A degradable copper-clad plate preparation technology

Abstract

This invention discloses a biodegradable copper-clad laminate (CCL) preparation technology, belonging to the field of electronic materials technology. The CCL uses agricultural waste corn stalks and starch as a matrix, compounded with gum arabic, vanillin, and a silane coupling agent. Through in-situ construction of a dynamic imine bond and a dynamic siloxane bond dual-dynamic cross-linking structure, it achieves efficient biodegradation under mild conditions while ensuring the substrate's mechanical strength, toughness, and water resistance. The raw materials are in the following weight proportions: corn stalks 45-68 parts, starch 30-45 parts, gum arabic 15-30 parts, vanillin 5-13 parts, and silane coupling agent 20-30 parts. The preparation method involves mixing and stirring the raw materials into a viscous system, placing it in a mold, and laying copper foil on both sides, followed by hot pressing at 140℃. This invention uses readily available raw materials, has a simple process, and is low in cost. It achieves an 86% biodegradability rate after 45 days of burial, making it suitable for green biodegradable electronic devices and solving the problems of difficult degradation and low utilization rate of agricultural waste in traditional petroleum-based CCLs.

Description

Technical Field

[0001] This invention relates to the field of electronic materials technology, specifically to a biodegradable copper-clad laminate preparation technology. Background Technology

[0002] With the rapid development of the electronics industry, copper-clad laminates (CCLs) are widely used as a core substrate for printed circuit boards (PCBs). Traditional CCLs are mostly made from petroleum-based materials such as epoxy resin and glass fiber, which are difficult to degrade and easily cause environmental pollution after disposal. Meanwhile, my country has a large corn planting area, generating a large amount of agricultural waste such as corn cobs and corn stalks every year, with low utilization rates and serious resource waste. Existing biodegradable CCLs mostly rely on chemically modified resins, which have problems such as high cost, complex processes, and demanding equipment requirements. Therefore, developing a biodegradable plant-based CCL that uses readily available raw materials, has a simple process, low cost, and is biodegradable is of great significance. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a plant-based biodegradable copper clad laminate that uses agricultural waste as raw material, has a simple process, low cost, and is biodegradable, as well as a method for its preparation.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a plant-based biodegradable copper-clad laminate containing dynamic imine bonds and dynamic silicon-oxygen bonds, using corn stalks and starch as the matrix, introducing dynamic imine bonds as the main degradation sites, and combining them with dynamic silicon-oxygen bonds to improve structural stability and water resistance, achieving multiple degradation pathways while ensuring the strength and toughness of the substrate. The copper-clad laminate is made from the following raw materials in parts by weight:

[0005] Corn stalks: 45–68 parts

[0006] Starch: 30-45 parts

[0007] Peach gum: 15-30 parts

[0008] Vanillin: 5-13 parts

[0009] Silane coupling agent: 20-30 parts

[0010] Lemon juice: 3-5 parts

[0011] Preferably, the starch is corn starch. Corn starch is widely available, has strong adhesive properties after gelatinization, rapid biodegradation, and good compatibility with plant fibers. It can effectively bind corn stalk fibers together, improving the formability and mechanical stability of the substrate, while further enhancing the overall biodegradability of the material.

[0012] Preferably, the vanillin molecule contains an aldehyde group (-CHO) and a benzene ring structure. The aldehyde group can react with active groups such as hydroxyl and amino groups to form a dynamic imine bond (-CH=N-) in situ. This dynamic imine bond can be reversibly broken and reconstructed under mild conditions, giving the material controllable degradation and recyclability. The benzene ring structure has a certain rigidity, which can improve the mechanical strength and heat resistance of the substrate. In addition, vanillin is derived from natural biomass, is green and non-toxic, environmentally friendly, and has excellent compatibility with the plant-based system of this invention.

[0013] Preferably, the silane coupling agent is KH-550. The silane coupling agent molecule contains both alkoxysilane groups and amino groups. One end can form a stable bond with the hydroxyl and carboxyl groups in the plant-based raw material, while the other end can introduce dynamic siloxane bonds (Si-O-Si), forming a flexible cross-linked network in the matrix. These dynamic siloxane bonds can improve the material's water resistance, toughness, and structural stability, and inhibit premature hydrolysis of dynamic imine bonds. Furthermore, the inherent hydrophobicity of dynamic siloxane bonds can reduce the matrix's water absorption rate and inhibit imine bond hydrolysis, achieving a balance between degradability and practicality.

[0014] Preferably, the main component of the peach gum is a natural polysaccharide polymer with a large number of hydroxyl groups (-OH) on its molecular chain. On the one hand, it can form strong hydrogen bonds with plant-based raw materials such as corn stalk fiber and starch, improving the adhesion between raw materials and the formability of the substrate, ensuring that the substrate has sufficient mechanical strength and toughness, and is not easy to crack or break. On the other hand, peach gum has good reactivity and film-forming properties, and can react with vanillin to generate dynamic imine bonds in situ. At the same time, it forms a gel with KH-550 silane coupling agent, effectively incorporating dynamic imine bonds and dynamic siloxane bonds into the plant matrix, achieving the synergistic effect of dual dynamic bonds. In addition, peach gum is derived from natural plants, is non-toxic, completely biodegradable, and environmentally friendly. It is highly compatible with the overall plant-based system of this invention, does not introduce non-degradable components, and ensures that the copper-clad laminate can be completely degraded in the natural environment.

[0015] In summary, this invention constructs dynamic imine bonds (-CH=N-) through an in-situ condensation reaction between vanillin and the hydroxyl groups on the gum arabic molecular chain, endowing the matrix with controllable degradation properties. Then, natural plant-based components such as corn starch and corn stalk fiber are introduced as the matrix framework, and dynamic silicon-oxygen bonds (Si-O-Si) are formed in the system using a silane coupling agent. Through the synergistic crosslinking of dynamic imine bonds and dynamic silicon-oxygen bonds, the plant-based matrix achieves efficient degradation under mild conditions while maintaining good mechanical strength, toughness, and water resistance, ultimately yielding a fully plant-based, dual-dynamic-bond synergistic degradable copper-clad laminate.

[0016] In this invention, the silane coupling agent constructs dynamic silicon-oxygen bonds (Si-O-Si) in the system. These bonds possess excellent hydrophobicity and structural stability, forming a hydrophobic protective layer on the surface of the plant substrate. This effectively inhibits water molecule penetration and prevents premature hydrolysis failure of the dynamic imine bonds under humid and hot conditions, significantly improving the substrate's water resistance, dimensional stability, and mechanical strength. Simultaneously, the dynamic silicon-oxygen bonds can undergo reversible breakage and reconstruction under specific conditions, forming a dual dynamic bond synergistic system with the dynamic imine bonds. This allows the material to maintain both good performance stability and high-efficiency biodegradability. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to specific embodiments.

[0018] Preparation Example 1

[0019] A biodegradable copper-clad laminate is prepared by the following method:

[0020] Step S1: Mix corn stalk powder and corn starch according to the weight parts, stir evenly and keep dry.

[0021] Step S2: Add the peach gum aqueous solution and stir until the system becomes a paste.

[0022] Step S3: Mix the peach gum aqueous solution with the silane coupling agent KH-550, let it stand, and then add the gel-like substance to the above-mentioned batter system. Continue stirring until it becomes viscous.

[0023] Step S4: Mix vanillin and lemon juice until liquid, then add to the above batter system and continue stirring until thickened.

[0024] Step S5: Place the obtained semi-finished product into a 10cm×10cm×1.6mm mold, place a copper foil on the top and bottom, flatten it, and then heat press it at 140℃ for about 12 minutes. Remove it and cool it to obtain a plant-based biodegradable copper-clad laminate. Performance testing

[0025] Degradability: According to the formula To calculate the biodegradability, where m0 is the initial amount and m1 is the remaining amount, the biodegradability after 45 days is 86%.

[0026] Water absorption: According to the formula in GB / T 4722-2017 The test showed a water absorption rate of 30%.

[0027] The results compared with traditional FR-4 fiberglass boards and aluminum substrates are as follows:

[0028] Reference Degradability Water absorption rate FR-4 fiberglass board 0.5% 0.3% Aluminum substrate 8.2% 0.05% Copper-clad laminate of the present invention 86% 30%

[0029] This invention uses agricultural waste as raw material, which is low-cost, simple to process, and biodegradable, making it more in line with the development needs of green electronic materials.

Claims

1. A biodegradable copper-clad laminate preparation technology, characterized in that, Made from the following parts by weight of raw materials: Corn stalks 45–68 parts; starch 30–45 parts; peach gum 15–30 parts; vanillin 5–13 parts; silane coupling agent 20–30 parts; lemon juice 3–5 parts.

2. The copper-clad laminate according to claim 1, characterized in that, The starch is corn starch.

3. The copper-clad laminate according to claim 1, characterized in that, The silane coupling agent is KH-550.

4. The copper-clad laminate according to claim 1, characterized in that, The copper-clad laminate contains a dual dynamic cross-linking structure of dynamic imine bonds (-CH=N-) and dynamic silicon-oxygen bonds (Si--Si).

5. A method for preparing the plant-based biodegradable copper-clad laminate according to any one of claims 1-4, characterized in that, Includes the following steps:

1. Dry and mix corn stalk powder and starch evenly; 2. Add peach gum aqueous solution and stir until it becomes a paste; 3. Mix peach gum aqueous solution with silane coupling agent to obtain a gel, add it to the above paste system and stir until it becomes viscous; 4. Mix vanillin and lemon juice and stir until it becomes liquid, then add it to the above paste system and continue stirring until it becomes viscous.

5. Place the semi-finished product in the mold, place copper foil on the top and bottom, and hot press at 140°C to form the copper-clad laminate.

6. The preparation method according to claim 5, characterized in that, The total hot pressing time is 11 to 13 minutes.