Summary
- FEP is rated better with
- Aromatic hydrocarbons (+80 points); Halogenated hydrocarbons (+79 points); Vegetable and animal oils, fats, essential oils (+37 points); Ketones and aldehydes (+37 points); Fuels, mineral oils and aliphatic hydrocarbons (+34 points); Phenols (+33 points); Esters and ethers (+32 points); Mineral acids (+29 points); Oxidising agents and halogens (+24 points); Alcohols and glycols (+11 points)
- Within 10 points of each other
- Organic acids; Alkalis; Salts and salt solutions; Amines and nitrogen compounds; Foods and beverages
Points are the difference in the share of rows rated A or B.
The two materials
LDPE
Low-density polyethylene
Low-density polyethylene has a similar profile to HDPE but is softer and more permeable, so solvents swell it sooner. Continuous service is usually limited to about 60 °C.
Rated rows: 678. A 78 %, B 4 %, C 11 %, 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 | LDPE: rated A or B | FEP: rated A or B |
|---|---|---|
| Mineral acids | 71 % (48 rows) | 100 % (55 rows) |
| Organic acids | 93 % (59 rows) | 100 % (64 rows) |
| Alkalis | 100 % (22 rows) | 100 % (18 rows) |
| Salts and salt solutions | 99 % (187 rows) | 100 % (197 rows) |
| Oxidising agents and halogens | 76 % (38 rows) | 100 % (52 rows) |
| Alcohols and glycols | 89 % (46 rows) | 100 % (57 rows) |
| Phenols | 67 % (9 rows) | 100 % (14 rows) |
| Ketones and aldehydes | 63 % (19 rows) | 100 % (33 rows) |
| Esters and ethers | 68 % (41 rows) | 100 % (69 rows) |
| Amines and nitrogen compounds | 95 % (19 rows) | 100 % (38 rows) |
| Aromatic hydrocarbons | 20 % (10 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 66 % (41 rows) | 100 % (74 rows) |
| Vegetable and animal oils, fats, essential oils | 63 % (19 rows) | 100 % (47 rows) |
| Halogenated hydrocarbons | 11 % (36 rows) | 90 % (49 rows) |
| Foods and beverages | 100 % (30 rows) | 100 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 112 in total, the first 40 shown.
| Chemical | Concentration | LDPE | FEP |
|---|---|---|---|
| 1,2-Dibromoethane | D | A | |
| 1,3-Butadiene | 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 |
| Butyric Acid | D | A | |
| Camphor Oil | D | A | |
| Carbon Disulfide | D | A | |
| Carbon Tetrachloride | D | A | |
| Cedar Oil | D | A | |
| Chlorine | 97 % | D | A |
| Chlorine Gas | D | A | |
| Chloroform | 100 % | D | A |
| Cinnamon Oil | D | A | |
| Cresol | D | A | |
| Dichloroethylene | technical grade | D | A |
| Dichloroisopropyl Ether | D | A | |
| Dichloromethane | D | A | |
| Diethyl Ether | technical grade | D | A |
| Diethylbenzene | D | A | |
| Diisooctyl Phthalate (DOP) | technical grade | D | A |
| Ethyl Acrylate | 100 % | D | A |
| Ethyl Glycol | 100 % | D | A |
| Fluorine | D | A | |
| n-Hexane | D | A | |
| Nitrobenzene | D | A | |
| Oleum (Fuming Sulfuric Acid) | 10 % SO3 | D | A |
| Perchloroethylene (PCE) | D | A | |
| Propane | gaseous | D | A |
| Sulfur Dioxide | liquid | D | A |
| Sulfuric Acid | fuming | D | A |
| Tetrahydrofuran (THF) | D | A | |
| Tetrahydronaphthalene | technical grade | D | A |
| Thionyl Chloride | technical grade | 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 LDPE or FEP more chemical-resistant?
Of 653 chemicals rated for both materials at 20 °C, LDPE and FEP share the same rating in 515 rows (79 %). LDPE is rated better in 0 rows and FEP in 138 rows.
How do LDPE and FEP compare for chemical resistance?
Based on 653 chemicals tested for both: LDPE is rated better with –. FEP is rated better with Aromatic hydrocarbons, Halogenated hydrocarbons, Vegetable and animal oils, fats, essential oils, Ketones and aldehydes. They perform similarly with Organic acids, Alkalis, Salts and salt solutions, Amines and nitrogen compounds.
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.