HDPE CNOOC 5121B

[Full English Name] High Density Polythene

PE material

HDPE

[Full Chinese Name] High density polyethylene

Low pressure ethylene

[Composition monomer] Ethylene

【 Basic characteristics 】 High density polyethylene is an opaque white waxy material with a specific gravity lighter than water, ranging from 0.941 to 0.960. It is soft and tough, but slightly harder than LDPE and can also elongate slightly. It is non-toxic and odorless.

[Burning characteristics] Flammable, can continue to burn after leaving the flame. The upper end of the flame is yellow and the lower end is blue. It will melt during combustion, with liquid droplets and no black smoke emitted. At the same time, it emits the odor of paraffin burning.

【 Main advantages 】 Acid and alkali resistance, organic solvent resistance, excellent electrical insulation, and the ability to maintain a certain degree of toughness at low temperatures. The mechanical strength such as surface hardness, tensile strength, and rigidity are higher than LDPE, close to PP, and tougher than PP, but the surface smoothness is not as good as PP.

【 Main Disadvantages 】 Poor mechanical performance, poor breathability, easy deformation, aging, brittleness, lower brittleness than PP, easy stress cracking, low surface hardness, and easy scratching. Difficult to print, surface discharge treatment is required during printing, electroplating is not allowed, and the surface is dull.

【 Application 】 Used for extruding packaging films, ropes, woven bags, fishing nets, water pipes; Injection molded low-end daily necessities and casings, non load bearing components, rubber boxes, turnover boxes; Extruded blow molded containers, hollow products, bottles.

Injection molding technology: HDPE has countless applications, ranging from reusable thin-walled beverage cups to 5-gsl cans, consuming 1/5 of domestically produced HDPE. The injection molding grade generally has a melt index of 5-10, with grades with lower toughness and higher processability. Uses include thin-walled packaging materials for daily necessities and food; Resilient and durable food and paint cans; High resistance to environmental stress cracking applications, such as small engine fuel tanks and 90 gal garbage cans.

The general melting point of HDPE is 142 ℃, and the decomposition temperature is 300 ℃; The adjustable range of injection temperature is relatively large. During injection molding, the general operating temperature is between 180 ℃ and 230 ℃; As it is an olefinic plastic, it does not absorb water and does not require drying during production. However, for product quality, it can be dried at 60 ℃ for 1 hour to discharge floating water; Polyethylene has a high melt viscosity and a low flow length ratio, and thin-walled products may lack adhesive. Therefore, the gate and runner are relatively large; The product is prone to static electricity and the surface is easily absorbent. The shrinkage rate is 16 ‰; The overflow value is 0.05mm.

Main uses

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High density polyethylene resin can be used to form plastic products through injection, extrusion, blow molding, and rotational molding methods. By using injection molding, various types of containers, industrial accessories, medical supplies, toys, shells, bottle stoppers, and covers can be formed. Various hollow containers, ultra-thin films, etc. can be formed by blow molding. Extrusion molding can be used to form pipes, stretching strips, strapping tapes, single wires, wire and cable sheaths, etc.

In addition, it can also be used to shape decorative panels, blinds, synthetic wood, synthetic paper, synthetic films, and formed calcium plastic products for construction [1]