Effect of second monomer and initiator type, mixing method, and stabilizer content on the shape of the particles produced by seeded dispersion polymerization in the presence of saturated hydrocarbon droplets

Fabrication of unique cage-like polystyrene particles having lots of dents on the surface via unstable seeded dispersion polymerization

“…The question became more penetrating when we knew that in previous works [10][11][12][13], production of polyhedral particles via this technique had been reported. In these works, PS seed particles were prepared via dispersion polymerization of styrene initiated by AIBN and stabilized by PVP, whereas in the present study, BPO and PVA-80 % were employed as initiator and stabilizer, respectively.…”

“…Lower viscosity, which can be achieved by diffusion of high amount of hydrocarbon and PEHMA phase into the PS phase results in increasing the rates of hydrocarbon/PEHMA domains coalescence and Ostwald ripening between the domains, and therefore, formation of more nonspherical shapes (e.g., disk-like or ellipsoidal) [10][11][12][13]. As it was mentioned, previous studies reported the production of polyhedral particles when hexadecane was employed as the hydrocarbon; however; Fig.…”

“…Functionality of such particles depends on various parameters (e.g., composition, polarity, size, size distribution, and so forth) among which, shape is considered as an important one. Several studies have been reported regarding the production of polymer particles with a variety of shapes such as "egg-like" [1], "confetti-like" [2], "raspberry-like" [3][4][5][6], "snowman-like" [2,7], "rugby-ball-like" [8], golf-ball-like [9], disk-like [10][11][12][13], red blood corpuscle-like [14], and so forth. We have also reported the fabrication of particles with novel almond shell-like shape via dual-seeded dispersion polymerization (SDP) [15,16] as well as half-shell polystyrene (PS) particles with controllable surface area using micromolding-polymerization [17].…”

Dual-seeded dispersion polymerization: formation mechanism of novel and unique ring-like and almond-shell-like polystyrene particles

“…SDP in the presence of an organic solvent is an exceptional method which has been introduced by Okubo et al They prepared polyhedral and disk-like particles by employing this technique [14][15][16]. We also examined the effect of various polymerization conditions on the shape and stability of the obtained particles via this approach [20][21][22]. The results showed that most of the particles prepared via this technique own symmetric shapes, whereas asymmetric structures are preferred in some of the applications.…”

Micromolding-polymerization as a novel method for production of nonspherical polymer particles: formation mechanism of polystyrene particles

“…In the past years, several efforts have been done to prepare such particles using different techniques [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. We also reported the production of particles with a variety of shapes [19][20][21][22][23][24]. However, in all of such reports, nonspherical particles have been produced by changing the shape of a precursor; therefore, this question would be raised: Bis it feasible to prepare nonspherical particles of one component directly by polymerization without changing the shape of a precursor?Î n our previous work, we answered this question by introducing a new synthesis method which we called it micromolding-polymerization.…”