I am interested in using a UV or VIS light source to rapidly cure certain points on a polymer with high throughput. I have the ability to use light of the following power:
363 - 400 nm: 40 W/mm^2
400 - 420 nm: 180 W/mm^2
420 - 700 nm: 180 W/mm^2
Are there any polymers that can be cured with this light on the timescale of milliseconds (ideal) to seconds? If not, what is the primary limitation? Note that the reaction doesn't need to be complete in that timescale, just that it is initiated and will go completion after that level of exposure.
The only other requirement is that the polymer on curing should be optically clear. It is okay if other processes (such as heat) can be applied after.
In my view most preformed polymers e.g. polystyrene will not be crosslinked (cured) by these settings. One of the "laws of photochemistry" is that in order for photochemical reactions to occur light but be absorbed by the materials of interest. If you look up UV/vis absorption data for common polymers like polystyrene they absorb weakly or not at all in the range 363-700 nm range. Therefore photochemical "curing" will take place slowly or not at all.
Now, if you wanted to do UV photopolymerization of liquid prepolymers using photoinitiators you would have lots of options. Consider these papers as good starting points for fast UV cure formulations
DOI: 10.1021/cm2015093
DOI: 10.1021/am503563q
To be sure you should started with photocalorimetrical analysis in order to evaluate kinetics of the reaction. Photopolymerization is non trivial method and depends on many things. If you want to cure your material rapidly you should focus on the concentration of reactive groups (like eg. methacrylic). Generally, with increasing concentration of reactive groups reaction speed also increases. But I would rather start with photo-DSC.
Commercially available resins which can be cured by UV are monomolecular substances or oligomers solved in an reactive diluent. But you can synthesize polymers able to be cured by UV from hydroxy functional polymers like the copolymer of styrene and allylalcohol or derivatives of starch and cellulose. You can also use Acrylate Desmophen (there are many types) as OH functional component. You must react them with isocyanatoethyl methacrylate, which is commercially available.
O=C=N-CH2-CH2-O-CO-C(CH3)=CH2
The isocyanate group forms an urethane with the hydroxy groups of the polymer. Such resins can be solved in a reactive diluent like TMP-trimethycrylate. With an appropriate photoinitiator like Irgacure 819 and a H-donor like mercaptanes or N,N-dialkyl anilines these systems can be cured with blue light or near UV.
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