Summary
- FEP is rated better with
- Aromatic hydrocarbons (+100 points); Fuels, mineral oils and aliphatic hydrocarbons (+99 points); Vegetable and animal oils, fats, essential oils (+96 points); Phenols (+93 points); Esters and ethers (+75 points); Ketones and aldehydes (+69 points); Halogenated hydrocarbons (+67 points); Amines and nitrogen compounds (+67 points); Mineral acids (+60 points); Organic acids (+53 points); Alcohols and glycols (+47 points); Oxidising agents and halogens (+35 points)
- Within 10 points of each other
- Alkalis; Salts and salt solutions; Foods and beverages
Points are the difference in the share of rows rated A or B.
The two materials
FEP
Fluorinated ethylene propylene
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.
Rated rows: 908. A 99 %, B 0 %, C 1 %, D 0 %
EPDM
Ethylene propylene diene rubber
EPDM resists water, steam, alkalis, ketones and alcohols. Mineral oils, fuels and aromatic solvents swell it severely.
Rated rows: 976. A 44 %, B 9 %, C 20 %, D 28 %
Share of rows rated A or B, by chemical class
How often the two ratings agree
Chemical classes were assigned by this site, not by the source. Mixtures and trade products without a clear class are not counted.
By chemical class
| Chemical class | FEP: rated A or B | EPDM: rated A or B |
|---|---|---|
| Mineral acids | 100 % (55 rows) | 40 % (63 rows) |
| Organic acids | 100 % (64 rows) | 47 % (64 rows) |
| Alkalis | 100 % (18 rows) | 100 % (22 rows) |
| Salts and salt solutions | 100 % (197 rows) | 98 % (198 rows) |
| Oxidising agents and halogens | 100 % (52 rows) | 65 % (62 rows) |
| Alcohols and glycols | 100 % (57 rows) | 53 % (58 rows) |
| Phenols | 100 % (14 rows) | 7 % (14 rows) |
| Ketones and aldehydes | 100 % (33 rows) | 31 % (35 rows) |
| Esters and ethers | 100 % (69 rows) | 25 % (72 rows) |
| Amines and nitrogen compounds | 100 % (38 rows) | 33 % (39 rows) |
| Aromatic hydrocarbons | 100 % (14 rows) | 0 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 100 % (74 rows) | 1 % (78 rows) |
| Vegetable and animal oils, fats, essential oils | 100 % (47 rows) | 4 % (48 rows) |
| Halogenated hydrocarbons | 90 % (49 rows) | 23 % (71 rows) |
| Foods and beverages | 100 % (46 rows) | 93 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 427 in total, the first 40 shown.
| Chemical | Concentration | FEP | EPDM |
|---|---|---|---|
| 1,2-Dibromoethane | A | D | |
| 1,2-Dichlorobenzene | A | D | |
| 1,3-Butadiene | A | D | |
| 1,4-Dichlorobenzene | A | D | |
| 1-Chloronaphthalene | A | D | |
| 1-Heptanol | A | D | |
| 1-Pentanethiol | A | D | |
| Acetic Acid | 100 % | A | D |
| Acetic Acid | 50 % | A | D |
| Acetic Acid | 90 % | A | D |
| Acetyl Chloride | 100 % | A | D |
| Acrylonitrile | A | D | |
| Allyl Chloride | 100 % | A | D |
| Almond Oil | A | D | |
| Amyl Chloride | A | D | |
| Amyl Cinnamaldehyde | A | D | |
| Aniline | A | D | |
| Anise Oil | A | D | |
| Anisole | 100 % | A | D |
| Beef Tallow | A | D | |
| Beef Tallow Emulsion | sulfuriert | A | D |
| Benzene | A | D | |
| Benzenesulfonic Acid | saturated | A | D |
| Benzyl Chloride | 100 % | A | D |
| Bitter Orange Oil | A | D | |
| Bitumen | A | D | |
| Bone Oil | A | D | |
| Bromine | A | D | |
| Bromine Vapors | A | D | |
| Bromobenzene | A | D | |
| Bromochloromethane | 100 % | A | D |
| Bromoform | A | D | |
| Bromomethane | technical grade | A | D |
| Butane | technical grade | A | D |
| Butyl Acrylate | 100 % | A | D |
| Butyl Stearate | 100 % | A | D |
| Butylamine | A | D | |
| Butylphenol | 100 % | A | D |
| Butyric Acid | A | D | |
| Calcium Bisulfite | saturated | A | D |
Rating scale
- A very good resistance
- B good resistance
- C limited resistance
- D not resistant
- – no data
- K no general statement possible
A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.
More comparisons
Frequently Asked Questions
Is FEP or EPDM more chemical-resistant?
Of 905 chemicals rated for both materials at 20 °C, FEP and EPDM share the same rating in 395 rows (44 %). FEP is rated better in 508 rows and EPDM in 2 rows.
How do FEP and EPDM compare for chemical resistance?
Based on 905 chemicals tested for both: FEP is rated better with Aromatic hydrocarbons, Fuels, mineral oils and aliphatic hydrocarbons, Vegetable and animal oils, fats, essential oils, Phenols. EPDM is rated better with –. They perform similarly with Alkalis, Salts and salt solutions, Foods and beverages.
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.