2-Hydroxyethyl Acrylate (commonly known as 2-HEA, CAS No. 818-61-1) is a versatile, clear, and colorless functional acrylic monomer bearing both a highly reactive acrylic double bond and a primary hydroxyl functional group (-OH). With the molecular formula C5H8O3 and a molecular weight of 116.12 g/mol, 2-HEA serves as an essential building block in modern polymer chemistry, particularly in the synthesis of thermosetting acrylic resins, radiation-curable formulations, and performance-driven specialty polymers.
In the global specialty chemicals market, 2-HEA is widely prized by formulators and chemical engineers for its unique dual functionality: the acrylate vinyl moiety allows rapid copolymerization with various acrylic, vinylic, and methacrylic comonomers, while the terminal primary hydroxyl group offers active crosslinking sites for polyisocyanates, melamine-formaldehyde crosslinkers, and epoxy curing agents.
Key Physical and Chemical Specifications
To ensure premium formulation performance, DECHEM produces 2-HEA adhering to strict international quality standards. The key technical parameters include:
| Property | Standard Value / Unit | Test Method |
|---|---|---|
| Chemical Name | 2-Hydroxyethyl Acrylate (2-HEA) | IUPAC Standard |
| CAS Number | 818-61-1 | Chemical Abstracts Service |
| Purity (Assay by GC) | ≥ 97.0% (93% grade also available) | Gas Chromatography (GC) |
| Molecular Weight | 116.12 g/mol | Theoretical Calculation |
| Appearance | Clear, colorless transparent liquid | Visual Inspection |
| Water Content (Moisture) | ≤ 0.10 wt% | Karl Fischer (ASTM E203) |
| Acid Value (as Acrylic Acid) | ≤ 1.0 mg KOH/g | Acid-Base Titration |
| Inhibitor (MEHQ) | 200–400 ppm (customizable) | HPLC / Spectrophotometry |
Core Industrial Applications of 2-HEA
1. Automotive OEM & Refinish Clearcoats
In automotive coatings, 2-HEA is copolymerized with methyl methacrylate (MMA), butyl acrylate (BA), and styrene to produce hydroxy-functional acrylic polyols. When crosslinked with aliphatic polyisocyanates (such as HDI biuret or trimer), the resulting polyurethane network delivers exceptional high-gloss retention, scratch resistance, chemical durability against acid rain, and superior outdoor weathering.
2. UV/EB Radiation-Curable Coatings and Inks
2-HEA serves as an active reactive diluent and modifying monomer in ultraviolet (UV) and electron-beam (EB) cured printing inks, wood finishes, and overprint varnishes. Its low viscosity significantly reduces formulation viscosity without volatile organic solvents, while the acrylate double bond ensures ultra-fast radical polymerization under UV light exposure.
3. Pressure-Sensitive Adhesives (PSA) & Emulsions
Because the homopolymer of 2-HEA possesses a low glass transition temperature (Tg of -15°C), copolymerizing 2-HEA into acrylic adhesives imparts remarkable flexibility, low-temperature tack, and peel strength. Furthermore, the hydroxyl functionality provides vital polar anchoring onto metal, glass, and plastic substrates.
4. Textile Finishing and Leather Treatment Agents
2-HEA is widely utilized in textile binding resins and leather finishing polyacrylates to enhance washability, soft-hand feel, abrasion resistance, and fiber adhesion.
Handling, Packaging, and Quality Assurance at DECHEM
Due to the thermal reactivity of acrylic double bonds, 2-HEA requires stabilized storage under controlled conditions. DECHEM supplies 2-HEA with precisely calibrated MEHQ inhibitor levels in ISO tanks (20–24 MT), IBC totes (1,000 kg), and heavy-duty steel drums (200 kg), exported directly from the Qingdao maritime logistics hub to over 50 global destinations.
- Strict Moisture Control: moisture content strictly held below 0.10% to prevent unwanted side reactions in sensitive isocyanate-cured systems.
- Low Diester Impurities: advanced distillation minimizes Diethylene Glycol Diacrylate (DEGDA) to prevent premature gelation and resin cloudiness.
Frequently Asked Questions (FAQ) on 2-HEA
Q: What is the main difference between 2-HEA and HEMA?
A: 2-HEA is an acrylate with a low Tg (-15°C) offering higher flexibility and faster cure rates, whereas HEMA is a methacrylate with a higher Tg (+55°C) offering greater hardness and thermal stability.
Q: What is the typical shelf life of 2-HEA?
A: When stored below 25°C in original unopened containers away from direct sunlight, stabilized 2-HEA has a shelf life of up to 12 months.