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NBR and Phthalic Acid: Chemical Resistance

Nitrile butadiene rubber

Rating

Concentration20 °C50 °CRemark
saturatedDD

Material comparison at 20 °C

Phthalic Acid: Material comparison at 20 °CNBR: D (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): BNylon (PA): CPolycarbonate: CNBR: DNBRECTFE/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

NBR is not resistant (D) to Phthalic Acid at saturated and should not be used in direct contact. The chemical is expected to cause rapid degradation, which can include dissolution, cracking, severe swelling, or complete structural failure of the material.

Application context

Phthalic Acid is commonly encountered in metal finishing and surface cleaning. NBR (Nitrile butadiene rubber) 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

NBR is not recommended for use with Phthalic Acid. The D rating indicates that the material will suffer rapid and severe degradation, which may include cracking, dissolution, severe swelling, or complete structural failure. Using this combination risks equipment damage, leaks, and potential safety incidents. Consider using HDPE, LDPE, PETG instead, which are rated A for this chemical and offer reliable long-term performance.

Did you know?

In industrial practice, NBR components exposed to Phthalic Acid 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

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, Viton (FPM) B
Metals
SS 316 A, SS 304 A, Aluminium A

About NBR

Nitrile rubber resists mineral oils and fuels. Ketones, esters, chlorinated solvents, strong oxidisers and ozone 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.