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PP and Aqua Regia: Chemical Resistance

Polypropylene

Rating

Concentration20 °C50 °CRemark
concentration not statedDD

Material comparison at 20 °C

Aqua Regia: Material comparison at 20 °CPP: D (highlighted); ECTFE/ETFE: A; PTFE: A; FEP: B; PMP: C; PVDF: C.ECTFE/ETFE: APTFE: AFEP: BPMP: CPVDF: CSAN: CAluminium: DEPDM: DViton (FPM): DHDPE: DLDPE: DNBR: DNylon (PA): DPolycarbonate: DPETG: DAcetal (POM): DPP: DPPPolystyrene: DPolysulfone: DPVC Rigid: DPVC Flexible: DSS 304: DSS 316: 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

PP is not resistant (D) to Aqua Regia and should not be used in direct contact. The chemical is expected to cause rapid degradation, which can include dissolution, cracking, severe swelling, or complete structural failure of the material.

Application context

Aqua Regia is commonly encountered in metal finishing and chemical processing. PP (Polypropylene) is a thermoplastic typically used for tanks, piping, containers and liners. Because Aqua Regia is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.

Practical recommendation

PP is not recommended for use with Aqua Regia. 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 ECTFE/ETFE, PTFE instead, which are rated A for this chemical and offer reliable long-term performance.

Did you know?

The chemical resistance of PP depends not only on the chemical concentration but also on exposure time, mechanical stress, and the presence of other chemicals in the mixture.

Materials rated A or B at 20 °C

Fluoropolymers
PTFE A, FEP B, ECTFE/ETFE A

About PP

Polypropylene resists most acids, alkalis and salt solutions. Concentrated oxidising acids, chlorinated solvents and aromatic hydrocarbons attack it, and it turns brittle below about 0 °C.

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.