Summary
- Nylon (PA) is rated better with
- Alkalis (+15 points)
- Acetal (POM) is rated better with
- Ketones and aldehydes (+38 points); Alcohols and glycols (+29 points); Amines and nitrogen compounds (+24 points); Oxidising agents and halogens (+17 points); Halogenated hydrocarbons (+17 points)
- Within 10 points of each other
- Mineral acids; Organic acids; Salts and salt solutions; Phenols; Esters and ethers; 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 %
Acetal (POM)
Polyoxymethylene (acetal)
Acetal (POM) resists many organic solvents and fuels. Strong acids and oxidising agents degrade it.
Rated rows: 956. A 41 %, B 32 %, C 12 %, D 15 %
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 | Acetal (POM): rated A or B |
|---|---|---|
| Mineral acids | 5 % (63 rows) | 5 % (63 rows) |
| Organic acids | 25 % (63 rows) | 34 % (64 rows) |
| Alkalis | 91 % (22 rows) | 76 % (21 rows) |
| Salts and salt solutions | 78 % (194 rows) | 76 % (197 rows) |
| Oxidising agents and halogens | 26 % (62 rows) | 43 % (63 rows) |
| Alcohols and glycols | 67 % (58 rows) | 96 % (57 rows) |
| Phenols | 8 % (13 rows) | 0 % (14 rows) |
| Ketones and aldehydes | 53 % (32 rows) | 91 % (35 rows) |
| Esters and ethers | 80 % (65 rows) | 88 % (68 rows) |
| Amines and nitrogen compounds | 50 % (34 rows) | 74 % (38 rows) |
| Aromatic hydrocarbons | 100 % (14 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 97 % (73 rows) | 96 % (73 rows) |
| Vegetable and animal oils, fats, essential oils | 98 % (46 rows) | 100 % (45 rows) |
| Halogenated hydrocarbons | 63 % (70 rows) | 80 % (70 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: 109 in total, the first 40 shown.
| Chemical | Concentration | Nylon (PA) | Acetal (POM) |
|---|---|---|---|
| Acetic Acid | 10 % | D | A |
| Acetic Acid | 5 % | D | A |
| Benzyl Alcohol | D | A | |
| Calcium Hypochlorite | aqueous | D | A |
| Cetyl Alcohol | 100 % | D | A |
| Chlorobenzene | D | A | |
| Chloromethane (Methyl Chloride) | technical grade | D | A |
| Developer Fluids | D | A | |
| Epichlorohydrin | 100 % | D | A |
| Gear Oil, EP (Hypoid), 110°C | A | D | |
| Iodine Tincture | D | A | |
| Isopropyl Ether | technical grade | D | A |
| Methylamine | 32 % | D | A |
| Perchloroethylene (PCE) | D | A | |
| Photo Developer | D | A | |
| Potassium Permanganate | D | A | |
| Potassium Permanganate | aqueous | D | A |
| Propylene Glycol | D | A | |
| Salicylic Acid | saturated | A | D |
| Soap Solution | any concentration | D | A |
| Sodium Bisulfite | aqueous | A | D |
| Sodium Metabisulfite | any concentration | A | D |
| Tannin | A | D | |
| Tannin | 10 % | A | D |
| Tanning Extracts | A | D | |
| Vegetable Tanning Extracts | usual technical grade | A | D |
| Vinegar | D | A | |
| Acetonitrile | A | C | |
| Acetylsalicylic Acid (Aspirin) | 100 % | A | C |
| Acrylonitrile | A | C | |
| Allyl Acetate | 100 % | D | B |
| Aluminum Chloride | 10 % | A | C |
| Aluminum Nitrate | aqueous | A | C |
| Aluminum Sulfate | 10 % | A | C |
| Ammonium Bifluoride | 50 % | B | D |
| Ammonium Hydroxide (Ammonia Solution) | C | A | |
| Ammonium Hydroxide (Ammonia Solution) | 30 % | C | A |
| Ammonium Iron(III) Sulfate | saturated | A | C |
| Ammonium Persulfate | saturated | D | B |
| Ammonium Persulfate | aqueous | D | B |
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 Acetal (POM) more chemical-resistant?
Of 930 chemicals rated for both materials at 20 °C, Nylon (PA) and Acetal (POM) share the same rating in 538 rows (58 %). Nylon (PA) is rated better in 181 rows and Acetal (POM) in 211 rows.
How do Nylon (PA) and Acetal (POM) compare for chemical resistance?
Based on 930 chemicals tested for both: Nylon (PA) is rated better with Alkalis. Acetal (POM) is rated better with Ketones and aldehydes, Alcohols and glycols, Amines and nitrogen compounds, Oxidising agents and halogens. They perform similarly with Mineral acids, Organic acids, Salts and salt solutions, Phenols.
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.