Efficient Pathway for Preparing Hollow Particles: Site-Specific Crosslinking of Spherical Polymer Particles with Photoresponsive Groups That Play a Dual Role in Shell Crosslinking and Core Shielding

Site-specific a posteriori photocrosslinking of homogeneous spherical polymer particles and subsequent removal of the particle corethe self-templating strategyhas been developed as an efficient pathway for hollow particle formation. In this approach, homogeneous polymer particles containing linear polymers bearing post-crosslinkable side-chain groups are first synthesized, and the photoinduced crosslinking occurred only at the shell region in the homogeneous polymer particles. Our fundamental studies clarified that the remaining non-crosslinked photoresponsive groups in the shell region played a crucial role in shielding the core region from photoirradiation. The shell-selective crosslinking was successfully applied to hollow polymer particle formation by core removal. This facile route to polymeric hollow particle formation via a self-templating strategy has great potential to be used as an alternative because the route has high mass productivity and high simplicity as a result of the non-use of additional sacrificial template particles and highly toxic solvents.