Why is Low Density Polyethylene so useful in plastic manufacturing?

August 20, 2018

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Polyethylene a material that we rely on a lot for plastic manufacturing here at Excelsior. If you’ve been following our blog recently, you’ll have already seen our recent piece on High Density Polyethylene. Its counterpart, Low Density Polyethylene, or LDPE, is another one of the core materials we often use for our roto moulding processes, so we thought it made sense to give it a bit of spotlight, too! Here’s why so many of our customers find it so useful, and why it might be worth considering for your own plastic product.

A quick overview of Low Density Polyethylene

If you’ve got any previous experience with the plastic manufacturing industry at all, there’s a good chance you’ll have heard of LDPE. Like its counterpart, HDPE, it’s a thermoplastic. This means it’s able to change its shape when subjected to heat, and change back again repeatedly, all without losing its overall strength or structure.

Also like HDPE, LDPE is semi-crystalline. Now, we won’t go too much into the chemistry behind it all, but basically LDPE has a less compact molecular structure than HDPE. This means it has a lower density, a lower tensile strength, and therefore greater flexibility than its counterpart, which makes it useful for a huge number of applications. In short, LDPE has a lot of characteristics and strengths, but a lot of them can be traced back to its soft, flexible and versatile nature.

Advantages of Low Density Polyethylene

Flexible, with a low tensile strength

Essentially, this means that LDPE can withstand a lot of stretching before it actually breaks, which makes it fantastically useful for applications like plastic bags, bin bags and other plastic films.

Moisture resistant

This is another key characteristic which makes it so handy for storage containers. Obviously, you won’t want to be taking the bin bags out if liquid is capable of leaking through it! It’s also for this reason that LDPE is also used for chemical tank linings, water pipes and squeeze bottles.

Impact resistant

Despite its low tensile strength, LDPE has a surprisingly high impact resistance, which makes it usefully durable. It’s another reason why it’s so handy for water pipes and drinks containers. Especially drinks containers geared towards young children, who tend to have a habit of throwing them or dropping them for some distance!

Chemical resistance

Like HDPE, the high chemical resistance of LDPE means there are a number of food grade varieties available, making it well suited for food packaging, single-use drinks cartons and similar applications in the retail food industry. It can also be used for hygienic work surfaces in offices, too.

High temperature resistance

Its status as a thermoplastic means it retains its shape well between the temperatures of -40C to 90C. For most applications, they’re pretty extreme temperature ranges, so not normally something our average customers should have to worry about!

Poor conductor of electricity

Like all plastics, LDPE is more or less shock-proof. Coupled with its flexibility, that means it’s commonly used for applications such as insulation on electrical wires and cables.

Cost-effective, economical and widely recyclable

These final three advantages collectively make LDPE hugely attractive as a plastic manufacturing material to customers across a range of sectors. It takes very little energy and investment to produce, which makes it fantastic for mass production and large product batch runs, and the ease with which it can be recycled means that it often manages to sidestep the environmental concerns which are making so many headlines at the moment.

As we touched on above, it’s just one of several materials we use for our rotomoulding processes here at Excelsior. Feel free to take a look through our plastic manufacturing case studies to find out what we’ve achieved for previous clients, or alternatively give us a call on 0161 765 2010, and find out how we can make your plastic product a reality!