2-hydroxypropyl acrylate

2-Hydroxypropyl acrylate (CAS 2918-23-2), commonly abbreviated as HPA, is a reactive hydroxyl-functional monomer used in UV-curable and free-radical polymerization systems. The hydroxyl group provides a reactive site for crosslinking, enabling formulators to tune hardness, flexibility, and adhesion in cured polymer networks for industrial applications.

In UV-curable coatings and inks, HPA is incorporated as a reactive diluent to reduce viscosity while contributing to the final crosslinked structure, a critical balance for high-speed lines. Adhesive and sealant manufacturers use it to introduce hydroxyl functionality into acrylic polymer backbones, improving substrate adhesion and cohesive strength in various formulations.

In two-component polyurethane systems, the hydroxyl group reacts directly with isocyanates, making HPA a functional monomer for structural adhesives and elastomeric coatings. Polymer producers also use it to introduce pendant hydroxyl groups for post-cure modification or grafting in specialty resin development and other advanced chemical processes.

2-Hydroxypropyl acrylate is supplied as a clear liquid, typically with a polymerization inhibitor added for storage stability. Technical grade is the standard commercial offering. Purity specifications are commonly at 96% or higher. Bulk supply in drums and IBC containers is standard; inhibitor type and concentration are often specified by buyers to match requirements.