Ethylene Glycol Methacrylate, 2-Hydroxyethyl Methacrylate, Glycol Methacrylate, HEMA, 868-77-9
2-HYDROXYETHYL METHACRYLATE (HEMA)
CAS Number: 868-77-9
EC Number (EINECS): 212-782-2
Molecular Formula: C₆H₁₀O₃
Molecular Weight: 130.14 g/mol
Chemical Class: Methacrylate ester (monomer)
SECTION 1: PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY
| Parameter |
Description |
| Chemical Name (IUPAC) |
2-Hydroxyethyl 2-methylprop-2-enoate |
| Other Names |
HEMA, 2-Hydroxyethyl Methacrylate, Ethylene glycol methacrylate, Methacrylic acid 2-hydroxyethyl ester, Glycol methacrylate |
| CAS Number |
868-77-9 |
| EC Number (EINECS) |
212-782-2 |
| Molecular Formula |
C₆H₁₀O₃ |
| Molecular Weight |
130.14 g/mol |
| Chemical Class |
Methacrylate ester (monomer) |
| Structure |
CH₂=C(CH₃)-COO-CH₂-CH₂OH |
| Appearance |
Colorless liquid |
| Odor |
Mild, characteristic |
| Stabilizer |
200 ± 20 ppm MEHQ (Hydroquinone monomethyl ether) |
SECTION 2: PHYSICAL AND CHEMICAL PROPERTIES
| Property |
Value / Range |
| Molecular Formula |
C₆H₁₀O₃ |
| Molecular Weight |
130.14 g/mol |
| Appearance |
Colorless liquid |
| Odor |
Mild, characteristic |
| Density (20°C) |
~1.07 g/cm³ |
| Melting Point |
-12°C |
| Boiling Point |
~250°C (decomposes) |
| Flash Point |
~97°C (closed cup) |
| Vapor Pressure (20°C) |
<0.01 mmHg (very low) |
| Vapor Density (air=1) |
4.5 (heavier than air) |
| Solubility in Water |
Soluble (miscible) |
| Solubility in Organic Solvents |
Soluble in alcohols, ethers, and most organic solvents |
| Refractive Index (n²⁰D) |
~1.451-1.453 |
| Viscosity (25°C) |
~5-7 cP |
| LogP |
~0.19 (hydrophilic) |
| Polymerization Inhibitor |
200 ± 20 ppm MEHQ (Hydroquinone monomethyl ether) |
| Purity |
≥ 97.0% |
| Free Acid (as Methacrylic Acid) |
≤ 0.2% |
| Color (APHA) |
≤ 20 |
| Water Content |
≤ 0.1% |
SECTION 3: SOLUBILITY PROFILE
| Solvent |
Solubility |
Condition |
| Water |
Soluble (miscible) |
All temperatures |
| Methanol |
Completely miscible |
- |
| Ethanol |
Completely miscible |
- |
| Acetone |
Completely miscible |
- |
| Ethyl Acetate |
Completely miscible |
- |
| Toluene |
Completely miscible |
- |
| Chloroform |
Completely miscible |
- |
| Diethyl Ether |
Completely miscible |
- |
| Aliphatic Hydrocarbons |
Limited solubility |
- |
Critical Note: HEMA is soluble in water and most organic solvents due to its hydrophilic hydroxyl group. Its low vapor pressure and high boiling point make it a low-volatility monomer.
SECTION 4: CHEMICAL PROPERTIES AND REACTIONS
| Property |
Description |
| Chemical Class |
Methacrylate ester (monomer) |
| Functional Groups |
Methacrylate (C=C), hydroxyl (-OH), ester (-COOR) |
| Reactivity |
High; readily polymerizes |
| Polymerization |
Free-radical polymerization (bulk, solution, emulsion) |
| Copolymerization |
Copolymerizes with acrylates, methacrylates, styrene, and other vinyl monomers |
| Hydroxyl Reactivity |
Hydroxyl group enables further functionalization |
| Thermal Decomposition |
> 200°C releases CO, CO₂, and irritant vapors |
| Oxidation |
May form peroxides in air |
| Hydrolysis |
Hydrolyzes in acidic/basic media to methacrylic acid and ethylene glycol |
| Esterification |
Reacts with acids to form esters |
| Transesterification |
Reacts with alcohols to form other methacrylate esters |
| Isocyanate Reaction |
Reacts with isocyanates to form urethane methacrylates |
4.1. Key Reactions
| Reaction Type |
Description |
| Radical Polymerization |
Heat or initiator triggered → Poly(HEMA) |
| Copolymerization |
With acrylates, methacrylates, styrene, vinyl acetate |
| Hydrolysis |
Acid/base → Methacrylic acid + Ethylene glycol |
| Esterification |
With acid chlorides → Esters |
| Isocyanate Reaction |
With isocyanates → Urethane methacrylates |
| Hydroxyl Functionalization |
Enables crosslinking and further modifications |
4.2. Polymerization Inhibition
| Parameter |
Information |
| Stabilizer |
200 ± 20 ppm MEHQ (Hydroquinone monomethyl ether) |
| Stabilizer Function |
Prevents premature free-radical polymerization |
| Dissolved Oxygen |
Acts as additional inhibitor |
| Storage Temp |
15–25°C |
| Inhibitor Removal |
Can be removed by distillation or inhibitor removal column |
SECTION 5: MAJOR APPLICATIONS AND END-USES
5.1. Coatings (Primary Application)
| Application |
Function |
Suitability |
| Thermosetting Acrylic Coatings |
Co-monomer for crosslinkable coatings |
High |
| Photocurable Coatings |
Co-monomer for UV-curable systems |
High |
| Photosensitive Coatings |
Co-monomer for photoresists |
High |
| Industrial Coatings |
Co-monomer for durable coatings |
High |
| Automotive Coatings |
Co-monomer for high-performance coatings |
High |
| Wood Coatings |
Co-monomer for protective coatings |
High |
5.2. Adhesives
| Application |
Function |
Suitability |
| Acrylic Adhesives |
Co-monomer or reactive diluent |
High |
| Structural Adhesives |
Co-monomer for high-strength bonds |
High |
| Anaerobic Adhesives |
Co-monomer for threadlockers |
High |
| Pressure-Sensitive Adhesives |
Co-monomer for tackiness |
High |
| UV-Curable Adhesives |
Reactive diluent |
High |
5.3. Textile and Paper
| Application |
Function |
Suitability |
| Textile Treatment Agents |
Co-monomer for durable finishes |
High |
| Paper Processing |
Co-monomer for paper coatings |
High |
| Fabric Sizing |
Co-monomer for sizing agents |
High |
5.4. Water Quality and Polymer Materials
| Application |
Function |
Suitability |
| Water Quality Stabilizers |
Co-monomer for scale inhibitors |
High |
| Macromolecular Materials |
Co-monomer for functional polymers |
High |
| Hydrogels |
Monomer for biocompatible hydrogels |
High |
| Contact Lenses |
Monomer for hydrophilic contact lenses |
High |
5.5. Specialty Applications
| Application |
Function |
Suitability |
| Dental Materials |
Monomer for dental composites |
High |
| Medical Adhesives |
Monomer for biocompatible adhesives |
High |
| Drug Delivery Systems |
Monomer for controlled-release systems |
High |
| Bone Cements |
Co-monomer for PMMA bone cements |
High |
| Microencapsulation |
Monomer for microcapsule shells |
High |
| Inkjet Inks |
Co-monomer for UV-curable inks |
High |
| 3D Printing Resins |
Co-monomer for stereolithography (SLA) resins |
High |
SECTION 6: INDUSTRY SUITABILITY MATRIX
| Industry |
Suitability |
Explanation |
| Coatings |
High |
Thermosetting, photocurable, and photosensitive coatings |
| Adhesives |
High |
UV-curable and structural adhesives |
| Textile |
High |
Textile treatment agents and finishes |
| Paper |
High |
Paper processing and coatings |
| Water Treatment |
High |
Water quality stabilizers |
| Medical / Dental |
High |
Contact lenses, dental composites, bone cements |
| Electronics |
High |
Photoresists and photosensitive coatings |
| 3D Printing |
High |
SLA resins and UV-curable inks |
| Cosmetics |
Limited |
Not widely used in cosmetics |
| Food |
Not suitable |
Not used as food additive |
SECTION 7: COMPARISON OF HYDROXYALKYL METHACRYLATES
| Property |
HEMA (2-Hydroxyethyl) |
HPMA (2-Hydroxypropyl) |
HEAM (2-Hydroxyethyl Acrylate) |
| Molecular Formula |
C₆H₁₀O₃ |
C₇H₁₂O₃ |
C₅H₈O₃ |
| Molecular Weight |
130.14 g/mol |
144.17 g/mol |
116.12 g/mol |
| Hydroxyl Content |
High |
High |
High |
| Water Solubility |
Soluble |
Soluble |
Soluble |
| Viscosity |
Low |
Moderate |
Low |
| Glass Transition (Tg) |
~55°C (polymer) |
~26°C (polymer) |
~15°C (polymer) |
| Primary Use |
Coatings, adhesives, hydrogels |
Coatings, adhesives |
Coatings, adhesives |
SECTION 8: OTHER NAMES AND IDENTIFIERS
| Type |
Name / Description |
| IUPAC Name |
2-Hydroxyethyl 2-methylprop-2-enoate |
| Commercial Names |
HEMA, 2-Hydroxyethyl Methacrylate, Glycol Methacrylate |
| Synonyms |
Ethylene glycol methacrylate, Methacrylic acid 2-hydroxyethyl ester |
| CAS Number |
868-77-9 |
| EC Number |
212-782-2 |
| RTECS Number |
OZ4725000 |
| HS Code |
29161400 |
SECTION 9: TOXICOLOGY AND HEALTH EFFECTS
| Parameter |
Value / Description |
| GHS Classification |
Warning |
| Signal Word |
Warning |
| Hazard Statements |
H315 (Causes skin irritation), H317 (May cause allergic skin reaction), H318 (Causes serious eye damage), H319 (Causes serious eye irritation), H335 (May cause respiratory irritation) |
| Precautionary Statements |
P261 (Avoid breathing dust/fume/gas/mist/vapors/spray), P280 (Wear protective gloves/protective clothing/eye protection/face protection), P302+P352 (IF ON SKIN: Wash with plenty of water), P305+P351+P338 (IF IN EYES: Rinse cautiously with water) |
| Oral LD50 (Rat) |
~5,000-10,000 mg/kg |
| Dermal LD50 (Rabbit) |
> 2,000 mg/kg |
| Skin Irritation |
Irritant |
| Eye Irritation |
Serious eye damage (H318) |
| Skin Sensitization |
Positive (allergic contact dermatitis) |
| Mutagenicity |
Negative |
| Carcinogenicity |
Not classified |
| Reproductive Toxicity |
Not classified |
| Target Organs |
Skin, eyes, respiratory system |
| Occupational Exposure Limit (TWA) |
Not established |
SECTION 10: ECOTOXICOLOGY AND ENVIRONMENTAL BEHAVIOR
| Parameter |
Value / Description |
| Fish Toxicity (LC50, 96 hours) |
~100-500 mg/L |
| Daphnia Toxicity (EC50, 48 hours) |
~100-500 mg/L |
| Algae Toxicity (EC50, 72 hours) |
~100-500 mg/L |
| Biodegradability |
Readily biodegradable (OECD 301) |
| Bioaccumulation |
Low (LogP ~0.19) |
| Hydrolysis |
Hydrolyzes to methacrylic acid and ethylene glycol |
| Water Hazard Class (WGK Germany) |
WGK 1 (slight hazard to water) |
Ecotoxicological Summary: HEMA is readily biodegradable and has low bioaccumulation potential. It shows moderate aquatic toxicity.
SECTION 11: SAFETY MEASURES AND PERSONAL PROTECTIVE EQUIPMENT
| Parameter |
Information |
| Respiratory Protection |
Organic vapor cartridge (at high concentrations) or SCBA |
| Gloves |
Chemically resistant (nitrile, butyl rubber, Viton) |
| Eye Protection |
Chemical safety goggles + face shield |
| Body Protection |
Chemical-resistant apron, full protective clothing |
| Ventilation |
Local exhaust ventilation and general ventilation |
| Special Precautions |
Avoid sunlight; protect from heat and ignition sources |
| Engineering Controls |
Closed systems; inert atmosphere (N₂) when possible |
SECTION 12: STORAGE INFORMATION
| Parameter |
Information |
| Storage Conditions |
Cool, dry, well-ventilated area |
| Temperature |
15–25°C (store under inert atmosphere) |
| Container |
Tightly closed, dark, plastic (HDPE) drums, IBC tanks, ISO tanks |
| Special Requirements |
Must contain inhibitor (MEHQ); avoid extreme temperatures |
| Water Contamination |
Avoid water ingress (accelerates polymerization) |
| Sunlight Protection |
Protect from direct sunlight; use insulated covers for outdoor storage |
| Shelf Life |
6 months (under recommended conditions) |
| Packaging |
200 kg plastic drum, IBC tank, ISO tank |
SECTION 13: TRANSPORT INFORMATION
| Parameter |
Information |
| UN Number |
Not regulated (not classified as dangerous goods) |
| Hazard Class |
Not applicable |
| Packing Group |
Not applicable |
| Proper Shipping Name |
2-Hydroxyethyl Methacrylate (HEMA) |
| ADR/RID |
Not regulated |
| IMDG Code |
Not regulated |
| IATA (Air) |
Not regulated |
| Marine Pollutant |
No |
| Transport Notes |
Avoid collision; prevent leakage; wash spill with water |
SECTION 14: FIRE-FIGHTING MEASURES
| Parameter |
Information |
| Fire Hazard |
Combustible liquid (flash point ~97°C) |
| Extinguishing Media |
Water fog, foam, CO₂, dry chemical |
| Special Hazards |
When heated, releases CO, CO₂, and irritant vapors |
| Decomposition Products |
CO, CO₂, methacrylic acid vapors |
| Protective Equipment |
Self-contained breathing apparatus (SCBA), full protective clothing |
| Explosion Risk |
Vapor/air mixtures may be explosive at high temperatures |
| Water Use |
Prevent fire-fighting water from entering the environment |
SECTION 15: ACCIDENTAL RELEASE AND CLEANUP
| Parameter |
Information |
| Personal Protection |
Gloves, safety goggles, face shield, protective clothing |
| Ventilation |
Increase ventilation; evacuate area |
| Control |
Stop source; prevent vapor spread |
| Cleanup Methods |
Absorb with inert absorbent material; collect in sealed containers |
| Environmental Precautions |
Prevent entry into drains and water bodies |
| Waste Disposal |
According to local regulations; incineration (hazardous waste) |
SECTION 16: FIRST AID MEASURES
| Exposure Route |
Action |
| Inhalation |
Move to fresh air. Administer oxygen if breathing difficulty. Seek medical attention. |
| Skin Contact |
Remove contaminated clothing. Wash with soap and plenty of water for at least 15 minutes. Seek medical attention. |
| Eye Contact |
Rinse with plenty of water for at least 15 minutes. Seek immediate medical attention. |
| Ingestion |
Do NOT induce vomiting. Drink plenty of water. Seek immediate medical attention. |
SECTION 17: REGULATORY INFORMATION
| Region / Authority |
Status |
| EU REACH |
Registered |
| Turkey KKDİK |
Registration required |
| USA TSCA |
Listed |
| USA FDA |
Approved for food contact (21 CFR 177.1010) |
| EU Food Contact |
Permitted under specific conditions |
| EINECS |
212-782-2 |
| RTECS |
OZ4725000 |
| WGK (Germany) |
1 (slight hazard to water) |
SECTION 18: SUMMARY AND CRITICAL WARNINGS
Product Summary
| Parameter |
Value |
| Product |
2-Hydroxyethyl Methacrylate (HEMA) |
| CAS |
868-77-9 |
| Appearance |
Colorless liquid |
| Density |
~1.07 g/cm³ |
| Boiling Point |
~250°C (decomposes) |
| Water Solubility |
Soluble (miscible) |
| Flash Point |
~97°C |
| Key Industries |
Coatings, adhesives, textiles, paper, medical, dental |
CRITICAL WARNINGS
-
Hydrophilic Monomer: HEMA is a hydrophilic methacrylate monomer containing both a methacrylate group (polymerizable) and a hydroxyl group (functionalizable). This dual functionality makes it highly versatile.
-
Polymerization Risk: Readily polymerizes; always contains inhibitor (200 ppm MEHQ). Keep away from heat and light. Do not store without inhibitor.
-
Water Sensitivity: Water ingress can accelerate polymerization. Avoid water contamination during storage and handling.
-
Storage Temperature: Shelf life is 6 months under normal temperature (15–25°C). Store in cool, dark, well-ventilated areas.
-
Skin and Eye Irritant: Causes serious eye damage (H318) and skin irritation (H315). May cause allergic skin reactions (H317). Appropriate PPE required.
-
Skin Sensitizer: HEMA is a known allergen and sensitizer. Repeated exposure may cause allergic contact dermatitis.
-
Low Volatility: Low vapor pressure and high boiling point make it a low-volatility monomer.
-
Sunlight Protection: Protect from direct sunlight; use insulated covers for outdoor storage.
-
Transport: Avoid collision; wash spills with water.
-
Regulatory Status: Registered under REACH. FDA-approved for food contact (21 CFR 177.1010).
IMPORTANT DISCLAIMER: This Technical Data Sheet (TDS) is for informational purposes only and is based on available technical data. The user is solely responsible for determining the product's suitability for their specific application and for complying with all applicable local, national, and international regulations. HEMA readily polymerizes and is a known skin sensitizer! For complete safety, storage, handling, transportation, disposal, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are responsible for testing the product in their own processes and applications. All local, national, and international regulations must be followed when working with HEMA.
