Butyl Acrylate, Butyl Acrylate Monomer, n-Butyl Acrylate, n-Butyl Propenoate, BA, 141-32-2

BUTYL ACRYLATE (BA)

Butyl Acrylate / n-Butyl Acrylate / Butyl Acrylate Monomer / n-Butyl Propenoate / BA
CAS Number: 141-32-2
EC Number: 205-480-7
UN Number: 2348

SECTION 1: PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

Butyl Acrylate is a monofunctional acrylate monomer belonging to the acrylate ester family. It is produced by the esterification of acrylic acid with n-butanol. This clear, colorless liquid with a characteristic sharp, pungent ester odor serves as a versatile comonomer in the production of various polymers and copolymers. Its unique molecular structure contains a reactive vinyl group and a flexible butyl side chain, which impart excellent properties such as low glass transition temperature (Tg), flexibility, weatherability, and water resistance to final polymer products. The monomer is stabilized with an inhibitor to prevent premature polymerization during storage and transport.

SECTION 2: SYNONYMS AND OTHER NAMES

SECTION 3: CHEMICAL STRUCTURE

3.1. Molecular Structure

Butyl Acrylate consists of a reactive vinyl group (-CH=CH₂) esterified with a butyl group (-C₄H₉). The molecule contains a carbon-carbon double bond that enables polymerization.

Structural Formula:

        O
        ||
   CH₂ = CH - C - O - CH₂ - CH₂ - CH₂ - CH₃

Simplified Representation:
CH₂=CH-COO-C₄H₉

3.2. Molecular Formula

C₇H₁₂O₂

3.3. Molecular Weight

128.17 g/mol

3.4. Key Structural Features

SECTION 4: SPECIFICATIONS (SALES SPECIFICATION)

The sales specification for Butyl Acrylate defines the essential quality parameters for commercial acceptance. Purity, determined by gas chromatography with flame ionization detection (GC-FID), is the most critical parameter with a minimum requirement of 99.5%. Acid content, expressed as acrylic acid, must not exceed 0.01%, ensuring minimal corrosive impurities and optimal polymerization performance. Water content is tightly controlled at a maximum of 0.05% using the Karl Fischer method, as moisture can adversely affect polymerization reactions and product stability. Color, measured in APHA units, must not exceed 10, indicating a high-purity, water-white product. Inhibitor content (MEHQ - hydroquinone monomethyl ether) is maintained at 15 ± 5 ppm to provide adequate storage stability while allowing efficient polymerization initiation. The product should appear as a clear, colorless liquid with no visible suspended matter or turbidity.

SECTION 5: PHYSICAL AND CHEMICAL PROPERTIES

SECTION 6: SOLUBILITY PROFILE

SECTION 7: COPOLYMERIZATION PROPERTIES

Butyl Acrylate readily copolymerizes with a wide range of monomers including methacrylates, styrene, vinyl acetate, acrylonitrile, and maleic anhydride, making it one of the most versatile comonomers in polymer chemistry. The high reactivity of the acrylate double bond allows efficient polymerization through free radical, emulsion, and solution polymerization techniques.

Reactive Double Bond:

CH₂=CH-COO-C₄H₉

Compatible Comonomers:

• Methacrylates (Methyl Methacrylate, Ethyl Methacrylate, Butyl Methacrylate)

• Styrene and Styrene Derivatives

• Vinyl Acetate

• Acrylonitrile

• Maleic Anhydride

• Hydroxyethyl Acrylate and other functional acrylates

• Acrylic Acid and other acid monomers

Properties Imparted to Polymers:

Typical Reactivity Ratios (r values):

Polymerization Methods:

SECTION 8: APPLICATIONS AND INDUSTRIAL USES

Butyl Acrylate is a critical comonomer that provides flexibility, adhesion, and low-temperature performance to polymer chains due to its low Tg (poly-BA Tg ~ -55°C). The long butyl side chain acts as an internal plasticizer, imparting excellent performance properties to final products.

8.1. Paints and Coatings

8.2. Adhesives

8.3. Textile and Leather

8.4. Paper and Pulp Industry

8.5. Plastics, Putties, and Sealants

8.6. Other Applications

SECTION 9: SAFETY AND HEALTH INFORMATION (GHS CLASSIFICATION)

Signal Word: DANGER

Hazard Statements (H-Codes):

Precautionary Statements (P-Codes):

SECTION 10: HEALTH EFFECTS

SECTION 11: FIRST AID MEASURES

SECTION 12: TOXICOLOGICAL PROFILE

SECTION 13: OCCUPATIONAL EXPOSURE LIMITS

SECTION 14: STABILITY AND INHIBITOR

Butyl Acrylate is prone to spontaneous polymerization which can occur due to heat, light, oxygen depletion, and certain contaminants. The commercial product is stabilized with 15 ± 5 ppm MEHQ (Hydroquinone Monomethyl Ether) as a polymerization inhibitor. The inhibitor requires the presence of oxygen to remain effective; therefore, the product should be stored in tanks with adequate air headspace and SHOULD NOT BE BLANKETED WITH NITROGEN. Oxygen depletion in the vapor space can deactivate the inhibitor, leading to uncontrolled polymerization which can be highly exothermic and hazardous. Inhibitor levels should be periodically monitored during long-term storage, and additional inhibitor may be added if levels drop below specification.

Polymerization Risk Factors:

SECTION 15: STORAGE CONDITIONS

SECTION 16: FIRE-FIGHTING MEASURES

SECTION 17: ACCIDENTAL RELEASE MEASURES

SECTION 18: TRANSPORT INFORMATION

SECTION 19: REGULATORY INFORMATION

SECTION 20: ENVIRONMENTAL INFORMATION

SECTION 21: OTHER NAMES AND DATABASE IDENTIFIERS

SECTION 22: QUICK REFERENCE TABLE

SECTION 23: CRITICAL NOTICES AND BEST PRACTICES

CRITICAL NOTICES:

1. Spontaneous Polymerization Risk: Butyl Acrylate readily polymerizes and can undergo spontaneous, exothermic polymerization if exposed to high temperatures (above 30°C), certain contaminants (metals, acids, bases, peroxides), or if the inhibitor becomes depleted. The MEHQ inhibitor requires oxygen to function; therefore, DO NOT BLANKET WITH NITROGEN. Maintain adequate air headspace in storage tanks and ensure proper ventilation.

2. Skin Sensitization: Butyl Acrylate is classified as a skin sensitizer (Category 1). Repeated or prolonged skin contact can cause allergic contact dermatitis, which may be irreversible in sensitized individuals. Use appropriate protective gloves (nitrile, neoprene) and avoid skin contact. If skin contact occurs, immediately wash with soap and water and remove contaminated clothing.

3. Flammability: With a flash point of 29°C, Butyl Acrylate is a flammable liquid. Vapors are heavier than air and can travel to ignition sources, causing flashback. Use explosion-proof electrical equipment, ensure proper grounding and bonding, and keep away from open flames, sparks, and heat sources. Store in a well-ventilated area away from oxidizers and ignition sources.

4. Inhibitor Management: Regularly monitor MEHQ levels during long-term storage. If inhibitor levels drop below 10 ppm, additional inhibitor may be required to maintain stability. Consult inhibitor suppliers for proper concentration guidelines.

5. Shelf Life: Under proper storage conditions (below 30°C, adequate air headspace, protected from light and contamination), the shelf life is 6-12 months from the date of manufacture. Store with adequate air headspace (minimum 10-15% headspace) to ensure sufficient oxygen supply for the inhibitor.

6. Emergency Response: In case of spills, eliminate all ignition sources, increase ventilation, and contain the spill using inert absorbent materials. For fires, use alcohol-resistant foam, CO₂, dry chemical, or water spray. Wear self-contained breathing apparatus and full protective clothing. Evacuate unnecessary personnel from the area.

LEGAL DISCLAIMER:

This Technical Data Sheet (TDS) is for informational purposes only. The information provided is based on available data and is believed to be accurate. However, the user is solely responsible for determining the suitability of the product for their specific applications and for complying with all applicable regulations and safety requirements. For complete safety, handling, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are obligated to test the product in their own processes and applications. All local, national, and international regulations must be followed when working with Butyl Acrylate. This document does not substitute professional or medical advice.