Application of Antistatic Agents in Plastic Product Production

Antistatic agents are key functional additives in plastic production. They form conductive films by adsorbing moisture from the air or directly conducting charges, eliminating the accumulation of static electricity caused by strong insulation and friction in plastics, and avoiding problems such as dust adsorption, electric shock, and fire caused by static electricity. In plastic production (such as injection molding, extrusion, blow molding) and subsequent use, the static voltage can reach tens of thousands of volts, which not only affects production efficiency (such as film adhesion, difficult product handling), but also may endanger the safety of flammable and explosive scenes (such as chemical packaging, electronic components). It is compatible with almost all plastics such as PE, PP, PVC, PET, ABS, etc., and can be divided into internal and external coating types according to usage. Currently, it is developing towards high efficiency, long-term effect, and low migration, becoming an important link in ensuring smooth plastic production and product safety.

1、 The core mechanism of action of anti-static agents: targeted solution to the problem of static electricity accumulation

Plastic static electricity originates from charge transfer caused by molecular friction, and antistatic agents achieve charge elimination through two core mechanisms, suitable for different production and usage scenarios:

1. External coating type: rapidly forming conductive thin film

External anti-static agents adhere to the surface of plastic products through spraying, soaking, and other methods, using their hydrophilic groups to adsorb moisture in the air, forming a continuous conductive film that quickly conducts accumulated static charges to the ground:

Function characteristics: fast onset (immediately effective after coating), low cost, flexible operation, no need to change the plastic production formula;

Limitations: Easy to fall off due to friction and cleaning, poor long-term effectiveness (usually maintained for 1-3 months), suitable for short-term use or temporary anti-static needs;

Representative products: cationic (such as quaternary ammonium salts), non-ionic (such as polyethylene glycol fatty acid esters);

Adaptation scenario: Post processing of plastic films and injection molded parts, such as PE shopping bags and PP toy surface anti-static.

2. Internal addition type: Long term dispersed conductive charge

Internal anti-static agents are blended with raw materials during plastic production, uniformly dispersed in the plastic matrix, and migrate to the surface to form a conductive layer or construct conductive channels inside, achieving long-term anti-static:

Function characteristics: Strong long-term durability (consistent with the product's service life), uniform anti-static effect, and no impact on the processing performance of the product;

Limitations: The addition amount is relatively high (usually 0.5% -3%), the cost is higher than that of the external coating type, and it needs to be matched with the plastic processing temperature;

Representative products: non-ionic (such as glycerol fatty acid esters, polyethers), ionic (such as sulfonate salts);

Adaptation scenario: The raw material blending process in plastic production, such as the production of electronic component casings and chemical packaging drums.

2、 Mainstream anti-static agent types and their suitability for plastic production: characteristics and scene matching

There are significant differences in heat resistance, compatibility, and long-term effectiveness among different anti-static agents. The selection should be based on the type of plastic, processing technology (such as temperature, molding method), and product use. The following are the four core categories:

1. Non ionic anti-static agent: universal low toxicity, suitable for multi category plastic production

Non ionic anti-static agents have good compatibility, low toxicity, and moderate heat resistance (processing temperature ≤ 200 ℃), making them the most widely used type in plastic production. Both internal and external coatings can:

Representative products: Polyethylene glycol (PEG), glycerol monostearate (GMS), polyether complexes;

Compatible plastics: PE, PP, PVC, ABS, PET;

Production scenarios: PE film extrusion, PP injection molding production, PVC pipe processing, can avoid product adhesion and improve production efficiency.

2. Cationic anti-static agent: efficient and fast, suitable for external coating or low-temperature processing

Cationic anti-static agents have high anti-static efficiency (surface resistance can be reduced to 10 ⁶ -10 ⁸ Ω), but poor heat resistance (processing temperature ≤ 160 ℃), and are mostly used as external coatings. Some can be added internally to low-temperature processed plastics:

Representative products: Dodecyltrimethylammonium chloride, quaternary ammonium salt complexes;

Compatible with plastics: PVC, PE, ABS;

Production scenario: PVC film external coating treatment, ABS toy surface anti-static spraying, fast effect and can quickly reduce surface resistance.

3. Anionic anti-static agent: Good temperature resistance, suitable for high-temperature processing of plastics

Anionic antistatic agents have excellent heat resistance (processing temperature ≤ 250 ℃), slightly poor compatibility, and need to be used in combination with compatibilizers. They are mostly internal additives:

Representative products: alkyl sulfates, phosphate salts;

Compatible plastics: PET, PC, PA (polyamide);

Production scenario: PET beverage bottle blow molding, PC electronic component shell injection molding, can withstand high temperature processing without decomposition.

4. Composite anti-static agent: multifunctional synergy, suitable for high-end production needs

Composite anti-static agents are composed of two or more types of compounds (such as non-ionic+ionic type, anti-static+antioxidant type), which have the characteristics of high efficiency, long-term effect, and temperature resistance:

Representative products: polyether+quaternary ammonium salt complex, GMS+antioxidant 1010 complex;

Compatible plastics: PP, PE, PET, ABS;

Production scenario: High end electronic packaging material production, chemical PE barrel processing, can simultaneously solve static electricity and aging problems.

3、 Application practice of anti-static agents in the production of key plastic products: scenario based formula and process

The production processes and usage scenarios of different plastic products vary greatly, and the selection of anti-static agents needs to be customized based on "plastic type processing temperature product use". The following are typical cases:

1. Production of polyolefin products (PE, PP): Balancing production efficiency and safety of use

PE and PP are the most commonly used categories in plastic production, which can easily generate static electricity and cause film adhesion and product adsorption of dust. Commonly used internal non-ionic anti-static agents are:

PE shopping bag extrusion production:

Formula: PE raw material+0.8% polyethylene glycol fatty acid ester+0.2% antioxidant 1076;

Process: Blend with raw materials in an extruder at a processing temperature of 150-180 ℃;

Effect: The surface resistance of the film is reduced to 10 ⁸ -10 ⁹ Ω without adhesion, and the production efficiency is increased by 20%. It does not adsorb dust during use.

PP electronic component tray injection molding production:

Formula: PP raw material+1.5% polyether antistatic agent+0.3% compatibilizer;

Process: Injection molding temperature 180-200 ℃, mold temperature 50-60 ℃;

Effect: The surface resistance of the tray is ≤ 10 ΩΩ, which avoids electrostatic damage to electronic components and has a long-term durability of more than 2 years.

2. Production of engineering plastic products (PET, PC): Balancing high temperature resistance and low migration

PET and PC processing temperatures are high (260-320 ℃), and some are used in high-end scenarios such as food and electronics. Therefore, it is necessary to choose temperature resistant and low migration anti-static agents:

Production of PET beverage bottle blow molding:

Formula: PET raw material+1.2% phosphate salt antistatic agent+0.2% hypophosphite 168;

Process: Drying temperature of 160 ℃, blow molding temperature of 270-280 ℃;

Effect: The surface resistance of the bottle body is reduced to 10 Ω, avoiding electrostatic adsorption of dust during filling. The migration amount of anti-static agent is less than 0.01mg/kg, which meets the food contact standard.

PC computer shell injection molding production:

Formula: PC raw material+2.0% polyether+quaternary ammonium salt compound antistatic agent;

Process: Injection molding temperature 280-300 ℃, holding time 15-20 seconds;

Effect: The surface resistance of the shell is ≤ 10 ΩΩ, there is no static electric shock, and it does not affect the transparency and mechanical properties of the product.

3. PVC product production: adapted to different molding processes

PVC processing techniques are diverse (extrusion, injection molding, rolling), and static electricity problems are particularly prominent in the production of films and pipes. Commonly used internal or external anti-static agents are:

PVC transparent film rolling production:

Formula: PVC resin+1.0% glycerol monostearate+2.0% epoxy soybean oil (plasticizing and anti-static synergistic);

Process: Rolling temperature 160-180 ℃, cooling temperature 40-50 ℃;

Effect: The surface resistance of the film is 10 ⁸ -10 ⁹ Ω, with no adhesion or fog, and a transmittance retention rate of over 90%.

PVC chemical pipeline extrusion production:

Formula: PVC resin+1.5% alkyl sulfonate antistatic agent+3.0% calcium zinc composite heat stabilizer;

Process: Extrusion temperature 150-170 ℃, traction speed 5-8m/min;

Effect: The resistance of the inner wall of the pipeline is ≤ 10 ΩΩ, avoiding safety hazards caused by static electricity when transporting flammable and explosive liquids.

4. Production of electronic packaging plastics: high requirements for anti-static protection

Electronic packaging plastics (such as PE anti-static bags and ABS trays) have extremely high requirements for electrostatic protection (surface resistance of 10 ⁶ -10 ⁸ Ω), and high-efficiency composite anti-static agents need to be selected:

Production of PE anti-static bag blown film:

Formula: PE raw material+2.0% polyether+quaternary ammonium salt compound antistatic agent+0.3% antioxidant 1010;

Process: blown film temperature of 160-180 ℃, blowing ratio of 2.5-3.0;

Effect: The surface resistance of the bag body is 10 ΩΩ, and the electrostatic half-life is less than 2 seconds, which can effectively protect the internal electronic components from electrostatic damage.

4、 Challenges and Development Trends of Antistatic Agents in Plastic Production

Although anti-static agents have solved the key static electricity problem in plastic production, they still face challenges in compatibility, long-term effectiveness, environmental compliance, and other aspects in current applications. In the future, they will develop towards the direction of "high efficiency, long-term effectiveness, and green":

1. Current challenge: Balancing performance and production requirements

Compatibility and appearance contradiction: Some anti-static agents (such as ionic type) have poor compatibility with plastics, which can easily precipitate and cause the surface of the product to become sticky and foggy, affecting the appearance;

Long term effectiveness and cost balance: External coating has low cost but requires secondary processing, while internal coating has long term effectiveness but high dosage, increasing production costs;

Environmental compliance pressure: Some cationic anti-static agents (such as certain quaternary ammonium salts) have high toxicity and do not meet the environmental standards for food and pharmaceutical packaging.

2. Development trend: Technological innovation drives upgrading

High molecular weight antistatic agent: Develop antistatic agents with a molecular weight greater than 1000 (such as polyetheramide copolymers), improve compatibility with plastics through molecular chain entanglement, reduce precipitation, and adapt to high-end food and electronic packaging production;

Reactive anti-static agent: grafting anti-static groups onto plastic molecular chains to fundamentally solve migration problems, with long-term effectiveness consistent with product lifespan. It has been piloted in PET and PP production;

Biobased anti-static agent: made from plant extracts (such as castor oil derivatives and starch based compounds), low toxicity, biodegradable, in line with the "dual carbon" policy, suitable for environmentally friendly plastic production;

Multi functional integrated anti-static agent: Developing a "anti-static+antioxidant+weather resistant" composite additive, simplifying plastic production formulas, reducing processing costs, and adapting to outdoor and high-end plastic product production.

5、 Summary: Antistatic agents - the "safety guardians" of plastic production and use

From the smooth extrusion of PE shopping bags, to the electrostatic protection of electronic component trays, and to the safe production of chemical pipelines, anti-static agents ensure the efficient and smooth production of plastics and the safe use of products by accurately eliminating electrostatic hazards. It is not only an "auxiliary additive" to solve production pain points, but also directly affects the applicability (such as electronic packaging, chemical containers) and safety (such as flammable and explosive scenarios) of plastic products. In the future, with breakthroughs in the research and development of high molecular weight, bio based, and multifunctional anti-static agents, it will further adapt to the high-end and green development needs of the plastic industry, providing support for the production of more high demand plastic products.