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Nylon (PA) and Chromic Acid: Chemical Resistance

Polyamide (nylon)

Rating

Concentration20 °C50 °CRemark
10 %DD
20 %DD
50 %DD

Material comparison at 20 °C

Chromic Acid: Material comparison at 20 °CNylon (PA): D (highlighted); ECTFE/ETFE: A; FEP: A; Viton (FPM): A; PTFE: A; PVC Rigid: A.ECTFE/ETFE: AFEP: AViton (FPM): APTFE: APVC Rigid: APVC Flexible: APVDF: APMP: BSS 304: BSS 316: BAluminium: CHDPE: CLDPE: CPolycarbonate: CPP: CPolystyrene: CSAN: CEPDM: DNBR: DNylon (PA): DPAPETG: DAcetal (POM): DPolysulfone: DSilicone: –
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

Nylon (PA) maintains a consistent rating of D across all 3 tested concentrations (10 %, 20 %, 50 %) of Chromic Acid at 20 °C. The fact that the rating does not change with concentration within the tested range simplifies material selection, though the boundary conditions beyond this range remain untested. The rating remains stable between 20 °C and 50 °C, which means this material can also handle moderately elevated process temperatures without additional risk.

Application context

Chromic Acid is commonly encountered in surface cleaning and chemical processing. Nylon (PA) (Polyamide (nylon)) is a thermoplastic typically used for tanks, piping, containers and liners. Because Chromic Acid is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.

Practical recommendation

Nylon (PA) is not recommended for use with Chromic Acid. The D rating indicates that the material will suffer rapid and severe degradation, which may include cracking, dissolution, severe swelling, or complete structural failure. Using this combination risks equipment damage, leaks, and potential safety incidents. Consider using PVC Rigid, PVC Flexible, ECTFE/ETFE instead, which are rated A for this chemical and offer reliable long-term performance.

Did you know?

Chemical resistance testing according to DIN and ISO standards typically evaluates weight change, dimensional change, and retention of tensile strength after immersion.

Materials rated A or B at 20 °C

Based on the row for 50 %, 20 °C.

Thermoplastics
PVC Rigid A, PVC Flexible A, PMP B
Fluoropolymers
PTFE A, PVDF A, FEP A, ECTFE/ETFE A
Elastomers
Viton (FPM) A
Metals
SS 316 B, SS 304 B

About Nylon (PA)

Polyamide (nylon) resists fuels, oils and many solvents. Mineral acids, even dilute, and strong oxidisers attack it, and it absorbs water.

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.