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Acetal (POM) and Dichloromethane: Chemical Resistance

Polyoxymethylene (acetal)

Rating

Concentration20 °C50 °CRemark
concentration not statedC–

Material comparison at 20 °C

Dichloromethane: Material comparison at 20 °CAcetal (POM): C (highlighted); Aluminium: A; FEP: A; PTFE: A; PVDF: A; SS 304: A.Aluminium: AFEP: APTFE: APVDF: ASS 304: ASS 316: AECTFE/ETFE: BViton (FPM): CNylon (PA): CPMP: CAcetal (POM): CPOMPP: CEPDM: DHDPE: DLDPE: DNBR: DPolycarbonate: DPETG: DPolystyrene: DPolysulfone: DPVC Rigid: DPVC Flexible: DSAN: 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

Acetal (POM) has limited resistance (C) to Dichloromethane at 20 °C. This indicates that the chemical has a noticeable effect on the material, which may include visible swelling, softening, or a measurable loss of tensile strength. Use is generally limited to short-term or intermittent contact where full structural integrity is not required. 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

Dichloromethane is commonly encountered in coatings and paints and cleaning and degreasing. 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 Dichloromethane 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, FEP, PTFE, PVDF offer significantly better resistance and are rated A.

Did you know?

In industrial practice, Acetal (POM) components exposed to Dichloromethane 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

Fluoropolymers
PTFE A, PVDF A, FEP A, ECTFE/ETFE B
Metals
SS 316 A, SS 304 A, Aluminium 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.