Semi-crystalline diblock copolymer nano-objects prepared via RAFT alcoholic dispersion polymerization of stearyl methacrylate

Abstract

nano-objects prepared via RAFT alcoholic dispersion polymerization of stearyl methacrylate. Polymer Chemistry, 6 (10). pp. 1751 -1757 . ISSN 1759 https://doi.org/10.1039/c4py01664e eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. Semi-Crystalline Diblock Copolymer Nano-Objects Prepared via RAFT Alcoholic Dispersion Polymerization of Stearyl MethacrylateMona Semsarilar, Nicholas J. W. Penfold, Elizabeth R. Jones and Steven P. Armes* Abstract. The RAFT dispersion polymerization of stearyl methacrylate (SMA) is conducted in ethanol at 70°C using a poly(2-(dimethylamino)ethyl methacrylate) [PDMA] chain transfer agent. The growing PSMA block becomes insoluble in ethanol, which leads to polymerization-induced self-assembly (PISA) and hence produces a range of copolymer morphologies depending on the precise PDMA y -PSMA x formulation. More specifically, pure phases corresponding to either spherical nanoparticles, worm-like nanoparticles or vesicles can be prepared as judged by transmission electron microscopy. However, the worm phase space is relatively narrow, so construction of a detailed phase diagram is required for reproducible syntheses of this morphology. Interdigitation of the stearyl (C 18 ) side-groups leads to a semi-crystalline PSMA core block and the effect of systematically varying the mean degree of polymerization of both the PDMA and PSMA blocks on the T m and T c is investigated using differential scanning calorimetry. Finally, it is demonstrated that these cationic nanoparticles can be employed as colloidal templates for the in situ deposition of silica from aqueous solution.

Polymerization-induced self-assembly of block copolymer nanoparticles via RAFT non-aqueous dispersion polymerization

“…For example, Charleux and co-workers conducted the RAFT dispersion polymerization of a bespoke cholestryl-based (meth)acrylic core-forming monomer in an ethanol/water mixture to produce well-defined diblock copolymer nanorods and nanofibers [44]. Similarly, Armes and coworkers conducted the RAFT dispersion polymerization of stearyl methacrylate (SMA) in pure ethanol using a PDMA macro-CTA (Figure 2c) [86]. The latter approach yielded PDMA-PSMA spheres, worms or vesicles with semi-crystalline stearyl side-chains in the PSMA core-forming block [86].…”

“…Similarly, Armes and coworkers conducted the RAFT dispersion polymerization of stearyl methacrylate (SMA) in pure ethanol using a PDMA macro-CTA (Figure 2c) [86]. The latter approach yielded PDMA-PSMA spheres, worms or vesicles with semi-crystalline stearyl side-chains in the PSMA core-forming block [86]. Potential advantages for such nano-objects could be the preparation of relatively stiff worms of tunable flexibility and perhaps also vesicles with less permeable membranes, thus offering enhanced encapsulation efficiency.…”

Polymerization induced self-assembly: tuning of morphology using ionic strength and pH

“…[44][45][46] Lansalot and Carlmark 38 conducted RAFT emulsion polymerization based on the PISA process to obtain spherical particles comprising P(DMAEMA-stat-MAA)-b-PMMA, and Armes and coworkers reported synthesis of spherical particles of poly(2-(dimethylamino)ethyl methacrylate-b-stearyl methacrylate) (PDMAEMA-b-PSMA) via RAFT dispersion polymerization in ethanol. 37 Despite the potential of tuning the charge density of P(DMAEMA) by adjustment of the pH, to the best of our knowledge there are no precedents of exploiting this property to tune the PISA particle morphology beyond spherical particles.…”

“…Polymeric nanoparticles comprising block copolymers with cationic, 28,34,[36][37][38] anionic 25,39,40 and zwitterionic 41,42 character have been synthesised via PISA. In both dispersion and emulsion-based PISA systems, it has been shown that the morphology is influenced by the charge density of the solvophilic block -if the charge density is too high, only spheres can form due to the strong repulsive forces between the chains on decreasing the curvature of the interface between the core and the continuous phase.…”

Poly( N -2-(methacryloyloxy)ethyl pyrrolidone)-poly(benzyl methacrylate) diblock copolymer nano-objects via RAFT alcoholic dispersion polymerisation in ethanol

“…[29][30][31][32][33][34][35][36] Pan and co-workers have made a number of notable contributions to the field of RAFT alcoholic dispersion polymerisation [37][38][39][40]. Their approach typically involves chain extension of a soluble macro-CTA such as poly(2-dimethylaminoethyl methacrylate) with styrene in methanol [37].…”