The four major factors that affect the performance of conductive adhesives mainly include:

1. Types, shapes and sizes of conductive particles:

1. Types: Conductive particles are the main component of conductive adhesives, determining the conductivity of the adhesive. Common conductive particles include metal particles, carbon black particles, and conductive ceramic particles, among others. Among them, metal particles have the best conductivity, but they are more expensive, so most conductive adhesives use carbon black particles. 

2. Shape and Size: The electrical conductivity of conductive adhesive is also influenced by the shape and size of the conductive particles. Irregularly shaped or overly small conductive particles may affect the adhesion and cohesion, thereby reducing the electrical conductivity.

II. Types and Contents of Adhesives:

1. Type: Adhesive is a "binding agent" between conductive particles, which enables the conductive particles to form a certain degree of combination and ensures the adhesion and stability of the conductive adhesive. Common adhesives include organic polymer materials, such as acrylates, epoxy resins, and polyurethanes, etc.

2. Content: The amount of adhesive and the quality of the adhesive directly affect the electrical conductivity of the conductive adhesive. Excessive adhesive will hinder the electron conduction between conductive particles, resulting in a decline in conductivity; while insufficient adhesive will affect the adhesion force between conductive particles, reducing the stability of the conductive adhesive.

III. Temperature and Pressure Conditions:

1. Temperature: Temperature directly affects the hardening degree of conductive adhesive, thereby influencing its electrical conductivity. Generally speaking, the adhesion strength and electrical conductivity of conductive adhesive both increase with the rise in temperature. However, when the temperature is too high, it may cause problems such as scorching and oxidation of the conductive adhesive.

2. Pressure: During the manufacturing process, appropriate pressure processing can enhance the stability and hardening degree of the conductive adhesive, thereby improving its conductive performance.

IV. Humidity and Moisture Content:

Humidity: Excessive humidity can cause the adhesion strength of conductive glue to decrease and make it prone to deformation, resulting in a decline in conductive performance.

2. Moisture Content: Excessive moisture content can cause problems such as crystallization and insufficient hardening of the conductive adhesive, thereby affecting its conductivity. The plasticizing effect of water can reduce the glass transition temperature of the polymer and the modulus of the adhesive, while the swelling effect of water can generate swelling stress and even lead to irreversible physical and chemical changes.

In summary, the performance of conductive adhesives is influenced by various factors such as conductive particles, adhesives, temperature and pressure conditions, as well as humidity and moisture content. When manufacturing and applying conductive adhesives, it is necessary to comprehensively consider these factors to achieve the best conductive performance and stability.