4 Most Essential Differences Between HDPE And PET Plastics

4 Most Essential Differences Between HDPE And PET Plastics

In Singapore, plastic containers are a popular choice for many food and beverage (F&B) businesses. Besides being safe and affordable, plastic containers for food are also generally sustainable and long-lasting. As such, it comes as no surprise that plastic remains one of the most preferred materials for food packaging to this day. However, did you know that there are actually different types of plastic?

Among the most common plastic types used for making food containers and other packaging materials are HDPE and PET plastics. HDPE basically stands for high-density polyethylene and is a filmy plastic that is highly resistant to impacts, heat, corrosion, and corrosion. On the other hand, PET stands for polyethylene terephthalate and is a clear plastic that can endure temperatures up to 145ºF. Read on to learn more about the differences between HDPE and PET plastics.

1. Temperature Range 

Although both HDPE and PET plastics are relatively resistant to heat, HDPE usually has a higher melting point than PET. HDPE plastics can withstand temperatures as high as 160ºF. They also often have a lower cold brittleness temperature and can resist a maximum cold temperature of -50ºF. In comparison to this, PET plastics can typically only handle a maximum cold temperature of -40ºF.

2. Gas Barrier 

The gas barrier or Water Vapor Transmission Rate (WVTR) of a plastic is usually measured in g-mil/100in. 2/24hr, which is indicative of the penetration of vaporised water through the barrier of the plastic. Basically, a lower WVTR signifies that the packaging material can protect its content from moisture exposure for a longer period of time. Generally, HDPE plastics have a 0.5 WVTR, while PET plastics come with a 2.0 WVTR.

3. Stress Crack Resistance

Stress cracking is a common problem in plastic materials that can damage the contents of the packaging. A stress crack can be either an external or internal crack that arises as a result of tensile stresses. When it comes to HDPE plastics, stress cracks often happen due to environmental chemicals that attack this petroleum-based and semi-crystalline plastic.

Basically, when the plastic polymer’s molecular weight increases, crystallinity reduces and enhances resistance to stress cracking. In comparison to HDPE plastics, PET plastic bottles and food containers are known to have a higher resistance to stress cracking. 

4. Recyclability 

Both HDPE and PET plastics can be recycled. However, before recycling them, HDPE and PET plastics must be separated because the processes that they require to break down and reform the compounds are different. Usually, you can find a triangular label containing a number inside on the base of each plastic type.

This number indicates the recycling rating of the plastic material. HDPE plastics have a recycle rating of 2, which means that they can be recycled and reused up to 2 times before disposal. On the other hand, PET plastics have a recycle rating of 1, which means that they are designed for single use only.


There are various factors that make HDPE plastics and PET plastics significantly different from each other. With that said, both of these plastic materials are very durable and functional for a wide variety of applications. Usually, the best choice of plastic depends on the kinds of products you need to package or ship. If you are specifically running an F&B business, PET plastics are your best choice for a high-quality and sustainable packaging. 

For the most reliable and excellent plastic food packaging in Singapore, Supply Smiths is the trusted plastic container supplier you can count on! We have a great selection of top-notch plastic food containers that are ideal for packaging and storing your different food products. Apart from this, we also offer a variety of other amazing food packaging solutions, including paper lunch boxes, bento boxes, platter trays, standing zipper pouches, and cake boxes. 

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