Polymerization‐Induced Self‐Assembly: From Macromolecular Engineering Toward Applications

Abstract

Polymerization‐induced self‐assembly (PISA) is nowadays a well‐established technology that is gaining more and more attention from academics and in the industry. It relies on the extension of a solvophilic reactive chain in heterogeneous polymerization conditions. An amphiphilic block copolymer is generated and concomitantly to the growth of the solvophobic block, self‐assembly occurs. PISA was initially developed to achieve radical emulsion polymerizations in the absence of low molecular weight surfactants in order to produce surfactant‐free latexes. Shortly after, it became clear that this technology had also great potential to synthesize well‐defined amphiphilic block copolymers. Finally, researchers became more and more interested in the formed particles themselves (mainly spheres, but also worm and vesicles) and tried to functionalize them for a large variety of applications. In this article, we will start with reviewing the different PISA polymerization techniques, and highlight the possibility to use PISA as a tool to synthesize well‐defined, functional, and complex macromolecular architectures. We will then discuss the main parameters that control the particle morphology, before presenting applications of PISA‐derived particles and dispersions. The article cites more than 400 references, and presents for each polymerization technique a great number of the existing systems in tabular format.

Biobased homopolymers and amphiphilic diblock copolymers containing guaiacyl (G) or hydroxyphenyl (H) lignin derivatives synthesized by RAFT (PISA)

“…worms or vesicles, was observed, as with PAA- b -PS diblock copolymers synthesized under comparable conditions. 44,49 Despite this observation, these biobased latexes, which remained stable for more than a year, remain attractive for paint, coating or adhesive applications. 50,51…”

Unimer Exchange Is not Necessary for Morphological Transitions in Polymerization‐Induced Self‐Assembly

“…Not only spheres can be prepared, but also higher order morphologies (such as worms or vesicles). The latter are of particular interest because they find use in many applications, for instance as viscosity modifiers or soft hydrogels (worms), [3] or as nanoreactors [4] and drug delivery systems (vesicles) [5, 6] . For diblock copolymers, the morphology is thermodynamically dictated by the packing parameter [7] which is defined as p = V /( a l ) where V is the volume occupied by the solvophobic B block, l its length and a the contact surface between the two blocks.…”

“…The latter are of particular interest because they find use in many applications, for instance as viscosity modifiers or soft hydrogels (worms), [3] or as nanoreactors [4] and drug delivery systems (vesicles). [5,6] For diblock copolymers, the morphology is thermodynamically dictated by the packing parameter [7] which is defined as p = V/(a l) where V is the volume occupied by the solvophobic B block, l its length and a the contact surface between the two blocks. As the size of the B block increases during polymerization, so does p. Therefore, higher order morphologies should eventually always be obtained in PISA from a thermodynamic point of view, at least for short and uncharged solvophilic blocks.…”

Rational design of stimuli‐responsive magnetic polymer hybrid (nano)materials

“…To avoid time-consuming extra steps and the use of organic solvents and to overcome inherent limitations in upscaling, the polymerization-induced self-assembly (PISA) [144][145][146][147] technology appears an interesting alternative. Indeed, this technique allows the simultaneous synthesis and self-assembly of amphiphilic block copolymers into nano-objects, directly in water, without any purification step required and at high solid content (generally about 20 wt%).…”