HDPE is a high degree of crystallinity, non-polar thermoplastic resin. High density polyethylene non-toxic, tasbess white particles, odorless, melting point 130 ℃, relative density is 0.941~0.960. It has good heat resistance and cold resistance, good chemical stability, also has high rigidity and toughness, good mechanical strength. Dielectric properties, resistance to environmental stress cracking resistance is also good. The melting temperature of 220~260 ℃. For larger molecules of the material, suggest that melting temperature of 200~250 ℃. High density polyethylene is a kind of white powder granular products, non-toxic, tasbess, density of 0.940 ~ 0.976 g/cm3 range; the crystallinity of 80% ~ 90%, softening point of 125 ～ 135 ℃, temperature can reach 100 ℃; hardness, tensile strength and creep resistance is better than that of low density polyethylene; wear resistance, electrical insulation, toughness and cold resistance are good, but with low density insulating property slightly worse; good chemical stability, under the condition of room temperature, insoluble in any organic solvent, acid, alkali and salt corrosion; permeability to water vapor and air film is small, the water absorption of aging resistance perbance is poor, low; environmental stress cracking resistance as low density polyethylene, especially the thermal oxidation will make the perbance drop, so, resin added antioxidant and UV absorbent to improve this deficiency. High density polyethylene film under stress of hot debation temperature is low, should pay attention to this point application.

高密度聚乙烯通常使用Ziegler-Natta聚合法制造，其特點(diǎn)是分子鏈上沒有支鏈，因此分子鏈排布規(guī)整，具有較高的密度。該過程在管式或釜式低壓反應(yīng)器中以乙烯為原料，用氧或有機(jī)過氧化物為引發(fā)劑引發(fā)聚合反應(yīng)。

High density polyethylene usually use Ziegler-Natta manufacturing polymerization, which is characterized by no branched chains, therefore molecular chain arrangement of regular, have a higher density. In the process of tubular or kettle type low voltage reactor to ethylene as raw material, with oxygen or organic peroxides as initiators and polymerization.

高密度乙烯屬環(huán)保材質(zhì)，加熱達(dá)到熔點(diǎn)，即可回收再利用。須知塑膠原料可大分為兩大類：“熱塑性塑膠”（Thermoplastic）及“熱固性塑膠”（Thermosetting），“熱固性塑膠”是加熱到一定溫度后變成固化狀態(tài)，即使繼續(xù)加熱也無法改變其狀態(tài)，因此，有環(huán)保問題的產(chǎn)品是“熱固性塑膠”的產(chǎn)品（如輪胎），并非是“熱塑性塑膠”的產(chǎn)品（如 塑膠棧板 注:棧板在港澳被稱為“夾板”)，所以并非所有“塑膠”皆不環(huán)保。

High density polyethylene belongs to the environmental protection material, heating to the melting point, can be recycled. For plastic materials can be divided into two categories: "thermoplastic plastic" (Thermoplastic) and "thermosetting plastic" (Thermosetting) ", thermosetting plastic" is a cured after heated to a certain temperature, even if the heating can not continue to change its state, therefore, environmental problem is the product of the "thermosetting plastic" products (such as tire), is not "thermoplastic plastic" products (such as plastic pallets note: pallets in Hong Kong and Macao is called "splint"), so not all the "plastic" are not environmental protection.