Products Description
SR-2345 is a low viscosity isocyanate functional unsaturated acrylate resin, with Hexaphenylhexamethylene diisocyanate-based dual-cure coating for light and weather resistance
main Features and Benefits
-minimal yellowing
-easy to mix with other photoinitiators
Chemistry Structure
acrylic isocyanate
typical Features
Appearance | Low viscosity liquid |
Viscosity@23℃(73 °F ) (DIN EN ISO 3219) (cut Cut rate D6,700s–¹) |
~ 1.0 – 1.4 mPa s |
NCO content (DIN EN ISO 11909) |
~14.5-15.5% |
Platinum Cobalt (Hazen) Color Number (ISO 6271) |
≤ 150 |
NCO equivalent weight (contains 1 mole of active isocyanic acid Salt® SR-2345 quantity) |
289.7 – 271.0 |
Density @ 50°C (122°F ) (DIN 51757, process 4.3) |
~ 1.133 g/cm³ |
Solubility , dilution tolerance
Solvents (except aliphatic hydrocarbons) and reactive thinners common in the coating industry can be used , such as low viscosity acrylates and vinyl ethers. NOTE: Viscosity may increase due to ingredients reacting with isocyanates, such as water and alcohols.
Compatibility
Usable esters such as butyl acetate, ketones such as methyl ethyl ketone, ethylene glycol Aromatic hydrocarbons such as alcohol ether acetate and xylene are thinned. These typical values should not be interpreted as specifications.
apply
SR-2345 is an aliphatic acrylate with isocyanate function, its reaction It is recommended as an isocyanate and acrylate component for dual cure applications.
It is therefore often used in combination with hydroxyl-containing resins or other radiation-curable resins , mainly in double-pack formulations.
Dual cure application of SR-2345 can be weather resistance and scratch resistance coating . For pigmented coatings that cannot be cured by UV light, thermal pre-curing is required. Subsequent UV curing produces a coating with excellent weather and scratch resistance.
SR-2345, a low tack resin, can also be used as the only tack Binder. After exposure to UV radiation, the isocyanate groups react with the ambient environment and the inherent moisture of the substrate to form a blister-free coating. Most notably, this one-pack application is suitable for porous substrates and substrates with poor adhesion properties.
Polyisocyanate component and polyol (isocyanate: OH = 1) The stoichiometric reaction is calculated from the isocyanate content:
0.075×[OH value]×[volatile components of non-polyols] /[isocyanate]
Some manufacturers express the content of hydroxyl groups as OH %, in this case, the formula for the stoichiometric reaction becomes:
0.075[OH%]x[polyol non-volatile fraction]/17x[ NCO]
processing
SR-2345 can be further diluted for processing. Suitable for low volatility monomers such as monofunctional, difunctional or trifunctional acrylates. Monomers are incorporated into the film, thereby affecting its properties.
Monofunctional monomers increase flexibility; difunctional monomers contribute to hardness and flexibility The effect of trifunctional monomer is not big, but the hardness of cured film is increased by trifunctional monomer.
Inert solvents can be used if there is sufficient flash zone. However, these solvents must be completely removed from the film before exposure to radiation.
SR-2345 is used in combination with hydroxyl functional resins, such as hydroxyl acrylic resin, hydroxyl polyester, hydroxyl polyether), aliphatic polyol or hydroxyl functional unsaturated acrylic resin.