Summary
- FEP is rated better with
- Mineral acids (+95 points); Phenols (+92 points); Organic acids (+75 points); Oxidising agents and halogens (+74 points); Amines and nitrogen compounds (+50 points); Ketones and aldehydes (+47 points); Alcohols and glycols (+33 points); Halogenated hydrocarbons (+27 points); Salts and salt solutions (+22 points); Esters and ethers (+20 points)
- Within 10 points of each other
- Alkalis; Aromatic hydrocarbons; Fuels, mineral oils and aliphatic hydrocarbons; Vegetable and animal oils, fats, essential oils; Foods and beverages
Points are the difference in the share of rows rated A or B.
The two materials
Nylon (PA)
Polyamide (nylon)
Polyamide (nylon) resists fuels, oils and many solvents. Mineral acids, even dilute, and strong oxidisers attack it, and it absorbs water.
Rated rows: 945. A 44 %, B 21 %, C 17 %, D 18 %
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 %
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 | Nylon (PA): rated A or B | FEP: rated A or B |
|---|---|---|
| Mineral acids | 5 % (63 rows) | 100 % (55 rows) |
| Organic acids | 25 % (63 rows) | 100 % (64 rows) |
| Alkalis | 91 % (22 rows) | 100 % (18 rows) |
| Salts and salt solutions | 78 % (194 rows) | 100 % (197 rows) |
| Oxidising agents and halogens | 26 % (62 rows) | 100 % (52 rows) |
| Alcohols and glycols | 67 % (58 rows) | 100 % (57 rows) |
| Phenols | 8 % (13 rows) | 100 % (14 rows) |
| Ketones and aldehydes | 53 % (32 rows) | 100 % (33 rows) |
| Esters and ethers | 80 % (65 rows) | 100 % (69 rows) |
| Amines and nitrogen compounds | 50 % (34 rows) | 100 % (38 rows) |
| Aromatic hydrocarbons | 100 % (14 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 97 % (73 rows) | 100 % (74 rows) |
| Vegetable and animal oils, fats, essential oils | 98 % (46 rows) | 100 % (47 rows) |
| Halogenated hydrocarbons | 63 % (70 rows) | 90 % (49 rows) |
| Foods and beverages | 98 % (46 rows) | 100 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 303 in total, the first 40 shown.
| Chemical | Concentration | Nylon (PA) | FEP |
|---|---|---|---|
| Acetic Acid | 10 % | D | A |
| Acetic Acid | 100 % | D | A |
| Acetic Acid | 5 % | D | A |
| Acetic Acid | 50 % | D | A |
| Acetic Acid | 90 % | D | A |
| Acetyl Chloride | 100 % | D | A |
| Allyl Acetate | 100 % | D | A |
| Ammonium Persulfate | saturated | D | A |
| Ammonium Persulfate | aqueous | D | A |
| Antimony Trichloride | 90 % | D | A |
| Antimony Trichloride | aqueous | D | A |
| Battery Acid | 38 % | D | A |
| Benzenesulfonic Acid | saturated | D | A |
| Benzyl Alcohol | D | A | |
| Bromine | D | A | |
| Bromine Vapors | D | A | |
| Bromochloromethane | 100 % | D | A |
| Bromoform | D | A | |
| Calcium Chloride | alcoholic solution | D | A |
| Calcium Hypochlorite | D | A | |
| Calcium Hypochlorite | aqueous | D | A |
| Calcium Hypochlorite | aqueous | D | A |
| Carbon Tetrachloride | D | A | |
| Cetyl Alcohol | 100 % | D | A |
| Chloral Hydrate | technical grade | D | A |
| Chloramine-T | dilute | D | A |
| Chlorine | 10 % wet | D | A |
| Chlorine | 97 % | D | A |
| Chlorine Gas | D | A | |
| Chlorine Water | D | A | |
| Chloroacetic Acid | D | A | |
| Chloroacetic Acid | 50 % | D | A |
| Chlorobenzene | D | A | |
| Chloroethanol | technical grade | D | A |
| Chloromethane (Methyl Chloride) | technical grade | D | A |
| Chromic Acid | 10 % | D | A |
| Chromic Acid | 20 % | D | A |
| Chromic Acid | 50 % | D | A |
| Cresol | D | A | |
| Dichloroacetic Acid | 50 % | D | A |
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 Nylon (PA) or FEP more chemical-resistant?
Of 879 chemicals rated for both materials at 20 °C, Nylon (PA) and FEP share the same rating in 377 rows (43 %). Nylon (PA) is rated better in 6 rows and FEP in 496 rows.
How do Nylon (PA) and FEP compare for chemical resistance?
Based on 879 chemicals tested for both: Nylon (PA) is rated better with –. FEP is rated better with Mineral acids, Phenols, Organic acids, Oxidising agents and halogens. They perform similarly with Alkalis, Aromatic hydrocarbons, Fuels, mineral oils and aliphatic hydrocarbons, Vegetable and animal oils, fats, essential oils.
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.