Glycidyl Methacrylate (GMA) CAS: 106-91-2
Glycidyl methacrylate (GMA, CAS 106-91-2) is a colorless liquid with a fruity odor, characterized by its bifunctional structure containing both a reactive epoxide ring and a polymerizable methacrylate double bond . This dual functionality makes it a highly versatile monomer used primarily as a crosslinking agent and adhesion promoter in the production of durable epoxy and acrylic resins . Key applications span powder and industrial coatings, adhesives, and dental composite materials, where it enhances mechanical strength and substrate adhesion . The compound is slightly soluble in water, miscible with most organic solvents, and typically stabilized with an inhibitor (e.g., MEHQ) to prevent premature polymerization during storage .
1. Overview
GMA is a colorless liquid monomer containing both an epoxy group and a methacrylate group. This dual functionality makes it highly valuable as a reactive intermediate for polymer modification, crosslinking, and adhesion promotion.
2. Key Features
Dual reactivity – epoxy ring opens with acids/amines; methacrylate double bond undergoes free-radical polymerization
Excellent adhesion promoter – improves bonding to metals, glass, and fillers
Crosslinking agent – introduces reactive sites for post-polymerization crosslinking
Low viscosity – easy to handle and blend
High purity grades available (≥97% – ≥99.5%)
3. Key Specifications
| Parameter | Typical Value | Explanation |
|---|---|---|
| Appearance | Colorless liquid | Darkening indicates degradation |
| Assay (Purity) | ≥97% – ≥99.5% | Higher purity for consistent polymerization |
| Epoxy Value | ≥0.5 – 0.65 eq/100g | Measures epoxy group content |
| Water Content | ≤0.1% – ≤0.5% | Low moisture critical for epoxy reactions |
| Inhibitor (MEHQ) | 50 – 200 ppm | Prevents premature polymerization during storage |
| Density (25°C) | 1.04 – 1.07 g/mL | Affects volume-based dosing |
| Viscosity (25°C) | 2 – 5 cP | Very low, easy to pump and mix |
| Refractive Index (n²⁵/D) | 1.448 – 1.452 | Quality indicator |
4. Applications
| Area | Uses |
|---|---|
| Coatings | High-durability automotive and industrial coatings; UV-curable systems |
| Adhesives | Structural adhesives; improves adhesion to difficult substrates |
| Plastic & Rubber Modification | Grafting onto polyolefins (compatibilizers); impact modifier for engineering plastics |
| Composites | Coupling agent for glass fiber and carbon fiber reinforced polymers |
| Powder Coatings | Acrylic powder coatings with GMA provide weatherability and chemical resistance |
| Medical & Dental | Dental adhesives; biomedical hydrogels |
| Electronics | Encapsulants, photoresists, and solder masks |
5. Grade Comparison
| Grade | Purity | Inhibitor | Typical Use |
|---|---|---|---|
| Standard Industrial | ≥97% | 100–200 ppm MEHQ | General polymer modification, coatings |
| High Purity | ≥99% | 50–100 ppm MEHQ | Adhesives, medical devices |
| Stabilized | ≥97% | 200–300 ppm MEHQ | Long-term storage, bulk transport |
6. Buying Guide
Select by application:
Coatings/adhesives → Standard grade (≥97%) sufficient
Medical/dental → High purity (≥99%) with low inhibitor
Long-term storage → Stabilized grade with higher inhibitor
Storage & Handling:
Store at 2–8°C (refrigeration required) – polymerizes at room temperature over time
Keep container tightly sealed – moisture sensitive
Avoid light and heat
Shelf life: 6–12 months refrigerated
Toxic – GHS: H302 (harmful), H315 (skin irritation), H317 (allergic), H335 (respiratory)
Quality checks:
Request CoA for purity, epoxy value, water content, inhibitor level
Check inhibitor level – too low risks premature polymerization; too high may affect cure
7. FAQ
Q: Why does GMA need to be refrigerated?
A: GMA polymerizes spontaneously at room temperature. Refrigeration (2–8°C) slows polymerization. Inhibitor (MEHQ) further stabilizes. Do not freeze.
Q: What is the shelf life of GMA?
A: 6–12 months when stored refrigerated (2–8°C) in original sealed container. Unrefrigerated shelf life is weeks to months.
Q: How is GMA different from GMA-based resins?
A: GMA monomer is the pure, reactive liquid. GMA resin is a polymer (e.g., poly-GMA) or copolymer. Monomer is used for grafting; resin for final properties.
Q: Is GMA hazardous to handle?
A: Yes. GHS: H302 (harmful if swallowed), H315 (skin irritation), H317 (may cause allergic skin reaction), H335 (respiratory irritation). Use PPE (gloves, goggles, fume hood).
Q: How does GMA improve adhesion?
A: The epoxy group reacts with surface hydroxyls (-OH) on metals, glass, and fillers, forming strong covalent bonds. The methacrylate group polymerizes with the matrix resin, creating a chemical bridge.
Q: Can GMA be used in water-based systems?
A: GMA is hydrophobic and not water-soluble. It requires organic solvents or emulsification for waterborne applications.
Q: What happens if GMA freezes?
A: Freezing may cause cracking and air introduction, but product quality is typically unaffected if thawed gently. Avoid repeated freeze-thaw cycles.
8. Delivery & Service
Packaging: 25kg HDPE drum, 200kg steel drum, 1000kg IBC
Documentation: CoA (purity, epoxy value, water, inhibitor), MSDS, TDS
Certifications: ISO 9001 (varies by supplier)
Shipping: Class 3 flammable liquid (UN 2810); requires hazardous documentation. Ship refrigerated or insulated.
| Glycidyl methacrylate Chemical Properties |
| Melting point | -52°C |
| Boiling point | 189 °C(lit.) |
| density | 1.075 g/mL at 20 °C |
| vapor pressure | 4.2hPa at 25℃ |
| refractive index | n |
| Fp | 169 °F |
| storage temp. | 2-8°C |
| solubility | Chloroform (Slightly), Methanol (Slightly) |
| form | Liquid |
| color | Clear |
| Water Solubility | 0.5-1.0 g/100 mL at 20 ºC |
| BRN | 2506 |
| Henry's Law Constant | 3.2×101 mol/(m3Pa) at 25℃, HSDB (2015) |
| Exposure limits | MAC: 5 mg/m3 |
| Stability: | Unstable. Light sensitive. May be stabilized with around 100ppm MEHQ. Refrigerate. |
| InChI | 1S/C7H10O3/c1-5(2)7(8)10-4-6-3-9-6/h6H,1,3-4H2,2H3 |
| InChIKey | VOZRXNHHFUQHIL-UHFFFAOYSA-N |
| SMILES | CC(=C)C(=O)OCC1CO1 |
| LogP | 0.96 at 25℃ |
| CAS DataBase Reference | 106-91-2(CAS DataBase Reference) |
| IARC | 2A (Vol. 125) In prep. |
| NIST Chemistry Reference | 2-Propenoic acid, 2-methyl-, oxiranylmethyl ester(106-91-2) |
| EPA Substance Registry System | Glycidyl methacrylate (106-91-2) |
| Safety Information |
| Hazard Codes | Xn,T,T+ |
| Risk Statements | 20/21/22-36/38-43-60-45-68-39/26-34 |
| Safety Statements | 26-28-28A-45-36/37-53-36/37/39 |
| RIDADR | UN 2810 6.1/PG 3 |
| WGK Germany | 2 |
| RTECS | OZ4375000 |
| TSCA | TSCA listed |
| HazardClass | 8 |
| PackingGroup | III |
| HS Code | 29161490 |
| Storage Class | 6.1C - Combustible acute toxic Cat.3 toxic compounds or compounds which causing chronic effects |
| Hazard Classifications | Acute Tox. 3 Dermal Acute Tox. 4 Oral Carc. 1B Eye Dam. 1 Muta. 2 Repr. 1B Skin Corr. 1C Skin Sens. 1 STOT RE 1 STOT SE 3 |
| Hazardous Substances Data | 106-91-2(Hazardous Substances Data) |
| Toxicity | dog,LCLo,inhalation,1400mg/m3/6H (1400mg/m3),LUNGS, THORAX, OR RESPIRATION: OTHER CHANGES,National Technical Information Service. Vol. OTS0530684, |
