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The Composition Of The Plastic
- Sep 05, 2018 -

Ingredient Description: The plastic we usually use is not a single ingredient, it is made up of many materials.

Among them, polymer (or synthetic resin) is the main component of plastics, in addition, in order to improve the performance of plastics, but also to add a variety of auxiliary materials in the macromolecule, such as fillers, plasticizers, lubricants, stabilizers, colorants, antistatic agents, to become a good performance of plastic. Plastic additives, also known as plastic additives, are polymers (synthetic resins) for the molding process to improve their processability or to improve the performance of the resin itself is not sufficient to add some of the compounds. For example, in order to reduce the molding temperature of polyvinyl chloride resin, make the product soft and add plasticizer, and for the preparation of light weight, anti-vibration, heat insulation, acoustic foam and to add foaming agent; some plastics have a thermal decomposition temperature very close to the molding process temperature and cannot be molded without a thermal stabilizer.

Therefore, plastic additives in the plastic molding process occupies a particularly important position.

Synthetic resin: Synthetic resin is the most important component of plastics, and its content in plastics is generally 40%~100%. Because of the large content, and the nature of the resin often determines the nature of the plastic, so people often think of resin as a synonym for plastics. For example, polyvinyl chloride resin and polyvinyl chloride plastic, phenolic resin and bakelite confused. In fact, resins and plastics are two different concepts. Resin is an unprocessed raw polymer that is used not only for the manufacture of plastics, but also for paints, adhesives and synthetic fibres.

Plastic, in addition to a very small portion of 100% of the resin, the vast majority of plastic, in addition to the main components of the resin, but also need to add other substances.

Filler: Fillers are also called fillers, which increase the strength and heat resistance of plastics and reduce costs. For example, the addition of wood powder to phenolic resin can greatly reduce the cost, making bakelite one of the cheapest plastic, but also can significantly improve the mechanical strength. Filler can be divided into two types of organic fillers and inorganic fillers, such as wood powder, rags, paper and a variety of textile fiber, such as glass fiber, diatomite, asbestos, carbon black and so on.

The filler in the plastic content is generally controlled under 40%.

Plasticizer: Plasticizers, or plasticizing agents, can increase the plasticity and softness of plastics, reduce brittleness and make plastic easy to process. Plasticizer (plasticizing agent) is generally miscible with the resin, non-toxic, odorless, light, heat stabilized high boiling point organic compounds, the most commonly used phthalate esters.

For example, when the production of PVC, if the addition of more plasticizers can be soft PVC, if not added or less plasticizer (dosage <10%), the hard PVC.

Stabilizing Agent: Stabilizer mainly refers to keep polymer plastic, rubber, synthetic fibers and other stable, to prevent its decomposition, aging reagents. In order to prevent the processing and use of synthetic resins by the role of light and heat decomposition and destruction, prolong the service life, to add stabilizers in the plastic. Commonly used are stearic acid salt, epoxy resin and so on.

The dosage of stabilizer is generally 0.3~0.5% of plastic.

Coloring Agent: Coloring agents can make plastic with a variety of bright, beautiful colors. Commonly used organic dyes and inorganic pigments as coloring agents. The natural color of synthetic resins is mostly white translucent or colorless and transparent.

Colorants are often used in industrial production to increase the color of plastic products.

Lubricant: The role of the lubricant is to prevent the plastic from sticking to the metal mold while forming, and to make the plastic surface smooth and beautiful.

The commonly used lubricants are stearic acid and calcium magnesium salts.


Prevent the plastic in the heating molding or in the high temperature use process of heating oxidation, and make the plastic yellow, crack and so on. In addition to the above additives, the plastic can also be added flame retardants, foaming agents, antistatic agents, conductive agents, magnetic agents, compatibility agents.

To meet the different use requirements.

Antistatic Agent: Plastic is an excellent insulator, so it is easy to carry static electricity, and antistatic agents can give plastic to light to medium conductivity, which can prevent the accumulation of electrostatic charge on the product.