There are two commonly used anti-static methods. The first is to increase the lubricity of the product and prevent the generation of static electricity; The second method is to accelerate the leakage of static charges. Therefore, there are two antistatic methods: one is to brush and spray on the surface of the product, which is a disposable antistatic agent; The other is to add it to the interior of production materials, that is, long-acting antistatic agent, which can achieve the antistatic effect for a long time. Both methods can improve the conductivity of the material and correspond to two different mechanisms of action.

Action mechanism of disposable antistatic agent

By combining with water molecules in the air, the hydrophilic group of antistatic agent forms a single molecular conductive film on the plastic surface, which can reduce the surface resistance and accelerate the leakage of charges. The dielectric constant in the friction gap is higher than that in the air, weakening the electric field and reducing the charge generated by conduction.

Action mechanism of long-acting antistatic agent

When a sufficient amount of antistatic agent is added to the resin, a dense arrangement will be formed on the resin surface, and the hydrophilic group will form a conductive layer toward the air side. The surface concentration is higher than the inside. During processing, due to the role outside the boundary, the antistatic agent molecules on the resin surface will be damaged, and the antistatic performance will decline. At the same time, the antistatic agent inside the resin will continue to seep out to the surface and migrate to the surface, Supplement the conductive layer of the missing anti-static molecules and form a water adsorption layer, which enhances the conductivity.

Classification of antistatic agent

1. Surfactant antistatic agent: cationic antistatic agent, anionic antistatic agent, zwitterion antistatic agent, non-ionic antistatic agent;

2. Conductive filler antistatic agent: mainly including conductive carbon black, carbon fiber, metal and metal oxide, etc. If carbon black and carbon fiber are added to polymer materials, they can obtain materials with antistatic properties and sustained antistatic properties, without any problems of seepage or frost.

Polymer antistatic agent is the focus of international research at present, but it has not been widely used. The commercialized polymer antistatic agent abroad is not rare. Japan Asahi Kasei Industrial Co., Ltd. uses polyethylene glycol polyamide as permanent antistatic agent. Japanese Ink Company adopts polydiglycidyl ether glycol, and adds alkali metal or alkaline earth metal as long-term antistatic agent.