The photo polymerization has characteristic as well as free radical polymerization which the first step is photoinitiation. Photoinitiator is a catalyst used to photo polymerization with absorption of light to produce reactive species. In the photo polymerization there is propagation chain growth and termination chain growth (include chain transfer and disproportionation). Photo initiators have two types to generate reactive species. The first type is very reactive to break double bonds after getting photon. Thus, the second type form excited tripled state for hydrogen absorption and electron transfer. In this experiment we used the first type of photo initiators that is IRGACURE 2959 with using range of wavelengths of UV about 300-400 nm (the structure can be seen figure1).
