Summary
- FEP is rated better with
- Halogenated hydrocarbons (+80 points); Aromatic hydrocarbons (+67 points); Phenols (+38 points); Vegetable and animal oils, fats, essential oils (+29 points); Esters and ethers (+27 points); Oxidising agents and halogens (+22 points); Mineral acids (+21 points); Fuels, mineral oils and aliphatic hydrocarbons (+21 points); Ketones and aldehydes (+16 points)
- Within 10 points of each other
- Organic acids; Alkalis; Salts and salt solutions; Alcohols and glycols; Amines and nitrogen compounds; Foods and beverages
Points are the difference in the share of rows rated A or B.
The two materials
HDPE
High-density polyethylene
High-density polyethylene resists most aqueous acids, alkalis and salt solutions. Strong oxidising acids, chlorinated solvents and aromatic hydrocarbons attack or swell it. Continuous service is usually limited to about 80 °C.
Rated rows: 686. A 82 %, B 3 %, C 9 %, D 6 %
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 | HDPE: rated A or B | FEP: rated A or B |
|---|---|---|
| Mineral acids | 79 % (56 rows) | 100 % (55 rows) |
| Organic acids | 95 % (58 rows) | 100 % (64 rows) |
| Alkalis | 100 % (22 rows) | 100 % (18 rows) |
| Salts and salt solutions | 100 % (193 rows) | 100 % (197 rows) |
| Oxidising agents and halogens | 78 % (40 rows) | 100 % (52 rows) |
| Alcohols and glycols | 93 % (43 rows) | 100 % (57 rows) |
| Phenols | 62 % (8 rows) | 100 % (14 rows) |
| Ketones and aldehydes | 84 % (19 rows) | 100 % (33 rows) |
| Esters and ethers | 73 % (37 rows) | 100 % (69 rows) |
| Amines and nitrogen compounds | 90 % (21 rows) | 100 % (38 rows) |
| Aromatic hydrocarbons | 33 % (9 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 79 % (38 rows) | 100 % (74 rows) |
| Vegetable and animal oils, fats, essential oils | 71 % (21 rows) | 100 % (47 rows) |
| Halogenated hydrocarbons | 10 % (31 rows) | 90 % (49 rows) |
| Foods and beverages | 100 % (32 rows) | 100 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 91 in total, the first 40 shown.
| Chemical | Concentration | HDPE | FEP |
|---|---|---|---|
| 1,2-Dibromoethane | D | A | |
| Acetic Anhydride | technical grade | D | A |
| Bromine | D | A | |
| Bromine Vapors | D | A | |
| Bromochloromethane | 100 % | D | A |
| Bromoform | D | A | |
| Butanetriol | 100 % | D | A |
| Butene | technical grade | D | A |
| Camphor Oil | D | A | |
| Carbon Disulfide | D | A | |
| Carbon Tetrachloride | D | A | |
| Chlorine | 97 % | D | A |
| Chlorine Gas | D | A | |
| Dichloroethylene | technical grade | D | A |
| Dichloroisopropyl Ether | D | A | |
| Dichloromethane | D | A | |
| Diisooctyl Phthalate (DOP) | technical grade | D | A |
| Dimethyl Phthalate (DMP) | 100 % | D | A |
| Essential Oils | D | A | |
| Ethyl Acrylate | 100 % | D | A |
| Fluorine | D | A | |
| Oleum (Fuming Sulfuric Acid) | 10 % SO3 | D | A |
| Oleum Vapors | low concentration | D | A |
| Perchloroethylene (PCE) | D | A | |
| Styrene | 100 % | D | A |
| Sulfuric Acid | fuming | D | A |
| Tetrabromoethane | 100 % | D | A |
| Thionyl Chloride | technical grade | D | A |
| Trichlorobenzene | 100 % | D | A |
| Vinylidene Chloride | D | A | |
| 1,2-Dichlorobenzene | C | A | |
| 1,3-Butadiene | C | A | |
| Acetaldehyde | 40 % | C | A |
| Acetaldehyde | technical grade | C | A |
| Allyl Chloride | 100 % | C | A |
| Amyl Chloride | C | A | |
| Aqua Regia | D | B | |
| Benzene | C | A | |
| Benzyl Alcohol | C | A | |
| Bromobenzene | C | 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 HDPE or FEP more chemical-resistant?
Of 667 chemicals rated for both materials at 20 °C, HDPE and FEP share the same rating in 548 rows (82 %). HDPE is rated better in 2 rows and FEP in 117 rows.
How do HDPE and FEP compare for chemical resistance?
Based on 667 chemicals tested for both: HDPE is rated better with –. FEP is rated better with Halogenated hydrocarbons, Aromatic hydrocarbons, Phenols, Vegetable and animal oils, fats, essential oils. 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.