A thermoplastic polyolefin made by ethylene copolymerization is high-density polyethylene (HDPE). HDPE was first made available in 1956, although it hasn't yet achieved a mature state. New markets and uses for this all-purpose material are continually being developed.
Since there are no branched chains on the molecular chain in Ziegler Natta polymerization, which produces HDPE most frequently, the molecular chain is structured uniformly and has a high density. Ethylene is employed as raw material and oxygen or organic peroxide as an initiator in a low-pressure tube or kettle reactor in this process. Buy HDPE Pipe Fittings from Petron.
Characteristics of HDPE Materials
Basic Characteristics
With a specific gravity of 0.941 to 0.960, HDPE is a white, opaque waxy substance that is lighter than water. It may be extended and is flexible and ductile, yet it is a little tougher than LDPE. It has no flavor and is non-toxic.
Combustion Characteristics
It is combustible and can keep burning even after the fire has been extinguished. The flame has a blue bottom end and a yellow higher end. It will dissolve while burning, pouring liquid instead of producing black smoke. It also emits the scent of burning paraffin at the same time.
Key Advantages
Excellent electrical insulation, acid and alkali resistance, resistance to organic solvents, and ability to retain some hardness at low temperatures. Although the surface smoothness is not as excellent as PP, the surface hardness, tensile strength, stiffness, and other mechanical strengths are greater than LDPE, comparable to PP, and tougher than PP.
Main Disadvantages
Low surface hardness, low surface hardness, easy scratching, low surface hardness, quick stress cracking, poor mechanical characteristics, poor air permeability, easy deformation, easy aging, easy brittleness, brittleness lower than PP, and easy deformation. Printing is tricky. Electroplating is not permitted, surface discharge treatment is necessary during printing, and the surface is dull.
Application
used to extrude water pipe, rope, weaved bags, fishing nets, and packaging film; Extrusion blow molding containers, hollow goods, and bottles; injection molding low-grade daily essentials and shell, non-load-bearing components, rubber boxes, and turnover boxes.
Injection Molding Process
One-fifth of the HDPE manufactured in China is used in a variety of products, from 5-gsl cans to reusable thin-walled beverage cups. Injection molding typically has a melt index between 5 and 10, low toughness, and good flowability. Thin-walled packaging for food and everyday necessities is also used. Tough and durable paint cans and garbage cans with high resistance to environmental stress cracking are also used.
The average HDPE has a melting point of 142 °C and a decomposition temperature of 300 °C; it has a wide temperature range that may be adjusted for injection. The typical service temperature for injection molding is between 180 and 230 °C; because it is an olefinic plastic, it does not absorb water and does not require drying during manufacturing. Although it can be dried at 60 °C for an hour to remove floating water for the sake of product quality, the thin-walled goods might not have glue because polyethylene melts with high viscosity and has a low flow length ratio. Consequently, the gate and runner are substantial; Static electricity can easily be carried by the product, and Angstrom can be readily absorbed by the surface. The overflow value is 0.05mm, and the shrinkage rate is 16. Buy high-quality HDPE Pipe Fittings online only at Petron Thermoplast.
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