Summary
- FEP is rated better with
- Esters and ethers (+100 points); Halogenated hydrocarbons (+85 points); Ketones and aldehydes (+79 points); Phenols (+75 points); Amines and nitrogen compounds (+44 points); Mineral acids (+39 points); Vegetable and animal oils, fats, essential oils (+32 points); Alcohols and glycols (+30 points); Oxidising agents and halogens (+27 points); Organic acids (+21 points); Fuels, mineral oils and aliphatic hydrocarbons (+21 points); Foods and beverages (+18 points)
- Within 10 points of each other
- Alkalis; Salts and salt solutions
Points are the difference in the share of rows rated A or B.
The two materials
SAN
Styrene-acrylonitrile
Styrene-acrylonitrile resists oils and dilute acids better than polystyrene, but ketones, esters and aromatic and chlorinated solvents still attack it.
Rated rows: 364. A 67 %, B 0 %, C 9 %, D 24 %
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 | SAN: rated A or B | FEP: rated A or B |
|---|---|---|
| Mineral acids | 61 % (18 rows) | 100 % (55 rows) |
| Organic acids | 79 % (24 rows) | 100 % (64 rows) |
| Alkalis | 100 % (8 rows) | 100 % (18 rows) |
| Salts and salt solutions | 100 % (80 rows) | 100 % (197 rows) |
| Oxidising agents and halogens | 73 % (26 rows) | 100 % (52 rows) |
| Alcohols and glycols | 70 % (33 rows) | 100 % (57 rows) |
| Phenols | 25 % (8 rows) | 100 % (14 rows) |
| Ketones and aldehydes | 21 % (19 rows) | 100 % (33 rows) |
| Esters and ethers | 0 % (19 rows) | 100 % (69 rows) |
| Amines and nitrogen compounds | 56 % (9 rows) | 100 % (38 rows) |
| Aromatic hydrocarbons | – | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 79 % (24 rows) | 100 % (74 rows) |
| Vegetable and animal oils, fats, essential oils | 68 % (22 rows) | 100 % (47 rows) |
| Halogenated hydrocarbons | 5 % (20 rows) | 90 % (49 rows) |
| Foods and beverages | 82 % (22 rows) | 100 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 110 in total, the first 40 shown.
| Chemical | Concentration | SAN | FEP |
|---|---|---|---|
| 1,2-Dichlorobenzene | D | A | |
| 1-Pentanethiol | D | A | |
| 5-Hydroxymethylfurfural | D | A | |
| Acetaldehyde | 40 % | D | A |
| Acetaldehyde | technical grade | D | A |
| Acetic Acid | 90 % | D | A |
| Acetone | D | A | |
| Allyl Alcohol | 96 % | D | A |
| Allyl Mustard Oil | D | A | |
| Amyl Acetate | D | A | |
| Amyl Cinnamaldehyde | D | A | |
| Anise Oil | D | A | |
| Benzyl Acetate | D | A | |
| Benzyl Alcohol | D | A | |
| Brake Fluid | D | A | |
| Bromine | D | A | |
| Bromochloromethane | 100 % | D | A |
| Butyl Acetate | 100 % | D | A |
| Butyl Acrylate | 100 % | D | A |
| Butyric Acid | D | A | |
| Carbazole | D | A | |
| Carbon Disulfide | D | A | |
| Carbon Tetrachloride | D | A | |
| Chlorine | 10 % wet | D | A |
| Chlorine | 97 % | D | A |
| Chlorine Gas | D | A | |
| Chlorobenzene | D | A | |
| Chloroethane (Ethyl Chloride) | D | A | |
| Chloroform | 100 % | D | A |
| Chloromethane (Methyl Chloride) | technical grade | D | A |
| Cinnamaldehyde | D | A | |
| Cloves | ground | D | A |
| Cyclohexanone | technical grade | D | A |
| DDT (Emulsion) | D | A | |
| Diacetone Alcohol | D | A | |
| Dibutyl Sebacate | technical grade | D | A |
| Dichloromethane | D | A | |
| Dichloropropane | 100 % | D | A |
| Diethyl Ether | technical grade | D | A |
| Diethyl Ketone | 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 SAN or FEP more chemical-resistant?
Of 355 chemicals rated for both materials at 20 °C, SAN and FEP share the same rating in 243 rows (68 %). SAN is rated better in 0 rows and FEP in 112 rows.
How do SAN and FEP compare for chemical resistance?
Based on 355 chemicals tested for both: SAN is rated better with –. FEP is rated better with Esters and ethers, Halogenated hydrocarbons, Ketones and aldehydes, Phenols. They perform similarly with Alkalis, Salts and salt solutions.
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.