HDPE – High Density Polyethylene
High-density polyethylene (HDPE) or polyethylene high-density (PEHD) is a polyethylene thermoplastic made from petroleum. It takes 1.75 kilograms of petroleum (in terms of energy and raw materials) to make one kilogram of HDPE. HDPE is commonly recycled, and has the number "2" as its recycling symbol. The mass density of high-density polyethylene can range from 0.93 to 0.97 g/cm3. Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength than LDPE. The difference in strength exceeds the difference in density, giving HDPE a higher specific strength. It is also harder and more opaque and can withstand somewhat higher temperatures (120 °C/ 248 °F for short periods, 110 °C /230 °F continuously).
In 1953, Karl Ziegler of the Kaiser Wilhelm Institute (renamed the Max Planck Institute) and Erhard Holzkamp invented high-density polyethylene (HDPE). The process included the use of catalysts and low pressure, which is the basis for the formulation of many varieties of polyethylene compounds. Two years later, in 1955, HDPE was produced as pipe. For his successful invention of HDPE, Ziegler was awarded the 1963 Nobel Prize for Chemistry.
Ineos and LyondellBasell are the leading technology licensors for HDPE. LyondellBasell, SABIC, Chevron Phillips, Dow Chemical, Ineos, ExxonMobil, IPIC group, NPC Iran, SINOPEC group, Total PC, PetroChina Group, Braskem Group and Reliance Industries Ltd are some of leading producers of HDPE. The nameplate plant size capacity has risen from 33 MMT in 2006 to 42 MMT in 2011.
The global capacity of HDPE was 42MMT in 2011 and demand is 35 MMT. The capacity is expected to increase to 52 MMT in 2016 with demand reaching 45 MMT. In India the total HDPE capacity is expected to reach 3090 KTA by 2016-17 and OPAL has planned capacity expansion to 720 KTA by 2016-17 followed by GAIL 700 KTA, HPL 550 KTA, Reliance Industries Ltd 490 KTA, IOCL 475 KTA and BPCL Assam GC 155 KTA.
HDPE price touched its lowest level in last five years in Nov’08 – 701$/MT-SE Asia prices, while in May’12 HDPE prices touched 1354$ MT corresponding to Crude 107.31 $/Barrel and Naphtha 886 $/MT. The demand for HDPE is rising from other developing countries such as that of China, India and Brazil. Asia Pacific is expected to emerge as the leading region with a demand of more than 60% of the global demand for HDPE. Dow, Westlake, Braskem Idesa, Nova, Chevron Phillips, Borouge and Shell have announced HDPE capacity expansion plans
High-density polyethylene (HDPE) is principally used for the manufacture of high-performance pipe, blow-molded household and industrial bottles, oil bottles, injection-molded food containers, consumer durables and disposable goods and film goods such as grocery sacks and merchandise bags. HDPE finds its application in Raffia, Blow Moulding, Film, Pipes and Injection Moulding. Consumption wise it is in order of HD-Film GP Blow Moulding, Raffia, Pipe, have the major share. Large and Medium Blow Moulding containers, Pipe, General Purpose BM containers are currently the leading growth sectors.