The Safety of sodium polyacrylate for human & environmental impact

What’s sodium polyacrylate?

Sodium polyacrylate is a white granular or powder polymer which looks like sugar.

Sodium Polyacrylate

As a kind of super absorbent polymer (SAP), it has strong absorbency for hundreds times its own weight in water.
After absorbing water, it turns to water gel form which locks water firmly.

Information Form

Chemical formula  (C3H3NaO2)n
Density 1.22 g/cm3
CAS Number 9003-04-7
ECHA InfoCard 100.118.171

The safety of sodium polyacrylate

For human

As we know, it is the main absorbent material in baby paper diapers.
Now we’ll talk about the safety when it touching our skin.

Acrylic acid

Acrylic acid may be the only substance in sodium polyacrylate which can irritate and hurt the skin.
Sodium polyacrylate is consists of acrylic acid and sodium hydroxide. As this is not a complete reaction, there would be few acrylics acid left.

The key is how much is the acrylic acid left.

As a leftover from the manufacturing process, the acrylic acid value should be less than 300 PPM for safe, especially for paper diaper, nursing pad, sanitary towel, etc.
For your reference, here’s a material safety data sheets (documents created by SGS), sodium polyacrylate is totally safe.

Other safety factors

As a Super absorbent material, it can also cause certain dangers if not handled properly.

  • It may irritate the lungs when you inhale tiny sodium polyacrylate powder;
  • It can expand quickly when meeting water. So, please do not eat it;
  • After absorbing, it turns to water gel form – which is slippery and will cause serious clogging.

Conclusion

Sodium polyacrylate is safe for human. It’s non-toxic and free from any major safety risks.

For environment 

As we know, potassium polyacrylate, another kind of super absorbent polymers, can be used as the water retaining agent for plants.
And it can be broken into urea, carbon dioxide, water, and potassium.

So, what about sodium polyacrylate?

Decomposition product in soil

Sodium polyacrylate can be broken into urea, carbon dioxide, water, and sodium.

And the problem is sodium.

In general, small amounts of sodium won’t affect the soil and harm to the natural environment.
But that’s different when we frequently put plenty them into the soil – which would cause salty groundwater to rise towards the surface and contaminate soils.

No working at all

Actually, sodium polyacrylate can’t keep retaining water at all. There’re too many differences between it and potassium polyacrylate in the soil.

It:

  • can only absorb a few of water in the soil because of the metallic ion concentration of soil extract;
  • would melt in one month after absorbing water becoming gel form.

Conclusion

It’s unwise to use Sodium polyacrylate as water retaining agent. It’s no working and would cause salinization of soil.

2018-10-07T22:20:36+00:00Super Absorbent Polymer|

About the Author:

A Supplier Of Super Absorbent Polymer (Potassium Polyacrylate & Sodium Polyacrylate). It's easy to learn and purchase super absorbent polymer on our website: www.socochem.com