Injection Molding: Chemical Additives

The purpose of using chemical addictive is to improve the function or to prevent deterioration.

Below we list out some kinds of chemical additives which can be used during production, the additives can be divided into two categories:


A. Function improvement


Name

Usage

Plasticizer Fluidity of molten plastic material can be improved by adding some plasticizer, the material will be much easier to be used for manufacturing, meanwhile, brittleness can be lower.
Filler

Main purpose of using filler including (1) reduce the cost (2) improve the quality of the finish product or the feature of material 

E.g.
By filling glass fiber, asbestos fiber, or carbon fiber, the strength of final product can be improved.
By filling sawdust, the cost can be reduced.
By filling mica or asbestos, the heat-resisting of final product can be better.

Please check out more information in: Injection Molding: Filler / Reinforcement

Colorant  To make the final product aesthetic and functional, we can mix the plastic material with toner or dyes, sometimes the colorant is used for particular purposes.
Lubricant

Lubricant is used to reduce friction between two surfaces, by adding adequate lubricant, the finish product can be easier released from the mold.

Curing agent

Also called hardener. By adding some curing agent, the hardness of plastic final product can be increased.

Fire retardant

Suitable to be used in architecture or furniture to reduce the damage of fire disaster.
Fire retardant is not combustion supporting, the use of is fire retardant is aim to reduce the possibility of burning, which means that it's not fireproof.

Blowing agent Once heated, the blowing agent causes chemical reaction and exhaust gas to form a hollow and porous interior, e.g. styrofoam
Antistatic agent

The use of antistatic agent can reduce the buildup of static electricity and prevent the adherence of dust, therefore, the working efficiency can be improved.

Totally Degradable Plastics Additives (TDPA) The plastic product can be degradable by the use TDPA to achieve the target of environment conservation.




B. To prevent deterioration

In order to prevent the deterioration of plastic final products, we can mix the plastic material with some stabilizer.


Name

Usage

Heat stabilizer Heat stabilizer can stop the plastic form degrading if heated.
Antioxidant

A kind of oxygen-proof material which used in production of plastic product, the purpose is to prevent the occurrence of oxidation from exposure to sunlight or radiation.

Antiozonant Antiozonant can react with Ozone instead of polymer, thus we can mix the plastic material with adequate antiozonant to stop the aging crack from happening.
UV-stabilizer

UV-stabilizer is suitable to be used for outdoor products which need to resist long-term exposure to sunlight, we can prevent the damage of ultraviolet ray by using some of the stabilizer during production.