ChemicalResistance
ChemicalResistance.org

PVC Flexible and Sodium Hydroxide (Caustic Soda): Chemical Resistance

Flexible (plasticised) polyvinyl chloride

Rating

Concentration20 °C50 °CRemark
1 %––
30 %AC
45 %AC
50 %––
60 %––
concentrated––

Material comparison at 20 °C

Sodium Hydroxide (Caustic Soda): Material comparison at 20 °CPVC Flexible: – (highlighted); EPDM: A; HDPE: A; LDPE: A; Nylon (PA): A; PMP: A.EPDM: AHDPE: ALDPE: ANylon (PA): APMP: APP: APolystyrene: APolysulfone: APTFE: ASS 304: ASS 316: ANBR: BViton (FPM): CAcetal (POM): CAluminium: DPolycarbonate: DPETG: DPVDF: DECTFE/ETFE: –FEP: –PVC Rigid: –PVC Flexible: –PVC-PSAN: –Silicone: –
A very good resistanceB good resistanceC limited resistanceD not resistantno data
Each bar is one material. Taller bars indicate better resistance. The highlighted bar is the current material.

Resistance overview

PVC Flexible shows excellent resistance to Sodium Hydroxide (Caustic Soda) across all 2 tested concentrations (30 %, 45 %) at 20 °C, making it a reliable choice for storage, transfer, and handling applications involving this chemical at any of the tested strengths. However, at 50 °C the resistance rating drops, indicating that temperature must be factored into the design. For heated applications, additional testing under actual service conditions is strongly recommended.

Application context

Sodium Hydroxide (Caustic Soda) is commonly encountered in pulp and paper and textile processing. PVC Flexible (Flexible (plasticised) polyvinyl chloride) is a thermoplastic typically used for tanks, piping, containers and liners. Because Sodium Hydroxide (Caustic Soda) is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.

Practical recommendation

No resistance data is available for PVC Flexible in contact with Sodium Hydroxide (Caustic Soda). Before using this combination, consult the material manufacturer or conduct independent testing.

Did you know?

Flexible (plasticised) polyvinyl chloride was first developed in the 1920s and remains one of the most widely used thermoplastics in chemical handling equipment.

Materials rated A or B at 20 °C

Based on the row for 60 %, 20 °C.

Thermoplastics
HDPE A, PP A, LDPE A, Nylon (PA) A, Polystyrene A, Polysulfone A, PMP A
Fluoropolymers
PTFE A
Elastomers
EPDM A, NBR B
Metals
SS 316 A, SS 304 A

About PVC Flexible

Flexible PVC shares the solvent weaknesses of rigid PVC, and any liquid that extracts the plasticiser also hardens it. It is generally less resistant than rigid PVC.

Rating scale

A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.

About this data

The ratings come from the chemical resistance list published by Bürkle GmbH, which compiled them from raw-material manufacturers’ data. They describe laboratory tests on the raw material at 20 °C and 50 °C.

A finished part also sees pressure, mechanical stress, welds and mixtures that a laboratory test does not. Treat the rating as a first filter and test under your own conditions before relying on it.