Image via Pexels

Materials and equipment represent critical choices for scientific and medical researchers. You want to make sure that your research project is within budget, but you also need to make sure that you are not jeopardizing the results in any way.

In this post, we’ll be focusing on test tubes, which play a critical role in chemical analysis and other research applications. In particular, polystyrene and polypropylene tubes. So, which is the best option for your project? Let’s take a look.

Polystyrene vs. Polypropylene: Advantages and Disadvantages

Polypropylene Tubes

Advantages

  • The material can be purchased relatively inexpensively.
  • They’re lightweight for easy storage.
  • The semi-crystalline nature of the material’s structure gives it a high maximum bending stress without damaging the tube.
  • When polypropylene tubes are placed side by side, there is a very low level of friction, which means very low levels of energy are produced when rubbing the tubes together.
  • Polypropylene is highly resistant to moisture, as well as to corrosion from many acids and alkalies.
  • The material features a high-impact strength while also resisting fatigue effectively.
  • They’re highly resistant to electricity, providing effective electrical insulation.
  • Repairing the material is easy and inexpensive, adding to the longevity of the tubes.

Disadvantages

  • They may not be suitable for higher temperature applications, due to its tendency to expand under extreme temperatures.
  • They are not suitable for prolonged outdoor usage or any experiments involving UV radiation, as there is a danger of UV degradation.
  • The material may be damaged by chlorinated solvents and aromatic compounds.
  • The material can fuel oxidation reactions.

Polystyrene Tubes

Advantages

  • Polystyrene is also inexpensive to purchase, even in larger quantities.
  • They’re also lightweight for easy storage.
  • The impact resistance of the material is high, especially in varieties graded for laboratory use.
  • The material maintains its structural integrity under relatively high levels of stress and load.
  • The material does not conduct heat well, and so provides a high level of insulation.
  • Polystyrene is one of the most recyclable of all plastics, reducing the carbon footprint of research.
  • Polystyrene offers better observability of results than polypropylene, thanks to its superior clarity.

Disadvantages

  • It does not have the same ability to withstand centrifugation as polypropylene. Many polystyrene tubes are only graded for half of the centrifugal RPM of polypropylene tubes.
  • It is not suitable for use with autoclaves.
  • It is not suitable for processes that involve freezing.
  • Its impact resistance is not as high as that of polypropylene.

Deciding Which Tube Is Suitable for Your Purposes

It is worth noting that both polypropylene and polystyrene tubes are commonly used in scientific and medical research, and meet both domestic and international regulation.

So, how do you make your choice? Well, while there are many similarities between the two materials, there are a few key areas in which the two types differ.

  • If you are going to be working with autoclaves, choose polypropylene tubes.
  • If you are going to be working with freezing temperatures, choose polypropylene tubes.
  • If you are going to be using a centrifuge set to above 1,500 rpm, choose polypropylene tubes.
  • If you are looking for a tube with a higher impact resistance, choose polypropylene tubes.
  • If you want a tube with exceptional clarity for better observation of results, choose polystyrene tubes.
  • If you are working with prolonged exposure to UV radiation, choose polystyrene tubes (although other materials may be more suitable for this application).

Note that our guide is designed to be just that — a guide. Remember to carefully research the materials and conduct due diligence before your experiment to achieve the most accurate results.

References

https://www.thomassci.com/scientific-supplies/Polystyrene-Tubes

https://omnexus.specialchem.com/selection-guide/high-impact-polystyrene

https://www.acmeplastics.com/content/the-applicational-benefits-of-polypropylene-plastic/