Summary
- FEP is rated better with
- Halogenated hydrocarbons (+86 points); Aromatic hydrocarbons (+86 points); Fuels, mineral oils and aliphatic hydrocarbons (+37 points); Esters and ethers (+37 points); Ketones and aldehydes (+31 points); Mineral acids (+30 points); Oxidising agents and halogens (+28 points); Vegetable and animal oils, fats, essential oils (+25 points); Phenols (+21 points); Amines and nitrogen compounds (+21 points)
- Within 10 points of each other
- Organic acids; Alkalis; Salts and salt solutions; Alcohols and glycols; Foods and beverages
Points are the difference in the share of rows rated A or B.
The two materials
PP
Polypropylene
Polypropylene resists most acids, alkalis and salt solutions. Concentrated oxidising acids, chlorinated solvents and aromatic hydrocarbons attack it, and it turns brittle below about 0 °C.
Rated rows: 978. A 66 %, B 11 %, C 15 %, D 8 %
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 | PP: rated A or B | FEP: rated A or B |
|---|---|---|
| Mineral acids | 70 % (63 rows) | 100 % (55 rows) |
| Organic acids | 97 % (64 rows) | 100 % (64 rows) |
| Alkalis | 100 % (22 rows) | 100 % (18 rows) |
| Salts and salt solutions | 99 % (198 rows) | 100 % (197 rows) |
| Oxidising agents and halogens | 72 % (61 rows) | 100 % (52 rows) |
| Alcohols and glycols | 93 % (59 rows) | 100 % (57 rows) |
| Phenols | 79 % (14 rows) | 100 % (14 rows) |
| Ketones and aldehydes | 69 % (35 rows) | 100 % (33 rows) |
| Esters and ethers | 63 % (71 rows) | 100 % (69 rows) |
| Amines and nitrogen compounds | 79 % (39 rows) | 100 % (38 rows) |
| Aromatic hydrocarbons | 14 % (14 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 63 % (78 rows) | 100 % (74 rows) |
| Vegetable and animal oils, fats, essential oils | 75 % (48 rows) | 100 % (47 rows) |
| Halogenated hydrocarbons | 4 % (70 rows) | 90 % (49 rows) |
| Foods and beverages | 100 % (46 rows) | 100 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 172 in total, the first 40 shown.
| Chemical | Concentration | PP | FEP |
|---|---|---|---|
| 1,2-Dibromoethane | D | A | |
| 1,3-Butadiene | D | A | |
| 1-Chloronaphthalene | D | A | |
| Allyl Chloride | 100 % | D | A |
| Amyl Chloride | D | A | |
| Benzyl Alcohol | D | A | |
| Benzyl Chloride | 100 % | D | A |
| Bromine | D | A | |
| Bromine Vapors | D | A | |
| Bromobenzene | D | A | |
| Bromochloromethane | 100 % | D | A |
| Bromoform | D | A | |
| Bromomethane | technical grade | D | A |
| Butene | technical grade | D | A |
| Butyric Acid | D | A | |
| Camphor Oil | D | A | |
| Carbon Disulfide | D | A | |
| Carbon Tetrachloride | D | A | |
| Cedar Oil | D | A | |
| Chlorine | 10 % wet | D | A |
| Chlorine | 97 % | D | A |
| Chlorine Gas | D | A | |
| Chloroethanol | technical grade | D | A |
| Chloromethane (Methyl Chloride) | technical grade | D | A |
| Cinnamon Oil | D | A | |
| Dichloropropane | 100 % | D | A |
| Diethyl Ether | technical grade | D | A |
| Diethylbenzene | D | A | |
| Diisooctyl Phthalate (DOP) | technical grade | D | A |
| Dimethylaniline | D | A | |
| Dioctyl Adipate | D | A | |
| Diphenyl Ether | D | A | |
| Diphyl | D | A | |
| Ethyl Acrylate | 100 % | D | A |
| Fluorine | D | A | |
| Furfural | D | A | |
| Hydrogen Peroxide | 100 % | D | A |
| Nitric Acid | 66 % | D | A |
| Nitric Acid | 70 % | D | A |
| Oleum (Fuming Sulfuric Acid) | 10 % SO3 | 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 PP or FEP more chemical-resistant?
Of 904 chemicals rated for both materials at 20 °C, PP and FEP share the same rating in 621 rows (69 %). PP is rated better in 0 rows and FEP in 283 rows.
How do PP and FEP compare for chemical resistance?
Based on 904 chemicals tested for both: PP is rated better with –. FEP is rated better with Halogenated hydrocarbons, Aromatic hydrocarbons, Fuels, mineral oils and aliphatic hydrocarbons, Esters and ethers. They perform similarly with Organic acids, Alkalis, Salts and salt solutions, Alcohols and glycols.
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.