Buy Polyurethane Acrylate Oligomer Manufacturer & Factory

Aromatic polyurethane acrylates (typically synthesized with TDI or MDI) contain benzene rings directly linked to urethane nitrogen atoms. Exposure to UV radiation and atmospheric oxygen triggers photochemical degradation of these aromatic rings into quinoid chromophores, leading to visible yellowing (ΔYI > 5.0). Aliphatic PUAs use cycloaliphatic or linear aliphatic isocyanates (such as IPDI, H12MDI, or HDI), which lack conjugate-stabilized aromatic rings. This eliminates the photochemical mechanism that forms quinoid structures, keeping cured films transparent (ΔYI < 0.5) under long-term outdoor sunlight and QUV exposure.

Atmospheric molecular oxygen rapidly scavenges free radicals generated by photoinitiators, forming stable peroxy radicals that slow or stop polymerization, leaving a tacky film surface. To resolve this without nitrogen inerting, we recommend: (1) Blending 10–25% amino acrylate oligomers or active amine synergists into the resin system. These amines provide abstractable alpha-hydrogens that convert peroxy radicals back into active carbon-centered radicals while consuming oxygen; (2) Utilizing higher-functionality urethane acrylates (tetra-, hexa-, or hyperbranched grades) to rapidly build crosslink density before oxygen can diffuse into the film; (3) Optimizing the photoinitiator system with long-wavelength Type I cleavage initiators (e.g., TPO, 819) paired with surface-active Type II initiators or co-initiators.

Pure polyurethane acrylate oligomers often have viscosities between 10,000 and 150,000 mPa·s at 25°C due to hydrogen bonding across urethane linkages. To adjust viscosity for roller or spray applications while maintaining 100% solids, formulators use monofunctional and difunctional reactive acrylate diluents: (1) For high flexibility and low shrinkage: IBOA (isobornyl acrylate) or ACMO (acryloyl morpholine); (2) For fast cure and balanced crosslink density: TPGDA (tripropylene glycol diacrylate) or DPGDA; (3) For enhanced hardness: HDDA (1,6-hexanediol diacrylate). Alternatively, Ever Ray synthesizes low-viscosity modified polyurethane acrylates that integrate internal plasticizing chains, cutting base viscosity down to 3,000–8,000 mPa·s at 25°C without diluents.

Waterborne polyurethane acrylate (WPUA) dispersions contain high-molecular-weight PUA polymer particles dispersed in water with internal ionic groups (such as DMPA carboxylates). They require a flash-off thermal heating step (50–70°C for 2–5 minutes) to evaporate water before UV exposure. Once dried and cured, WPUA delivers very thin dry film builds (5–15 μm), a natural open-grain look on luxury wood, and low odor, making it suitable for automotive interior spray lines. 100% solid PUAs contain no water or volatile carriers; they cure instantly upon UV radiation without ovens, resulting in zero volatile emissions, higher line speeds, and thick single-pass builds (20–100 μm).

We provide prospective commercial clients and formulators with 500g to 2kg trial samples shipped via international express (air couriers) accompanied by: (1) A Certificate of Analysis (COA) containing batch-specific viscosity, acid value, color number, and non-volatile content; (2) Detailed Technical Data Sheets (TDS) with starting formulation recommendations, photoinitiator suggestions, and lamp energy cure windows; (3) Regional GHS-compliant Safety Data Sheets (SDS); (4) Direct consultation with our R&D synthesis team for custom backbone modifications if specific substrate adhesion or flexibility goals are not met.