Summary
- PP is rated better with
- Alkalis (+76 points); Mineral acids (+54 points); Salts and salt solutions (+47 points); Organic acids (+30 points); Oxidising agents and halogens (+27 points)
- Aluminium is rated better with
- Aromatic hydrocarbons (+86 points); Fuels, mineral oils and aliphatic hydrocarbons (+37 points); Esters and ethers (+31 points); Ketones and aldehydes (+28 points); Vegetable and animal oils, fats, essential oils (+25 points); Halogenated hydrocarbons (+23 points); Amines and nitrogen compounds (+16 points)
- Within 10 points of each other
- Alcohols and glycols; Phenols; 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 %
Aluminium
Aluminium
Aluminium relies on a thin oxide layer. Strong acids, strong alkalis and mercury compounds destroy that layer.
Rated rows: 968. A 60 %, B 9 %, C 16 %, D 16 %
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 | Aluminium: rated A or B |
|---|---|---|
| Mineral acids | 70 % (63 rows) | 16 % (63 rows) |
| Organic acids | 97 % (64 rows) | 67 % (64 rows) |
| Alkalis | 100 % (22 rows) | 24 % (21 rows) |
| Salts and salt solutions | 99 % (198 rows) | 52 % (194 rows) |
| Oxidising agents and halogens | 72 % (61 rows) | 45 % (62 rows) |
| Alcohols and glycols | 93 % (59 rows) | 98 % (59 rows) |
| Phenols | 79 % (14 rows) | 86 % (14 rows) |
| Ketones and aldehydes | 69 % (35 rows) | 97 % (35 rows) |
| Esters and ethers | 63 % (71 rows) | 94 % (71 rows) |
| Amines and nitrogen compounds | 79 % (39 rows) | 95 % (39 rows) |
| Aromatic hydrocarbons | 14 % (14 rows) | 100 % (14 rows) |
| Fuels, mineral oils and aliphatic hydrocarbons | 63 % (78 rows) | 100 % (78 rows) |
| Vegetable and animal oils, fats, essential oils | 75 % (48 rows) | 100 % (48 rows) |
| Halogenated hydrocarbons | 4 % (70 rows) | 27 % (71 rows) |
| Foods and beverages | 100 % (46 rows) | 96 % (46 rows) |
Where the ratings differ most
Rows where the two ratings at 20 °C are at least two grades apart: 340 in total, the first 40 shown.
| Chemical | Concentration | PP | Aluminium |
|---|---|---|---|
| 1,3-Butadiene | D | A | |
| Allyl Chloride | 100 % | D | A |
| Aluminum Chloride | 10 % | A | D |
| Aluminum Chloride | solid | A | D |
| Aluminum Chloride | saturated | A | D |
| Aluminum Nitrate | aqueous | A | D |
| Ammonium Dihydrogen Phosphate | any concentration | A | D |
| Ammonium Fluoride | saturated | A | D |
| Ammonium Fluoride | aqueous | A | D |
| Ammonium Iron(II) Sulfate | A | D | |
| Ammonium Iron(III) Sulfate | saturated | A | D |
| Ammonium Persulfate | saturated | A | D |
| Ammonium Persulfate | aqueous | A | D |
| Aniline Hydrochloride | saturated | A | D |
| Antimony Trichloride | 90 % | A | D |
| Antimony Trichloride | aqueous | A | D |
| Arsenic Acid | A | D | |
| Arsenic Acid | aqueous | A | D |
| Benzyl Alcohol | D | A | |
| Bismuth Chloride | A | D | |
| Bromobenzene | D | A | |
| Butene | technical grade | D | A |
| Butyric Acid | D | A | |
| Cadmium Bromide | A | D | |
| Calcium Hypochlorite | A | D | |
| Calcium Hypochlorite | saturated | A | D |
| Calcium Hypochlorite | aqueous | A | D |
| Camphor Oil | D | A | |
| Carbon Disulfide | D | A | |
| Carbon Tetrachloride | D | A | |
| Cedar Oil | D | A | |
| Chloric Acid | 20 % | A | D |
| Chloroacetic Acid | A | D | |
| Chloroacetic Acid | 50 % | A | D |
| Cinnamon Oil | D | A | |
| Clophen A60 (PCB) | D | A | |
| Copper Acetate | aqueous | A | D |
| Copper Sulfate (Copper Vitriol) | aqueous | A | D |
| Copper(I) Chloride | aqueous | A | D |
| Copper(II) Chloride | saturated | A | D |
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 Aluminium more chemical-resistant?
Of 966 chemicals rated for both materials at 20 °C, PP and Aluminium share the same rating in 434 rows (45 %). PP is rated better in 287 rows and Aluminium in 245 rows.
How do PP and Aluminium compare for chemical resistance?
Based on 966 chemicals tested for both: PP is rated better with Alkalis, Mineral acids, Salts and salt solutions, Organic acids. Aluminium is rated better with Aromatic hydrocarbons, Fuels, mineral oils and aliphatic hydrocarbons, Esters and ethers, Ketones and aldehydes. They perform similarly with Alcohols and glycols, Phenols, Foods and beverages.
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.