What are the plastic mold structures

The plastic mold structure mainly includes a concave mold with a variable cavity composed of a concave mold composite base plate, a concave mold component and a concave mold composite clamp plate, and a convex mold with a variable core composed of a convex mold composite base plate, a convex mold component, a convex mold composite clamp plate, a cavity cutting component and a side cutting composite plate.
In order to improve the performance of plastics, a variety of auxiliary materials, such as fillers, plasticizers, lubricants, stabilizers, colorants, etc., must be added to the polymer to become a plastic with good performance.

1. Synthetic resin is the most important component of plastics, and its content in plastics is generally 40%~100%. Because of its large content and the nature of resin often determines the nature of plastics, people often regard resin as a synonym for plastics. For example, PVC resin and PVC plastic, phenolic resin and phenolic plastic are confused. In fact, resin and plastic are two different concepts. Resin is a kind of raw polymer, which is not only used to manufacture plastics, but also used as raw materials for coatings, adhesives and synthetic fibers. In addition to a small part of plastics containing 100% resin, the vast majority of plastics need to add other substances in addition to the main component resin.

2. Filler, also known as filler, can improve the strength and heat resistance of plastics and reduce costs. For example, adding wood powder into phenolic resin can greatly reduce the cost, make phenolic plastic one of the cheap plastics, and also significantly improve the mechanical strength. The fillers can be divided into organic fillers and inorganic fillers. The former is wood powder, rags, paper and various textile fibers, and the latter is glass fiber, diatomite, asbestos, carbon black, etc.

3. Plasticizer Plasticizer can increase the plasticity and softness of plastics, reduce brittleness, and make plastics easy to process. Plasticizers are generally high boiling point organic compounds that are miscible with resins, non-toxic, odorless, light and heat stable, and phthalates are commonly used. For example, in the production of PVC plastics, if more plasticizers are added, soft PVC plastics can be obtained; if no or less plasticizers are added (dosage<10%), rigid PVC plastics can be obtained.

4. Stabilizer In order to prevent the decomposition and destruction of synthetic resin by the action of light and heat during processing and use, and to extend the service life, stabilizer should be added to the plastic. Common ones include stearate, epoxy resin, etc.

5. Colorants Colorants can make plastics have a variety of bright and beautiful colors. Organic dyes and inorganic pigments are often used as colorants.

6. The role of lubricant is to prevent plastic from sticking to metal mold during molding, and to make the surface of plastic smooth and beautiful. The commonly used lubricants include stearic acid and its calcium and magnesium salts. In addition to the above additives, flame retardants, foaming agents and antistatic agents can also be added to the plastics.