title: Nonaqueous Dispersion Formed by an Emulsion Solvent Evaporation Method Using Block-Random Copolymer Surfactant Synthesized by RAFT Polymerization.
abstract: As surfactants for preparation of nonaqueous microcapsule dispersions by the emulsion solvent evaporation method, three copolymers composed of stearyl methacrylate (SMA) and glycidyl methacrylate (GMA) with different monomer sequences (i.e., random, block, and block-random) were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Despite having the same comonomer composition, the copolymers exhibited different functionality as surfactants for creating emulsions with respective dispersed and continuous phases consisting of methanol and isoparaffin solvent. The optimal monomer sequence for the surfactant was determined based on the droplet sizes and the stabilities of the emulsions created using these copolymers. The block-random copolymer led to an emulsion with better stability than obtained using the random copolymer and a smaller droplet size than achieved with the block copolymer. Modification of the epoxy group of the GMA unit by diethanolamine (DEA) further decreased the droplet size, leading to higher stability of the emulsion. The DEA-modified block-random copolymer gave rise to nonaqueous microcapsule dispersions after evaporation of methanol from the emulsions containing colored dyes in their dispersed phases. These dispersions exhibited high stability, and the particle sizes were small enough for application to the inkjet printing process.
authors.affiliation: Graduate School of Science and Engineering, Yamagata University , 4-3-16, Jonan, Yonezawa 992-8510, Japan.|RISO KAGAKU CORPORATION, 2-8-1 Gakuen-minami, Tsukuba-shi, Ibaraki 305-0818, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Ezaki
authors.affiliation: RISO KAGAKU CORPORATION, 2-8-1 Gakuen-minami, Tsukuba-shi, Ibaraki 305-0818, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Watanabe
authors.affiliation: Graduate School of Science and Engineering, Yamagata University , 4-3-16, Jonan, Yonezawa 992-8510, Japan.
authors.forename: Hideharu
authors.initials: H
authors.lastname: Mori