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Acetal (POM) and Calcium Chloride: Chemical Resistance

Polyoxymethylene (acetal)

Rating

Concentration20 °C50 °CRemark
aqueousC*–
alcoholic solutionC*–

* estimated rating, given in the source without a temperature

Material comparison at 20 °C

Calcium Chloride: Material comparison at 20 °CAcetal (POM): C (highlighted); ECTFE/ETFE: A; EPDM: A; FEP: A; Viton (FPM): A; HDPE: A.ECTFE/ETFE: AEPDM: AFEP: AViton (FPM): AHDPE: ALDPE: ANBR: ANylon (PA): APolycarbonate: APETG: APMP: APP: APolystyrene: APolysulfone: APTFE: APVC Rigid: APVC Flexible: APVDF: ASAN: ASS 304: ASS 316: AAluminium: CAcetal (POM): CPOMSilicone: –
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

Acetal (POM) maintains a consistent rating of C across all 2 tested concentrations (aqueous, alcoholic solution) of Calcium Chloride 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

Calcium Chloride is commonly encountered in bleaching and waste treatment. Acetal (POM) (Polyoxymethylene (acetal)) is a thermoplastic typically used for tanks, piping, containers and liners. The compatibility between these two is therefore an important consideration for engineers and procurement teams selecting containment, transfer, or processing equipment.

Practical recommendation

Acetal (POM) has limited resistance to Calcium 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 aqueous, 20 °C.

Thermoplastics
HDPE A, PP A, PVC Rigid A, LDPE A, Nylon (PA) A, Polycarbonate A, PVC Flexible A, Polystyrene A, Polysulfone A, PETG A, PMP A, SAN A
Fluoropolymers
PTFE A, PVDF A, FEP A, ECTFE/ETFE A
Elastomers
EPDM A, Viton (FPM) A, NBR A
Metals
SS 316 A, SS 304 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.