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Viton (FPM) and Phthalic Acid: Chemical Resistance

Fluoroelastomer (FKM/FPM)

Rating

Concentration20 °C50 °CRemark
saturatedBC

Material comparison at 20 °C

Phthalic Acid: Material comparison at 20 °CViton (FPM): B (highlighted); Aluminium: A; EPDM: A; FEP: A; HDPE: A; LDPE: A.Aluminium: AEPDM: AFEP: AHDPE: ALDPE: APETG: AAcetal (POM): APP: APolystyrene: APTFE: APVC Rigid: APVDF: ASAN: ASS 304: ASS 316: AViton (FPM): BFPMNylon (PA): CPolycarbonate: CNBR: DECTFE/ETFE: –PMP: –Polysulfone: –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

Viton (FPM) shows good but limited resistance (B) to Phthalic Acid at saturated at 20 °C. The material can be used in contact with this chemical, but minor effects such as slight swelling or a small reduction in mechanical properties may occur over extended exposure periods. Regular inspection of components in service is advisable. 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

Phthalic Acid is commonly encountered in chemical processing and water treatment. Viton (FPM) (Fluoroelastomer (FKM/FPM)) is an elastomer typically used for seals, O-rings, hoses and flexible connections. The compatibility between these two is therefore an important consideration for engineers and procurement teams selecting containment, transfer, or processing equipment.

Practical recommendation

Viton (FPM) is suitable for use with Phthalic Acid under normal conditions, but some minor effects on the material are expected over time. Periodic monitoring for swelling, softening, or weight change is recommended, especially for long-service components. Avoid prolonged exposure at elevated temperatures, as the resistance decreases further at 50 °C. For safety-critical or long-life applications, consider HDPE, LDPE, PETG instead, which are rated A for this chemical.

Did you know?

Fluoroelastomer (FKM/FPM) is commonly chosen for seals, O-rings, hoses and flexible connections 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 saturated, 20 °C.

Thermoplastics
HDPE A, PP A, PVC Rigid A, LDPE A, Acetal (POM) A, Polystyrene A, PETG A, SAN A
Fluoropolymers
PTFE A, PVDF A, FEP A
Elastomers
EPDM A
Metals
SS 316 A, SS 304 A, Aluminium A

About Viton (FPM)

Fluoroelastomer (Viton, FKM/FPM) resists fuels, oils and many acids. Ketones, esters, amines and hot water or steam attack 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.