Why Are Chemicals Stored In Plastic Containers?

8th November 2017

Chemicals, Company News

Why are chemicals stored in plastic containers?

Have you ever wondered why plastic containers are most commonly used for storing chemicals? It goes well beyond the variety of shapes and sizes they come in, or the environmental benefits they offer, although these are major bonuses.

Storing a chemical in the right container is the first way to ensure safety when handling strong acids and bases. A material that is likely to react with the chemical it holds, like a metal container, or break easily when dropped, like a glass container, isn’t going to be suitable for a substance like nitric acid, for example.

This why there are a variety of plastic materials used for storing acids and bases, so that each container can accommodate the unique properties of individual chemicals

Plastic vials of deionised water

Three Types of Plastic Containers

  1. Polyethylene (PE)

Polyethylene was first synthesised in Germany in 1898 when chemist Hans von Pechmann prepared it by complete accident. Since then, PE has become the most common and widely produced plastic in the world. It can be used in three forms, which demonstrate its versatility and ability to be incorporated into a wide range of applications.

LDPE (Low Density Polyethylene) is used to produce grocery bags. HDPE (High Density Polyethylene) has a higher crystalline structure, and can be recognised in your garbage bins and drainpipes. Ultrahigh Molecular Weight PE has higher performance applications, and is even used to produce bulletproof vests. With this in mind, it’s easy to see why PE is an ideal material to store chemicals in.

High Density Polyethylene creates corrosion resistant plastic containers, and its thermoplastic properties means that it can withstand temperatures, be cooled, and reheated again without any significant degradation.

The diversity of PE variants means that it is compatible with most strong acids and bases. Like with the bulletproof vests, PE is noted for its high impact strength. This makes it perfect for storing chemicals as it is very difficult to break, and therefore decreases the risk of chemical spills.

Find out more about what Polyethylene is capable of here!

  1. Polymethylpentene (PMP)

PMP is a transparent, thermoplastic polymer with high chemical resistance. But this complex polyolefin is actually the backbone to a very familiar object: beakers.

We’ve all used beakers in Science class, and have at some time or another dropped one on the floor. Often, they do not break, and this is because classrooms have made the shift from glass beakers to Polymethylpentene beakers.

While PMP is more brittle than its cousin, Polyethylene, it can be designed to be shatterproof. Its clear material means that substances can be seen easily, and it’s also highly resistant to corrosion. PMP makes perfect plastic containers for storing both acids and bases of different strengths.

  1. Teflon

Another accidental discovery by Roy Plunkett in 1938, Polytetrafluoroethylene (PTFE) is the fluoropolymer behind Teflon. It is characterised by its hydrophobic properties, which means that most substances are unable to stick to Teflon. This is why it is able to resist corrosion from many chemicals, such as sulphuric acid and nitric acid.

The slippery material means that PTFE will not absorb the chemicals it comes into contact with, and the strength of its carbon-fluorine bonds makes it non-reactive. For these reasons, Teflon-coated plastic containers are ideal for storing a wide variety of acids and bases.

But what about glass containers?

While glass containers do have their advantages, such as being nonporous and chemically inert, they have major drawbacks in the fact that they break easily. Not only would this create sharp glass fragments, it would also expose potentially harmful and corrosive chemicals.

In addition, not all acids and bases are safe to store in glass containers, meaning that its versatility is very limited. Hydrofluoric acid, for example, has the propensity to eat through glass (SiO2); it contains the element Fluorine which can dislodge oxygen from its bond. On the other hand, Hydrofluoric acid can be stored in Polyethylene, Polymethylpentene, and Teflon containers, showing how plastic containers are the ideal material for containing chemicals.

Ampoule glass and plastic containers

ReAgent now supply ampoule containers for medical training. To see how we do this, watch the video on our blog!

At ReAgent, we consider the packaging of our products as an important part of the manufacturing process.  We have a wide range of containers to suit every unique chemical, including:

  • Glass ampoules and bottles (coated with plastic to retain the product should the glass break)
  • High Density Polyethylene (HDPE) bottles and jerrycans
  • Opaque HDPE containers to protect chemicals sensitive to light
  • Industrial bulk containers

By having a diverse range of containers, ReAgent can accommodate the unique blends of chemicals we manufacture. To find out more about our first-class packaging materials, click here for a more in-depth description.

In the packaging business since 1977, our expertise and customer-centred approach mean that we are dedicated in providing the packaging that is right for the job, and right for you.

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