# Acrylic acid: Characteristics

Ester grade versus glacial: why purity splits markets

Source page: https://www.materialinsights.org/chemicals/acrylic_acid/characteristics/

What this tab covers The physical and chemical properties that set its grade, price and uses, with the commercial grades and the standards that define them.

Two grades dominate: crude (ester grade) for making esters and glacial for SAP and polymers. Inhibitor content, dimer formation and freezing point drive storage and handling.

#### Properties that matter commercially

| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| **Purity** | glacial AA at least 99.5%; ester-grade crude about 98% (indicative) | SAP needs low aldehydes and dimer. | industry standard (indicative) |
| **Freezing point** | 13°C | Must be kept warm, but not too warm, to prevent polymerisation. | standard physical data |
| **Inhibitor** | about 200 ppm MEHQ (hydroquinone monomethyl ether), needs dissolved oxygen | Prevents runaway polymerisation. | industry standard (indicative) |
| **Dimer formation** | diacrylic acid forms during storage | Limits shelf life to weeks or months. | industry standard |

#### Commercial grades

- Glacial acrylic acid (GAA)
- Crude/ester-grade acrylic acid
- Acrylate esters: n-butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, methyl acrylate
- SAP

## Other sections

- [Summary](https://www.materialinsights.org/chemicals/acrylic_acid/index.md)
- [Overview](https://www.materialinsights.org/chemicals/acrylic_acid/overview/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/acrylic_acid/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/acrylic_acid/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/acrylic_acid/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/acrylic_acid/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/acrylic_acid/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/acrylic_acid/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/acrylic_acid/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/acrylic_acid/regulation/index.md)
- [Emissions](https://www.materialinsights.org/chemicals/acrylic_acid/emissions/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/acrylic_acid/links/index.md)