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Acetal (POM) and Aluminum Chloride: Chemical Resistance

Polyoxymethylene (acetal)

Rating

Concentration20 °C50 °CRemark
10 %CD
saturatedDD
solidDD

Material comparison at 20 °C

Aluminum Chloride: Material comparison at 20 °CAcetal (POM): C (highlighted); EPDM: A; FEP: A; Viton (FPM): A; HDPE: A; LDPE: A.EPDM: AFEP: AViton (FPM): AHDPE: ALDPE: ANBR: ANylon (PA): APolycarbonate: APMP: APP: APolystyrene: APTFE: APVC Rigid: APVDF: ASAN: AECTFE/ETFE: BPETG: BAcetal (POM): CPOMSS 316: CAluminium: DSS 304: DPolysulfone: –PVC Flexible: –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

The resistance of Acetal (POM) to Aluminum Chloride is concentration-dependent. Across the 3 tested concentrations (10 %, saturated, solid), the 20 °C rating ranges from C at lower concentrations to D at higher ones. This means engineers must verify which concentration their process actually involves before relying on a single rating. 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

Aluminum Chloride is commonly encountered in chemical processing and bleaching. Acetal (POM) (Polyoxymethylene (acetal)) is a thermoplastic typically used for tanks, piping, containers and liners. Because Aluminum Chloride is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.

Practical recommendation

Acetal (POM) has limited resistance to Aluminum Chloride 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, HDPE, LDPE, Nylon (PA) offer significantly better resistance and are rated A.

Did you know?

Polyoxymethylene (acetal) is commonly chosen for tanks, piping, containers and liners because of its combination of chemical resistance, mechanical strength, and cost-effectiveness.

Materials rated A or B at 20 °C

Based on the row for 10 %, 20 °C.

Thermoplastics
HDPE A, PP A, PVC Rigid A, LDPE A, Nylon (PA) A, Polycarbonate A, Polystyrene A, PETG B, PMP A, SAN A
Fluoropolymers
PTFE A, PVDF A, FEP A, ECTFE/ETFE B
Elastomers
EPDM A, Viton (FPM) A, NBR A

About Acetal (POM)

Acetal (POM) resists many organic solvents and fuels. Strong acids and oxidising agents degrade it.

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.