Home > Knowledge > Content
How to distinguish between blow molding, injection molding and film level HDPE?
- Jul 16, 2018 -

How to distinguish between blow molding, injection molding and film level HDPE?


Generally, according to the melting index value, blow blown and film grade HDPE melt fingers will be smaller, usually below 2. The melt index of injection will be greater than 2 or even a few dozen.


High Density Polyethylene (referred to as "HDPE") is a high crystallinity, non-polar thermoplastic resin. The surface of the original HDPE is milky white with a translucent appearance in the thin section. PE has excellent resistance to most living and industrial chemicals.


HDPE is a high degree of crystallinity and non-polar thermoplastic resin.


High density polyethylene is a non-toxic, odorless, odorless white particle with a melting point of about 130 C and a relative density of 0.941~0.960. It has good heat resistance and cold resistance, good chemical stability, high rigidity and toughness, and good mechanical strength.


Dielectric properties and environmental stress cracking resistance are also good. The melting temperature is 120~160 C. For larger molecules, it is suggested that the melting temperature range is between 200~250 C.


High density polyethylene (HDPE) is a white powder granular product. It is nontoxic and tasteless.


The density is in the range of 0.940 to 0.976 g/cm3.


The crystallinity is 80% to 90%, the softening point is 125~135, and the use temperature is up to 100.


The hardness, tensile strength and vermicular properties are superior to those of low density polyethylene, and the wear resistance, electrical insulation, toughness and cold resistance are all Better, but a little worse than low density insulation; good chemical stability, under room temperature, insoluble in any organic solvent, acid, alkali and salt corrosion, low permeability of water vapor and air, low water absorbability, poor aging resistance and low environmental cracking resistance, especially low density polyethylene, especially Thermal oxidation will cause its performance to decrease.


Therefore, resins should be added with antioxidants and UV absorbers to improve the deficiencies. The thermal deformation temperature of HDPE film under stress is low, which should be paid attention to when applied.