What are the characteristics of plastic products?
1 Plastic products are generally lighter, and dense hair is slightly greater than the density of water; Polyethylene and polypropylene are less dense than water. 2 Plastic products are resistant to acid, alkali, corrosion. It has better insulation, thermal insulation and sound insulation. Plastic parts in mechanical equipment, such as bearings and gears, work to reduce noise, do not conduct heat, and wear resistant. Some plastics have excellent transparency and can replace fragile glass on special occasions.
1. 41 What are the methods of plastic moulding?
There are many methods for plastic molding products: general thermoplastic plastics can be extruded by extruder equipment, blown molding, hollow molding, press molding by extruder equipment, injection molding by injection molding machine equipment, and flow. The machine is used to extend the film, in addition, It is also possible to perform secondary molding such as foaming molding, thermal molding and vacuum molding. Thermosetting plastics are molded, laminated, transferred molded, and reacted. Injection molding and casting molding.
1. 42 What is the classification of plastic products by use?
Plastics can be divided into general plastics(such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, etc.), engineering plastics(such as polyamide, polycarbonate, polyformaldehyde, thermoplastic polyester, etc.), special engineering plastics(such as polyphenylthioether, polyimide, fluorine plastics) according to their comprehensive properties Wait).
According to its shape, plastic products can be divided into thin films, sheet materials, plates, profiles, pipes, silk, ropes, belts, artificial leather, synthetic leather, injection molding products, molded products, laminated products and so on. According to the purpose, it can be divided into agricultural plastic products, construction plastic products, and plastics for packaging.
Products, electronic appliances plastic products, oral plastic products, military plastic products, automotive plastic products.
1. 43 What is a plasticizer?
Plasticizers are mostly high boiling point liquid vinegar. Adding a certain proportion to the resin can change the properties of the resin, such as increasing the softness of the plastic, reducing the viscosity of the melted material, and making the resin easy to process and form.
What are the effects of adding polyvinyl chloride resins to products in different proportions?
Plasticizer added to PVC resin, the greater the score added, the softer the plastic product: when adding a minimum of 5 %, the plastic product is hard; When the amount of addition is 15 % to 5 %, the plastic product is semi-rigid; When the human volume is greater than 25 %, the plastic product is
Soft; When the amount of plasticizer added is 5 % to ISI %, anti-plasticizing phenomenon will occur, affecting the quality of the product, and should be prevented as much as possible when preparing.
1. What kinds of plasticizers are commonly used? What's the acronym code?
Commonly used plasticizers are: dioctyl phthalate(DOP); Dibutyl phthalate(DBP); Dihexyl adipate(DOA); Hydecic acid-hexyl Ester(DOS); Trimethylphosphate(TCP); Triphenyl phosphate(TPP); Paraffins(P-CI); Petroleum esters(T-50); Alkyl sulfonic acid(M-50), polyethylene glycol(PEG); TETM: Trin-butyl citrate(TBC) et al..
1. What conditions should we consider when choosing plasticizers in the formula of plastic products?
1 We should pay attention to the selection of plasticizers that are compatible with PVC resins, have low volatility, and are easy to migrate and exudate.
2 Choose the plasticizer that can reduce the PVC tree and its melting point, reduce its processing temperature, and facilitate the formation of plastic products.
3 Choose plasticizer with high plasticizer efficiency