Preparation of poly(methyl methacrylate) microspheres via photopolymerization initiated by LED light source

Poly(methyl methacrylate) (PMMA) microspheres were synthesized through visible light–induced photopolymerization of methyl methacrylate (MMA). 2,4,6-Trimethylbenzoyldipenylphosphine oxide (TPO), polyvinylpyrrolidone (PVP), and light-emitting diodes (LEDs) were used as the photoinitiator, stabilizer, and light source, respectively. No other additive was involved. The effect of LEDs, TPO, and PVP was discussed. Results showed that PMMA microspheres with the size of 0.5–0.8 μm could be obtained when LED@385 nm was the light source, and the content of TPO and PVP was 2 wt% and 30 wt% of MMA. Moreover, the possible formation pathway of PMMA microspheres was proposed based on the investigation of reaction time and addition method of PVP. Graphical abstract