Overview
Butyl acrylate is an ester of acrylic acid and n-butanol, serving as a fundamental building block in polymer chemistry. As a liquid monomer with low glass transition temperature (Tg ≈ -54°C), it imparts flexibility to acrylic polymers. Industrial production typically involves esterification of acrylic acid with butanol or transesterification routes. The global market for butyl acrylate exceeds 2 million tons annually, driven by demand from Asia-Pacific coating manufacturers. Major producers include BASF, Dow Chemical, and Arkema, with production facilities strategically located near acrylic acid feedstock sources.
Physical and Chemical Properties
Butyl acrylate's chemical structure (CH2=CHCOO(CH2)3CH3) enables radical polymerization through its vinyl group. It exhibits characteristic acrylic ester properties: low surface tension (25 dynes/cm at 20°C), refractive index of 1.418, and flash point of 39°C (closed cup). The vapor pressure is 4 mmHg at 20°C, requiring careful vapor management during handling. Polymerization inhibitors like hydroquinone monomethyl ether (MEHQ) are added to prevent premature polymerization during storage. Technical grade typically contains 99% purity with ≤0.1% water content. The azeotrope with water (71°C, 28% water) is relevant for purification processes.
Main Applications
Approximately 60% of butyl acrylate consumption goes into acrylic emulsion polymers for water-based paints and coatings. These formulations provide weatherability and UV resistance for architectural applications. In pressure-sensitive adhesives, butyl acrylate copolymerizes with acrylic acid to achieve optimal tack-peel balance. The textile industry utilizes butyl acrylate in fabric finishes (15% of market) to create flexible coatings. Emerging applications include 3D printing resins and thermoplastic elastomers, where its low Tg enables flexible end products. Recent innovations focus on sustainable variants using bio-based butanol feedstocks.
Safety and Storage
As a Category 3 flammable liquid (GHS classification), butyl acrylate requires storage in grounded, non-reactive containers (stainless steel or polyethylene-lined). NFPA ratings include Health 2, Flammability 2, Reactivity 2. Proper ventilation should maintain vapor concentrations below 10 ppm (OSHA PEL). Emergency measures include alcohol-resistant foam for firefighting and activated carbon for spill absorption. Polymerization risk increases above 50°C - storage temperatures should not exceed 30°C. Transportation requires UN number 2348 (Packing Group III) with inhibitor verification for extended shipments.
B2B Procurement Guide
Industrial buyers should specify technical (≥99%) or purified (≥99.5%) grades depending on application needs. Key quality indicators include acid value (<0.5 mg KOH/g), color (APHA <20), and inhibitor content (MEHQ 10-20 ppm). Bulk purchases (ISO tank containers) typically offer 10-15% cost savings versus drum quantities. Supply chain considerations include regional production capacity (China accounts for 40% of global output) and logistics requirements for temperature-controlled transport. Contracts should address force majeure clauses given feedstock (propylene) price volatility. Third-party lab certificates of analysis are recommended for spot purchases.