The PET fiber is placed in a beaker containing anhydrous alcohol and rinsed with an ultrasonic cleaner at room temperature; the PET washed with alcohol is then rinsed with deionized water to remove the residual alcohol on the PET fiber, and then the substrate is placed in an oven and dried to obtain clean PET fiber;

[0041] Step 3: Activation of PET fiber, specific process:

[0042] The PET fiber obtained in step 2 is immersed in the activation solution obtained in step 1 for 30 minutes, and then immersed in deionized water for 30 seconds; the activated PET fiber is dried in an oven at 50° C. for 1 hour to remove excess solvent;

[0043] Step 4: Chemical copper plating, specific process:

[0044] The PET fiber activated in step 3 is immersed in a 35° C. plating bath for chemical copper deposition. During the chemical plating process, air is introduced into the plating solution to improve the stability of the plating solution, and finally a PET fiber with a copper layer deposited on the surface is obtained;

[0045] Among them, the copper plating solution contains sodium potassium tartrate (NaKC 4 H 4 O 6 , 32.0g / L), copper sulfate (CuSO 4 , 12.5g / L), sodium hydroxide (NaOH, 10.0g / L), nickel sulfate hexahydrate (NiSO 4 6H 2 O, 3.5 g / L), disodium tetraacetate tetraethylenediamine (EDTA-2Na, 2.5 g / L), potassium ferrocyanide (K 4 [Fe(CN) 6 ], 10.0 mg / L), 2,2-bipyridine (C10H 8 N 2 , 10.0 mg / L) and formaldehyde solution (CH 2 O, 12.0ml / L).

[0046] Example 2

[0047] A method for chemical copper plating based on a one-step pretreatment activation solution comprises the following steps:

[0048] Step 1: Prepare activation solution, specific process:

[0049] 0.1 g PVP (MW 40000, K30) and 10 g DMSO were placed in a sealed bottle, stirred at room temperature for 1 h, and then 0.6 g silver nitrate was added, and then the solution was stirred at 35°C for 30 min to obtain an activation solution;

[0050] Step 2: PET fiber surface pretreatment, specific process:

[0051] The PET fiber is placed in a beaker containing anhydrous alcohol and rinsed with an ultrasonic cleaner at room temperature; the PET washed with alcohol is then rinsed with deionized water to remove the residual alcohol on the PET fiber, and then the substrate is placed in an oven and dried to obtain clean PET fiber;

[0052] Step 3: Activation of PET fiber, specific process:

[0053] The PET fiber obtained in step 2 is immersed in the activation solution obtained in step 1 for 30 minutes, and then immersed in deionized water for 60 seconds; the activated PET fiber is dried in an oven at 80° C. for 1 hour to remove excess solvent;

[0054] Step 4: Chemical copper plating, specific process:

[0055] The PET fiber activated in step 3 is immersed in a 35° C. plating bath for chemical copper deposition. During the chemical plating process, air is introduced into the plating solution to improve the stability of the plating solution, and finally a PET fiber with a copper layer deposited on the surface is obtained;

[0056] Among them, the copper plating solution contains sodium potassium tartrate (NaKC 4 H 4 O 6 , 32.0g / L), copper sulfate (CuSO 4 , 12.5g / L), sodium hydroxide (NaOH, 10.0g / L), nickel sulfate hexahydrate (NiSO 4 6H 2 O, 3.5 g / L), disodium tetraacetate tetraethylenediamine (EDTA-2Na, 2.5 g / L), potassium ferrocyanide (K 4 [Fe(CN) 6 ], 10.0 mg / L), 2,2-bipyridine (C10H 8 N 2 , 10.0 mg / L) and formaldehyde solution (CH 2 O, 12.0ml / L).

[0057] Comparative Example 1

[0058] 0.3 g PVP (MW 40000, K30) and 10 g deionized water were placed in a sealed bottle, stirred at room temperature for 1 h, and then 0.1 g silver nitrate was added, and then the solution was stirred at 35° C. for 30 min to obtain an activation solution; the other steps were the same.

[0059] The color of the activation solution did not change during the comparative experiment, which indirectly indicates that the silver ions were not reduced to silver particles. At the same time, the PET fiber after chemical copper plating had no obvious metallic copper color and was black, and the bonding force was poor.

[0060] Figure 1 This is the metallographic diagram of PET fiber. Figure 2 is the metallographic image of PET fiber after activation, and Figure 1 By comparison, it can be found that the color of the activated PET fiber has changed to the color of the activation liquid, indicating that the activation treatment has been successfully carried out and the dispersion is uniform. Figure 3 This is the metallographic image of PET fiber after chemical copper plating. From the image, we can see that the PET fiber has been metallized and has obvious copper metal color on the surface.

[0061] The above description is only a specific implementation mode of the present invention. Any feature disclosed in this specification, unless otherwise stated, can be replaced by other alternative features that are equivalent or have similar purposes; all the disclosed features, or all the steps in the methods or processes, except for mutually exclusive features and / or steps, can be combined in any way.

Claims

1. A one-step pretreatment activation solution for PET fiber before chemical copper plating, characterized in that: It includes DMSO, PVP and silver salt; wherein the mass ratio of DMSO, PVP and silver salt is 1:(0.01-0.03):(0.01-0.06).

2. The one-step pretreatment activation solution according to claim 1, characterized in that: The silver salt is silver acetate, silver nitrate or silver borofluoride (AgBF4).

3. A one-step pretreatment method for PET fiber before chemical copper plating, characterized in that: The following steps are involved: Step 1. Prepare the activation solution: Mix PVP and DMSO, stir evenly, then add silver salt, continue stirring at room temperature to obtain an activation solution; Step 2. Washing PET fibers: The PET fiber is ultrasonically cleaned and then dried; Step 3. Perform preprocessing: The PET fiber obtained in step 2 is soaked in the activation solution obtained in step 1 for a period of time, and then the PET fiber is taken out and soaked in deionized water for a period of time. After soaking, the PET fiber is taken out and dried to obtain the pretreated PET fiber.

4. The one-step pretreatment method according to claim 3, characterized in that: In step 3, the immersion time in the activation solution is 30-60 seconds; the drying temperature is 50-100° C., and the drying time is 1-2 hours.

5. A method for chemical copper plating based on pretreated PET fiber, characterized in that: The specific process of chemical copper plating: The PET fiber pretreated by the one-step pretreatment method according to any one of claims 3 or 4 is placed in a chemical copper plating solution to perform chemical copper deposition at room temperature; during the chemical plating process, air is introduced into the plating solution to improve the stability of the plating solution, and finally a PET fiber with a copper layer deposited on the surface is obtained.

6. The PET fiber according to claim 5 is subjected to chemical copper plating, characterized in that: The chemical copper plating solution contains potassium sodium tartrate, copper sulfate, sodium hydroxide, nickel sulfate hexahydrate, disodium tetraacetate tetraethylenediamine, potassium ferrocyanide, 2,2-bipyridine and formaldehyde solution.

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