Summary
- FEP is rated better with
- Phenols (+100 points); Esters and ethers (+99 points); Aromatic hydrocarbons (+93 points); Ketones and aldehydes (+91 points); Mineral acids (+87 points); Amines and nitrogen compounds (+87 points); Oxidising agents and halogens (+85 points); Halogenated hydrocarbons (+70 points); Organic acids (+63 points); Alcohols and glycols (+55 points); Fuels, mineral oils and aliphatic hydrocarbons (+41 points); Alkalis (+36 points); Vegetable and animal oils, fats, essential oils (+31 points); Salts and salt solutions (+18 points)
- Within 10 points of each other
- 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 %
NBR
Nitrile butadiene rubber
Nitrile rubber resists mineral oils and fuels. Ketones, esters, chlorinated solvents, strong oxidisers and ozone attack it.
Rated rows: 983. A 36 %, B 9 %, C 19 %, D 36 %
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 | NBR: rated A or B |
|---|---|---|
| Mineral acids | 100 % (55 rows) | 13 % (63 rows) |
| Organic acids | 100 % (64 rows) | 37 % (63 rows) |
| Alkalis | 100 % (18 rows) | 64 % (22 rows) |
| Salts and salt solutions | 100 % (197 rows) | 82 % (198 rows) |
| Oxidising agents and halogens | 100 % (52 rows) | 15 % (62 rows) |
| Alcohols and glycols | 100 % (57 rows) | 45 % (58 rows) |
| Phenols | 100 % (14 rows) | 0 % (14 rows) |
| Ketones and aldehydes | 100 % (33 rows) | 9 % (35 rows) |
| Esters and ethers | 100 % (69 rows) | 1 % (76 rows) |
| Amines and nitrogen compounds | 100 % (38 rows) | 13 % (39 rows) |
| Aromatic hydrocarbons | 100 % (14 rows) | 7 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 100 % (74 rows) | 59 % (78 rows) |
| Vegetable and animal oils, fats, essential oils | 100 % (47 rows) | 69 % (48 rows) |
| Halogenated hydrocarbons | 90 % (49 rows) | 20 % (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: 482 in total, the first 40 shown.
| Chemical | Concentration | FEP | NBR |
|---|---|---|---|
| 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-Pentanethiol | A | D | |
| 5-Hydroxymethylfurfural | A | D | |
| Acetaldehyde | 40 % | A | D |
| Acetaldehyde | technical grade | A | D |
| Acetic Acid | 100 % | A | D |
| Acetic Acid | 50 % | A | D |
| Acetic Acid | 90 % | A | D |
| Acetic Anhydride | technical grade | A | D |
| Acetone | A | D | |
| Acetonitrile | A | D | |
| Acetyl Chloride | 100 % | A | D |
| Acrylonitrile | A | D | |
| Allyl Acetate | 100 % | A | D |
| Allyl Chloride | 100 % | A | D |
| Allyl Mustard Oil | A | D | |
| Ammonium Carbonate | 50 % | A | D |
| Ammonium Carbonate | aqueous | A | D |
| Ammonium Hydroxide (Ammonia Solution) | A | D | |
| Ammonium Persulfate | saturated | A | D |
| Ammonium Persulfate | aqueous | A | D |
| Amyl Acetate | A | D | |
| Amyl Chloride | A | D | |
| Amyl Cinnamaldehyde | A | D | |
| Amyl Phthalate | 100 % | A | D |
| Aniline | A | D | |
| Anise Oil | A | D | |
| Anisole | 100 % | A | D |
| Battery Acid | 38 % | A | D |
| Benzaldehyde | A | D | |
| Benzene | A | D | |
| Benzenesulfonic Acid | saturated | A | D |
| Benzyl Acetate | A | D | |
| Benzyl Alcohol | A | D | |
| Benzyl Chloride | 100 % | A | D |
| Bisulfite Liquor with SO2 | 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 NBR more chemical-resistant?
Of 905 chemicals rated for both materials at 20 °C, FEP and NBR share the same rating in 332 rows (37 %). FEP is rated better in 572 rows and NBR in 1 rows.
How do FEP and NBR compare for chemical resistance?
Based on 905 chemicals tested for both: FEP is rated better with Phenols, Esters and ethers, Aromatic hydrocarbons, Ketones and aldehydes. NBR is rated better with –. They perform similarly with 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.