CAUSTIC SODA (80%) & Polypropylene Compatibility

Caustic Soda (80%) is very concentrated sodium hydroxide (NaOH, CAS 1310-73-2). At this strength caustic is solid at room temperature, so it is handled hot or molten, or as flake and bead caustic that is dissolved on site. It is used where water must be kept to a minimum, such as in specialty chemical synthesis and in making high-strength cleaners. Because it is stored at elevated temperatures, check each tank resin's temperature limit. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Caustic Soda Solution Safety Data Sheet (SDS) – Formosa Plastics USA

Not recommended in PVDF. Arkema, the maker of Kynar®, does not recommend Kynar Flex® 2850 PVDF, the resin we mold, for long-term service with Sodium Hydroxide (Greater than 50% in water). Ask us about HDPE or polypropylene for this chemical. Arkema’s limits are for solid resin at atmospheric pressure and do not account for mixtures. Source: Arkema Kynar® PVDF chemical resistance chart. Confirm your application with Bailiff before ordering.

At a glance

Polypropylene is the recommended tank material for Caustic Soda (80%), rated Excellent. Avoid PVDF (Kynar®) tanks; PVDF fittings; Buna-N and Viton® gaskets; titanium hardware. Rated Fair (contact us before use): HDPE and nylon tanks; HDPE fittings.

  • Excellent No or minor effect. Recommended.
  • Good Slight effect. Generally suitable.
  • Fair Moderate effect. Limited or conditional use — contact us.
  • Not Recommended Severe effect. Do not use.
  • No Data Not tested. Contact us before use.

Tank Resins

How Caustic Soda (80%) works with the plastics used to make our storage tanks.

Material Relative cost Rating
HDPE $ Fair
Polypropylene $$ Excellent
Nylon $$$ Fair
PVDF (Kynar®) $$$$ Not Recommended

Fittings

How Caustic Soda (80%) works with the plastics used for tank fittings.

Material Rating
HDPE Fair
PVC Excellent
CPVC Excellent
Polypropylene Excellent
PVDF Not Recommended

Gaskets & O-Rings

How Caustic Soda (80%) works with gasket and O-ring materials.

Material Rating
Buna-N Not Recommended
EPDM Good
Viton® Not Recommended

Metals

How Caustic Soda (80%) works with the metals used for fittings and bolts.

Material Rating
316 Stainless Steel Good
Hastelloy Excellent
Titanium Not Recommended
Aluminum No Data

Request a Polypropylene Tank Quote

Storing this chemical in polypropylene?

Tanks & Fittings Built for It

Polypropylene tanks from 25 to 6,000 gallons with polypropylene fittings installed. Confirm concentration and temperature with us before you order.

Tell Us What You’re Storing

Send the chemical, concentration, temperature and size. We’ll match the tank and fittings and send a quote.