ChemicalResistance
ChemicalResistance.org

Sulfur Dioxide Chemical Resistance

Resistance ratings for 24 plastics, elastomers and metals at 20 °C and 50 °C. Listed at 2 concentrations, because the rating depends on it.

At a glance

Based on the row for moist, 20 °C.

Rated A, very good resistance
PTFE, HDPE, PP, PVDF, PVC Rigid, EPDM, SS 316, SS 304, LDPE, FEP, ECTFE/ETFE, PMP (12)
Rated B, good resistance
Polysulfone (1)
Rated C, limited resistance
Aluminium, Nylon (PA), Polycarbonate, Polystyrene (4)
Rated D, not resistant
Viton (FPM), NBR, Acetal (POM) (3)
No data in the source
Silicone, PVC Flexible, PETG, SAN
Rated lower at 50 °C than at 20 °C
PP (A → C), PVDF (A → D), PVC Rigid (A → B), Aluminium (C → D), Polystyrene (C → D)
Rating changes with concentration (20 °C)
HDPE: A (moist), C (liquid); PP: A (moist), D (liquid); PVDF: A (moist), D (liquid); PVC Rigid: A (moist), C (liquid); LDPE: A (moist), D (liquid); Polystyrene: C (moist), D (liquid); PMP: A (moist), D (liquid)

Based on the row for moist, 20 °C.

Rating profile by material family

Sulfur Dioxide: Rating profile by material familyThermoplastics: 5 A, 1 B, 3 C, 1 D, 3 no data. Fluoropolymers: 4 A. Elastomers: 1 A, 2 D, 1 no data. Metals: 2 A, 1 C.Thermoplastics (13)Thermoplastics: 5 × A, very good resistance (HDPE, LDPE, PP, PVC Rigid, PMP)A 5Thermoplastics: 1 × B, good resistance (Polysulfone)Thermoplastics: 3 × C, limited resistance (Polystyrene, Polycarbonate, Nylon (PA))C 3Thermoplastics: 1 × D, not resistant (Acetal (POM))Thermoplastics: 3 × no data (PVC Flexible, SAN, PETG)– 3Fluoropolymers (4)Fluoropolymers: 4 × A, very good resistance (PTFE, FEP, PVDF, ECTFE/ETFE)A 4Elastomers (4)Elastomers: 1 × A, very good resistance (EPDM)A 1Elastomers: 2 × D, not resistant (Viton (FPM), NBR)D 2Elastomers: 1 × no data (Silicone)– 1Metals (3)Metals: 2 × A, very good resistance (SS 316, SS 304)A 2Metals: 1 × C, limited resistance (Aluminium)C 1
A very good resistanceB good resistanceC limited resistanceD not resistantno data
Number of materials in each family with each rating at 20 °C.

Effect of temperature, 20 °C to 50 °C

Sulfur Dioxide: Effect of temperature, 20 °C to 50 °CPP A → C; PVC Rigid A → B; Polystyrene C → D; PVDF A → D; Aluminium C → D.ABCDPP: A at 20 °C, C at 50 °CPPPVC Rigid: A at 20 °C, B at 50 °CPVC RigidPolystyrene: C at 20 °C, D at 50 °CPolystyrenePVDF: A at 20 °C, D at 50 °CPVDFAluminium: C at 20 °C, D at 50 °CAluminium
20 °C50 °C
Materials whose rating differs between 20 °C and 50 °C. Materials not shown keep their rating or have no 50 °C value.

Substance

CAS number
7446-09-5
Formula
SO2
Hazard symbols in the source
T (toxic), C (corrosive) (pre-GHS European symbols; check the current safety data sheet)
Concentrations listed
moist; liquid
Name in the source (German)
Schwefeldioxid

Rating by concentration

Sulfur Dioxide: Rating by concentrationHDPE: moist A, liquid C→D. LDPE: moist A, liquid D. PP: moist A→C, liquid D. PVC Rigid: moist A→B, liquid C→D. PMP: moist A, liquid D. Polystyrene: moist C→D, liquid D. Polycarbonate: moist C*, liquid C→D. Acetal (POM): moist D, liquid D. Nylon (PA): moist C*, liquid C*. Polysulfone: moist B, liquid B. PTFE: moist A, liquid A. FEP: moist A, liquid A. PVDF: moist A→D, liquid D. ECTFE/ETFE: moist A, liquid A→B. EPDM: moist A, liquid A. Viton (FPM): moist D, liquid D. NBR: moist D, liquid D. SS 316: moist A, liquid A*. SS 304: moist A, liquid A*. Aluminium: moist C→D, liquid C*.moistliquidTHERMOPLASTICSHDPEHDPE, moist: A at 20 °C, A at 50 °CAHDPE, liquid: C at 20 °C, D at 50 °CC→DLDPELDPE, moist: A at 20 °C, A at 50 °CALDPE, liquid: D at 20 °C, D at 50 °CDPPPP, moist: A at 20 °C, C at 50 °CA→CPP, liquid: D at 20 °C, D at 50 °CDPVC RigidPVC Rigid, moist: A at 20 °C, B at 50 °CA→BPVC Rigid, liquid: C at 20 °C, D at 50 °CC→DPMPPMP, moist: A at 20 °C, A at 50 °CAPMP, liquid: D at 20 °C, D at 50 °CDPolystyrenePolystyrene, moist: C at 20 °C, D at 50 °CC→DPolystyrene, liquid: D at 20 °C, D at 50 °CDPolycarbonatePolycarbonate, moist: C at 20 °C (estimate)C*Polycarbonate, liquid: C at 20 °C, D at 50 °CC→DAcetal (POM)Acetal (POM), moist: D at 20 °C, D at 50 °CDAcetal (POM), liquid: D at 20 °C, D at 50 °CDNylon (PA)Nylon (PA), moist: C at 20 °C (estimate)C*Nylon (PA), liquid: C at 20 °C (estimate)C*PolysulfonePolysulfone, moist: B at 20 °C, B at 50 °CBPolysulfone, liquid: B at 20 °C, B at 50 °CBFLUOROPOLYMERSPTFEPTFE, moist: A at 20 °C, A at 50 °CAPTFE, liquid: A at 20 °C, A at 50 °CAFEPFEP, moist: A at 20 °C, A at 50 °CAFEP, liquid: A at 20 °C, A at 50 °CAPVDFPVDF, moist: A at 20 °C, D at 50 °CA→DPVDF, liquid: D at 20 °C, D at 50 °CDECTFE/ETFEECTFE/ETFE, moist: A at 20 °C, A at 50 °CAECTFE/ETFE, liquid: A at 20 °C, B at 50 °CA→BELASTOMERSEPDMEPDM, moist: A at 20 °CAEPDM, liquid: A at 20 °CAViton (FPM)Viton (FPM), moist: D at 20 °C, D at 50 °CDViton (FPM), liquid: D at 20 °C, D at 50 °CDNBRNBR, moist: D at 20 °C, D at 50 °CDNBR, liquid: D at 20 °C, D at 50 °CDMETALSSS 316SS 316, moist: A at 20 °C, A at 50 °CASS 316, liquid: A at 20 °C (estimate)A*SS 304SS 304, moist: A at 20 °C, A at 50 °CASS 304, liquid: A at 20 °C (estimate)A*AluminiumAluminium, moist: C at 20 °C, D at 50 °CC→DAluminium, liquid: C at 20 °C (estimate)C*
A very good resistanceB good resistanceC limited resistanceD not resistantno data
Each cell shows the rating at 20 °C. Where the rating at 50 °C differs, it follows the arrow. * marks an estimate in the source.
Show as a table
Materialmoistliquid
Thermoplastics
HDPEAC
LDPEAD
PPAD
PVC RigidAC
PVC Flexible––
PMPAD
PolystyreneCD
SAN––
PolycarbonateC*C
PETG––
Acetal (POM)DD
Nylon (PA)C*C*
PolysulfoneBB
Fluoropolymers
PTFEAA
FEPAA
PVDFAD
ECTFE/ETFEAA
Elastomers
EPDMAA
Viton (FPM)DD
NBRDD
Silicone––
Metals
SS 316AA*
SS 304AA*
AluminiumCC*

* estimated rating, given in the source without a temperature

Resistance table: Sulfur Dioxide, moist

Remark: mit H2O -> Schweflige Säure

Material20 °C50 °CRemark
Thermoplastics
HDPEAA
LDPEAA
PPAC
PVC RigidAB
PMPAA
PolystyreneCD
PolycarbonateC*–
Acetal (POM)DD
Nylon (PA)C*–
PolysulfoneBB
Fluoropolymers
PTFEAA
FEPAA
PVDFAD
ECTFE/ETFEAA
Elastomers
EPDMA–
Viton (FPM)DD
NBRDD
Metals
SS 316AA
SS 304AA
AluminiumCD

* estimated rating, given in the source without a temperature

Not rated in the source, so not in the table: PVC Flexible, SAN, PETG, Silicone

Resistance table: Sulfur Dioxide, liquid

Remark: mit H2O -> Schweflige Säure

Material20 °C50 °CRemark
Thermoplastics
HDPECD
LDPEDD
PPDD
PVC RigidCD
PMPDD
PolystyreneDD
PolycarbonateCD
Acetal (POM)DD
Nylon (PA)C*–
PolysulfoneBB
Fluoropolymers
PTFEAA
FEPAA
PVDFDD
ECTFE/ETFEAB
Elastomers
EPDMA–
Viton (FPM)DD
NBRDD
Metals
SS 316A*–
SS 304A*–
AluminiumC*–

* estimated rating, given in the source without a temperature

Not rated in the source, so not in the table: PVC Flexible, SAN, PETG, Silicone

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.

Frequently Asked Questions

Which materials resist Sulfur Dioxide at high concentrations?

The materials with an A rating (resistant) for Sulfur Dioxide at 20 °C are: PTFE, HDPE, PP, PVDF, PVC Rigid, EPDM, SS 316, SS 304. These can generally be used in direct contact.

Which materials should be avoided with Sulfur Dioxide?

Materials rated D (not resistant) for Sulfur Dioxide are: Viton (FPM), NBR, Acetal (POM). These should not be used in contact with Sulfur Dioxide.

Does temperature affect chemical resistance to Sulfur Dioxide?

Yes. 5 of 17 tested materials show a worse rating at 50 °C than at 20 °C for Sulfur Dioxide. Materials affected include: PP, PVDF, PVC Rigid, Aluminium, Polystyrene.

Is PTFE safe for Sulfur Dioxide?

PTFE is rated A for Sulfur Dioxide at 20 °C. A rating of A means resistant, B means limited resistance, C means partly resistant, and D means not resistant.

Does concentration affect chemical resistance to Sulfur Dioxide?

Yes. Sulfur Dioxide is tested at 2 concentrations (moist, liquid). Some materials change their rating depending on the concentration.

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.

Chemicals with a similar resistance profile

Same 20 °C rating on the share of materials shown.

Barium Hydroxide 76 %Phthalic Acid 76 %Formic Acid 75 %Zinc Chloride 74 %Zinc Sulfate 74 %Brake Fluid 72 %