High Performance Reactive UV Absorber Monomer, CAS 16432-81-8 | 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl acrylate

CAS 16432-81-8, Chemical Name: 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl acrylate. It is a benzoylphenol-based reactive UV absorber monomer. Its molecular structure contains both the hydroxybenzophenone UV chromophore and acrylic reactive double bonds. Unlike conventional small-molecule UV absorbers which are only physically blended into formulations, this product participates in photocuring crosslinking reactions and is covalently bonded into the 3D resin network. It fundamentally addresses common industry drawbacks of traditional UV absorbers such as migration, blooming, precipitation and poor extraction resistance, making it a functional monomer dedicated to high-performance weather-resistant photocuring systems.

Molecular Formula: C₁₈H₁₆O₅, Molecular Weight: 312.32. Appearance: Pale yellow viscous liquid or low-melting solid. UV absorption range: 280–360 nm. It offers excellent absorption for UV-A and UV-B bands, effectively scavenging free radicals generated under UV excitation and suppressing chain scission degradation of resin molecules. Industrial grade purity ≥98%, with low impurities and superior batch-to-batch stability. It exhibits good compatibility with acrylate monomers and oligomers, does not easily cause turbidity, and has minimal impact on coating transmittance.

Key Product Advantages

1.Reactive bonding, non-migrating and non-precipitating The acrylic double bond in the molecule enables copolymerization with resins and monomers in the system during UV curing, locking the structure inside the cured film via chemical bonds. It will not migrate to the coating surface under solvent or moisture exposure to cause blooming and hazing; it also resists extraction by solvent wiping or rain immersion, maintaining long-term anti-yellowing performance.

2.Broad-spectrum UV absorption, anti-aging and anti-yellowing The benzophenone parent structure efficiently absorbs ultraviolet light and converts light energy into harmless thermal energy, inhibiting photo-oxidative degradation. It significantly delays coating yellowing, chalking and cracking, greatly improving the long-term stability of outdoor articles and optical coatings.

3.Excellent formulation compatibility, minor interference on curing Miscible with most epoxy acrylates, polyurethane acrylates, polyester acrylates and reactive diluents. Within the recommended dosage range, it will not markedly inhibit photoinitiation, nor degrade fundamental mechanical properties such as coating hardness and adhesion, and preserves coating transparency, suitable for clear coatings.

4.Low volatility and low odor Compared with small-molecule benzophenone UV absorbers, it has lower volatility and less odor emission during curing. Suitable for low-VOC, eco-friendly photocuring formulations and meets strict environmental requirements for electronics and optical materials.

Typical Application Scenarios

*Outdoor photocuring topcoats: Clear protective varnishes for building materials, metals and plastics used outdoors to improve weather resistance, gloss retention and color retention

*Optical coatings: Hard coats for PET/PC films, optical protective films, UV coatings for lenses, to prevent substrate aging and yellowing

*3D printing photoresins: SLA/DLP printed parts to mitigate yellowing of finished products during long-term storage

*Electronic protective inks and adhesives: UV inks and encapsulation protective adhesives for PCB and flexible electronics with resistance to environmental aging

*Packaging and flexible film inks: Lightfast printing inks to enhance UV resistance of outdoor labels and decorative films

*Wood photocuring coatings: Outdoor UV clear varnishes for wood to delay aging and cracking of wood coatings

Recommended Usage

Recommended loading level: 1–5% of total formulation, adjustable according to required weather resistance grade. It can be used synergistically with photoinitiators and hindered amine light stabilizers (HALS) to further boost weathering performance. During formulation development, curing speed, coating transparency and accelerated aging tests are recommended to optimize the dosage.

Summary

CAS 16432-81-8 is a reactive UV absorber monomer that overcomes the inherent drawback of easy migration of conventional additive-type UV absorbers. It combines UV protection performance with photocuring reactivity. Suitable for high-end photocuring coatings, inks, photoresins, optical films and other fields. It is the preferred functional raw material for formulations requiring long-term weather resistance, high transparency and non-bleeding properties.