World Library  
Flag as Inappropriate
Email this Article

High-density polyethylene

Article Id: WHEBN0001911597
Reproduction Date:

Title: High-density polyethylene  
Author: World Heritage Encyclopedia
Language: English
Subject: J. Paul Hogan, Robert Banks (chemist), Low-density polyethylene, Barrel, Plastic
Collection: Plastics, Polyolefins
Publisher: World Heritage Encyclopedia

High-density polyethylene

HDPE has SPI resin ID code 2

High-density polyethylene (HDPE) or polyethylene high-density (PEHD) is a polyethylene thermoplastic made from petroleum. It is sometimes called "alkathene" or "polythene" when used for pipes.[1] With a high strength-to-density ratio, HDPE is used in the production of plastic bottles, corrosion-resistant piping, geomembranes, and plastic lumber. HDPE is commonly recycled, and has the number "2" as its resin identification code (formerly known as recycling symbol).

In 2007, the global HDPE market reached a volume of more than 30 million tons.[2]


  • Properties 1
  • Applications 2
  • See also 3
  • References 4
  • External links 5


HDPE is known for its large strength-to-density ratio.[3] The density of HDPE can range from 0.93 to 0.97 g/cm3 or 970 kg/m3.[4] 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.[5] 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). High-density polyethylene, unlike polypropylene, cannot withstand normally required autoclaving conditions. The lack of branching is ensured by an appropriate choice of catalyst (e.g., Ziegler-Natta catalysts) and reaction conditions.


HDPE pipe installation in storm drain project in Mexico

HDPE is resistant to many different solvents and has a wide variety of applications:

HDPE is also used for cell liners in subtitle D sanitary landfills, wherein large sheets of HDPE are either extrusion or wedge welded to form a homogeneous chemical-resistant barrier, with the intention of preventing the pollution of soil and groundwater by the liquid constituents of solid waste.

HDPE is preferred by the pyrotechnics trade for mortars over steel or PVC tubes, being more durable and safer. HDPE tends to rip or tear in a malfunction instead of shattering and becoming shrapnel like the other materials.

Milk jugs and other hollow goods manufactured through blow molding are the most important application area for HDPE, accounting for one-third of worldwide production, or more than 8 million tons. In addition to being recycled using conventional processes, HDPE can also be processed by recyclebots into filament for 3-D printers via distributed recycling.[7] There is some evidence that this form of recycling is less energy intensive than conventional recycling, which can involve a large embodied energy for transportation.[8][9][10]

Above all, China, where beverage bottles made from HDPE were first imported in 2005, is a growing market for rigid HDPE packaging, as a result of its improving standard of living. In India and other highly populated, emerging nations, infrastructure expansion includes the deployment of pipes and cable insulation made from HDPE.[2] The material has benefited from discussions about possible health and environmental problems caused by PVC and Polycarbonate associated Bisphenol A, as well as its advantages over glass, metal, and cardboard.

See also


  1. ^ Pipe materials.
  2. ^ a b "Market Study: Polyethylene HDPE". Ceresana Research. 
  3. ^ Thermoforming HDPE.
  4. ^ Typical Properties of Polyethylene (PE). Retrieved on 2011-12-30.
  5. ^ Compare Materials: HDPE and LDPE. Retrieved on 2011-12-30.
  6. ^ (2011-07-01). Retrieved on 2011-12-30.
  7. ^ Baechler, C.; Devuono, M.; Pearce, J. M. (2013). feedstock"Rap"Distributed recycling of waste polymer into Rep . Rapid Prototyping Journal 19 (2): 118.  
  8. ^ Kreiger, M. A.; Mulder, M. L.; Glover, A. G.; Pearce, J. M. (2014). "Life cycle analysis of distributed recycling of post-consumer high density polyethylene for 3-D printing filament". Journal of Cleaner Production 70: 90.  
  9. ^ The importance of the Lyman Extruder, Filamaker, Recyclebot and Filabot to 3D printing – VoxelFab, 2013.
  10. ^ Kreiger, M.; Anzalone, G. C.; Mulder, M. L.; Glover, A.; Pearce, J. M. (2013). "Distributed Recycling of Post-Consumer Plastic Waste in Rural Areas". MRS Proceedings 1492.  

External links

  • HDPE for Robotics
  • HDPE Advantages & Disadvantages
  • How to Recycle Plastic
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.