Synthesis of microspheres with microphase-separated shells

Abstract

Novel structural microspheres of the Janus type, with microphase‐separated polystyrene (PS) and poly(tert‐butyl methacrylate) (PBMA) shells and crosslinked poly(2‐vinyl pyridine) (PVP) cores, were synthesized with the crosslinking of PVP spherical domains in poly(styrene‐block‐2‐vinyl pyridine‐block‐tert‐butyl methacrylate) ABC triblock terpolymer film with PS/PBMA lamellae–PVP spherical structures. For the formation of lamellae‐sphere structures, toluene, which was a selective solvent for the ABC triblock terpolymer, was used. With the crosslinking of PVP spheres in the microphase‐separated film with 1,4‐diiodobutane gas, the microphase structure of the terpolymer was fixed, and microspheres composed of microphase‐separated PS and PBMA shells and P2VP cores were obtained. The size distribution of the purified microspheres was narrow. The characteristics of the microspheres and their aggregation behaviors in selective solvents were investigated by transmission electron microscopy and light scattering methods. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2091–2097, 2000

Micellization of block copolymers

“…a PS -PB -PMMA triblock copolymer having a typical PB sphere -PS/PMMA lamellar mesomorphic structure in the solide state. Similar results on 'Janus' micelles were also reported by Saito et al [283].…”

Undulated Multicompartment Cylinders by the Controlled and Directed Stacking of Polymer Micelles with a Compartmentalized Corona

“…Depending on the solubility character of the three blocks, micelles formed by block terpolymers can be divided into two classes: micelles with a compartmentalized core11, 14–16 and with a compartmentalized corona 17–28. In the second class, micellar structures with noncentrosymmetric coronas—Janus particles [29] —are particularly interesting because of their appealing properties, and have been targeted by us20, 23, 30 and other research groups 24. 31 Most of the strategies for the preparation of these Janus particles transfer the morphologies of well‐defined bulk structures into solution by controlled cross‐linking processes 32–34…”

Self‐Assembly of Multiblock Copolymers

“…The first polymer‐based JNPs were realized via lamella bulk morphologies of ABC triblock terpolymers . Exemplified on PS‐ b ‐PB‐ b ‐PMMA and the lamella‐sphere ( ls ) morphology (PS‐lamella/PB‐sphere/PMMA‐lamella) Janus nanospheres (JNSs) were obtained by cross‐linking the PB domain and redispersion in THF .…”