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FEP and Dichlorodifluoromethane (R-12): Chemical Resistance

Fluorinated ethylene propylene

Rating

Concentration20 °C50 °CRemark
technical gradeCC
concentration not statedCC

Material comparison at 20 °C

Dichlorodifluoromethane (R-12): Material comparison at 20 °CFEP: C (highlighted); Nylon (PA): A; Acetal (POM): A; Polysulfone: A; PTFE: A; PVC Rigid: B.Nylon (PA): AAcetal (POM): APolysulfone: APTFE: APVC Rigid: BAluminium: CEPDM: CFEP: CFEPViton (FPM): CLDPE: CNBR: CPVDF: CSAN: CHDPE: DPolycarbonate: DPP: DPolystyrene: DPVC Flexible: DECTFE/ETFE: –PETG: –PMP: –Silicone: –SS 304: –SS 316: –
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

FEP maintains a consistent rating of C across all 2 tested concentrations (technical grade) of Dichlorodifluoromethane (R-12) 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

Dichlorodifluoromethane (R-12) is commonly encountered in bleaching and chemical processing. FEP (Fluorinated ethylene propylene) is a fluoropolymer typically used for seals, gaskets, valve seats and lined equipment. The compatibility between these two is therefore an important consideration for engineers and procurement teams selecting containment, transfer, or processing equipment.

Practical recommendation

FEP has limited resistance to Dichlorodifluoromethane (R-12) 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, Nylon (PA), Acetal (POM), Polysulfone offer significantly better resistance and are rated A.

Did you know?

Fluorinated ethylene propylene was first developed in the 1960s and remains one of the most widely used fluoropolymers in chemical handling equipment.

Materials rated A or B at 20 °C

Based on the row for technical grade, 20 °C.

Thermoplastics
PVC Rigid B, Nylon (PA) A, Acetal (POM) A, Polysulfone A
Fluoropolymers
PTFE A

About FEP

FEP has nearly the chemical resistance of PTFE and can be melt-processed. Its service temperature, about 200 °C, is lower than that of PTFE.

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.