Polymer film synthesis from an aqueous latex of polymerization-induced self-assembly (PISA) derived nanofibers

Tensile benefits of nanofibers in commercial paint films

“…67 When exploring the reasons for this deviation from literature results, one must consider both the fibers and the matrix. The nanofibers in this work were produced at a larger, ∼25 g scale than previously reported gram-scale investigations, 18,22,29–32 with a capability to move towards industrial-scale synthesis demonstrated by a further kilogram-scale nanofiber synthesis (Fig. S8†).…”

“…9 In combination with RAFT, polymerization-induced self-assembly (PISA) 10 has been used to synthesize nano-assemblies of various shapes including micelles, vesicles, 11 snowman or football shaped particles, 12 capsules and fibers. 9,13 The great versatility of PISA is derived through selection of the macromolecular chain transfer agent, 14,15 with glass transition temperature (T g ) of the core-forming block, 16 water solubility of the core monomer, 17 and degree of protonation and solvophilicity of the macro-RAFT agent 18 all being factors that can influence assembly behaviour. Nanofibers have been synthesized both in non-aqueous environments 16,19,20 and via aqueous emulsion polymerization.…”

“…31,32 Polymer films formed by anisotropic nanofibers have been shown to be stronger and more extensible than films comprising spherical particles of a similar composition due to physical crosslinking caused by fiber entanglement. 18 Some natural fibers also show promise in improving tensile properties: cellulose nanofibers have been shown to increase the tensile strength and decrease the extensibility of a water-based acryl resin wood undercoat, 33 whereas a high loading of 10 wt% has been shown to significantly improve the strength and extensibility of usually fragile waterborne sulfopolyester coatings. 34 However, most nanofibers have been studied in simple model coatings, such as clear polymer films, with less research published on their impacts on pigmented paint coatings.…”

Effects of stirring rate on morphology of aqueous RAFT emulsion PISA-derived block copolymer nanoparticles

“…The RAFT agents BTPA and CTBPA (Z-group with C4 alkyl chain) are soluble in water, thus enabling the macroRAFT syntheses to be conducted in water followed by direct use of the obtained macroRAFT agents without purification for the subsequent emulsion PISA steps. 25,35…”

“…17,18 When the hydrophilic corona-forming block contains a polyacid or polybase, the morphology can be influenced by the salt concentration 19,20 and the pH. 21–25 The polymerization temperature can also affect the nucleation mechanism and the packing parameter P due to the change in the interaction parameters between polymer/polymer and polymer/solvent. 26 Furthermore, the presence of adequate mixing is understood to be required to obtain nanoparticles with high-order morphologies as it promotes fusion between spherical nanoparticles.…”