+86-13706562320
s01 img

News

Plastic mold structure

2022-11-25
Share:
The plastic mold structure mainly includes a female mold with a variable cavity composed of a female mold combination substrate, a female mold component and a female mold combination card board, and a male mold with a variable core composed of a male mold combination substrate, a male mold component, a male mold combination card board, a cavity cutting component and a side section combination board.
In order to improve the performance of plastics, various auxiliary materials such as fillers, plasticizers, lubricants, stabilizers, colorants, etc. should be added to the polymer to become plastics with good performance.

1. Synthetic resin is the main component of plastics, and its content in plastics is generally 40%~100%. Because of the large content and the nature of resin, people often regard resin as a synonym of plastic. 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 make plastics, but also raw materials for coatings, adhesives and synthetic fibers. In addition to a few plastics containing 100% resin, most plastics need to add other substances besides the main component resin.

2. Filler
Fillers, also called fillers, can improve the strength and heat resistance of plastics and reduce costs. For example, the addition of wood flour to phenolic resin can greatly reduce the cost, making phenolic plastic one of the cheapest plastics, and significantly improve the mechanical strength. Fillers can be divided into organic fillers and inorganic fillers. The former includes wood powder, rags, paper and various fabric fibers, while the latter includes glass fiber, diatomite, asbestos, carbon black, etc.

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

4. Stabilizer
In order to prevent the synthetic resin from being decomposed and destroyed by light and heat in the process of processing and use, and to extend its service life, a stabilizer should be added to the plastic. Stearate and epoxy resin are commonly used.

5. Colorant
Colorants can make plastics have various bright and beautiful colors. Organic dyes and inorganic pigments are commonly used as colorants.

6. Lubricant
The function of the lubricant is to prevent the plastic from sticking to the metal mold during molding, and to make the plastic surface smooth and beautiful. Common lubricants include stearic acid and its calcium magnesium salts. In addition to the above additives, flame retardant, foaming agent, antistatic agent, etc. can also be added into the plastic.