Plastic additives, also known as plastic additives, is a polymer (synthetic resin) for molding and processing in order to improve its processing performance or in order to improve the performance of the resin itself is insufficient and must be added to a number of compounds.

A large class of additives for plastic molding and processing products, including plasticizers, heat stabilizers, antioxidants, light stabilizers, flame retardants, foaming agents, antistatic agents, mildew agents, coloring agents and whitening agents (see pigments), fillers, coupling agents, lubricants, mold release agents and so on.

How to choose additives?
The specific selection range of additives is as follows:
Toughening - select elastomers, thermoplastic elastomers and rigid toughening materials;
Reinforcement - select glass fibers, carbon fibers, whiskers and organic fibers;
Flame retardant - bromine (ordinary bromine and environmentally friendly bromine), phosphorus, nitrogen, nitrogen/phosphorus composite intumescent flame retardants, antimony trioxide, hydrated metal hydroxide;
Antistatic - various types of antistatic agents;
Conductive - carbon (carbon black, graphite, carbon fiber, carbon nanotubes), metal fibers and metal powder, metal oxides;
Magnetic - ferrite magnetic powder, rare earth magnetic powder including samarium cobalt type (SmCo5 or Sm2Co17), neodymium-iron-boron type (NdFeB), samarium-iron-nitrogen type (SmFeN), aluminum-nickel;
Thermal conductivity - metal fibers and metal powders, metal oxides, nitrides and carbides; carbon materials such as carbon black, carbon fibers, graphite and carbon nanotubes; semiconductor materials such as silicon and boron;
Heat-resistant - glass fibers, inorganic fillers, heat-resistant agents such as substituted maleimides and beta crystalline nucleating agents;
Transparent - nucleating agents, α crystalline nucleating agents for PP, sorbitol series of the best results;
Wear-resistant - graphite, molybdenum disulfide, copper powder and other cobalt magnetic powder three categories
Insulation - calcined kaolin;
Barrier - mica, montmorillonite, quartz and so on.

Plasticizers
A class of low volatile organic compounds that can be miscible with polymers to a certain extent, they are able to reduce the viscosity of the polymer melt as well as the glass transition temperature and elastic modulus of the product. The mechanism of action is based on the weakening of the gravitational forces between the polymer molecular chains by the plasticizer molecules.

Heat Stabilizers
The main function is to prevent thermal degradation during processing, but also to prevent products from aging during long-term use. Heat stabilizers for PVC and vinyl chloride copolymers are used in large quantities. The main categories of heat stabilizers are salt-based lead salts, fatty acid soaps, organotin, organic auxiliary stabilizers and compound stabilizers.

Antioxidants
In the rubber industry, antioxidants are still customarily called antioxidants. Antioxidants for plastics are mainly phenolic main antioxidants and thiodipropionate, phosphite and other auxiliary antioxidants.

Light stabilizers
Plastics and other polymers absorb UV light energy, which can trigger an auto-oxidizing reaction and lead to degradation. This process is known as photo-oxidation or photoaging, and substances that can inhibit or delay this process are called light stabilizers.

Flame Retardants
Most plastics are flammable. With the wide application of plastics in construction, furniture, transportation, aviation, aerospace, electrical appliances, etc., improving the flame retardancy of plastics has become a very urgent issue.

Foaming agent
Divided into physical foaming agent and chemical foaming agent two categories. Chemical blowing agent is divided into inorganic blowing agent and organic blowing agent. They are in the polymer due to heat gasification or decomposition of gas, so that the polymer material to produce bubbles, so named.