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Polystyrene and Chromic Acid: Chemical Resistance

Polystyrene

Rating

Concentration20 °C50 °CRemark
10 %AA
20 %A–
50 %CC

Material comparison at 20 °C

Chromic Acid: Material comparison at 20 °CPolystyrene: C (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: CPSSAN: CEPDM: DNBR: DNylon (PA): DPETG: 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

The resistance of Polystyrene to Chromic Acid is concentration-dependent. Across the 3 tested concentrations (10 %, 20 %, 50 %), the 20 °C rating ranges from A at lower concentrations to C at higher ones. This means engineers must verify which concentration their process actually involves before relying on a single rating. 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. Polystyrene (Polystyrene) 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

Polystyrene has limited resistance to Chromic Acid and should only be used for short-term or intermittent contact at ambient temperature. The C rating means the material undergoes noticeable changes — swelling, loss of strength, or surface degradation — that make it unsuitable for permanent installations. For prolonged or continuous exposure, PVC Rigid, PVC Flexible, ECTFE/ETFE offer significantly better resistance and are rated A.

Did you know?

In industrial practice, Polystyrene components exposed to Chromic Acid are typically inspected for swelling, discoloration, or loss of mechanical strength as early indicators of chemical attack.

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 Polystyrene

Polystyrene is attacked by most organic solvents, including ketones, esters, aromatic and chlorinated hydrocarbons. It is used for dilute aqueous solutions.

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.