Di-butyl itaconate

Interestingly, itaconate esters can be polymerized at a moderate rate to yield high-molecular-weight polymers in spite of their possession of two bulky substituents. Kamachi et al. observed a 5-line ESR spectrum with small shoulders as shown in Fig. 61 when di-butyl itaconate (DBI) was photopolymerized in bulk with BP at low temperature. They computer-simulated a similar spectrum by assuming the hyperfine splitting constant to be 14.1 G for two P-protons and 10.1 G for another two P-protons, and concluded that the observed spectrum can be attributed to... 

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