Rationally designed anionic diblock copolymer worm gels are useful model systems for calcite occlusion studies

DOI: 10.1039/C9PY00889F

Authors: Lee A. Fielding (The University of Manchester) , Coit T. Hendley (Cornell University) , Emily Asenath-Smith (Cornell University; US Army Corps of Engineers Engineer Research and Development Center) , Lara A. Estroff (Cornell University) , Steven P. Armes (The University of Sheffield)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Polymer Chemistry , VOL 45

State: Published (Approved)
Published: August 2019
Diamond Proposal Number(s): 9490 , 10237

Abstract: Binary mixtures of anionic and non-ionic macromolecular chain transfer agents (macro-CTAs) are utilized in order to rationally design diblock copolymer nanoparticles with tunable morphologies and anionic character via pseudo-living radical polymerization. More specifically, poly(methacrylic acid) (PMAA) and poly(glycerol monomethacrylate) (PGMA) macro-CTAs are pre-mixed prior to reversible addition–fragmentation chain transfer (RAFT) aqueous dispersion polymerization of 2-hydroxypropyl methacrylate (HPMA). This strategy facilitates the formation of PHPMA-based diblock copolymer spheres, worm-like micelles and vesicles via polymerization-induced self-assembly (PISA). The presence of the anionic PMAA stabilizer block has a dramatic impact on the resulting copolymer morphology, particularly if the degree of polymerization (DP) of the PMAA stabilizer chains is longer than that of the PGMA. Two phase diagrams have been constructed to investigate the effect of the relative proportion and molar mass of the two macro-CTAs. Such a systematic approach is essential for the reproducible synthesis of pure worm-like micelles, which occupy relatively narrow phase space. The rheological behavior of a series of soft, free-standing worm gels is investigated. Finally, such gels are examined as model matrices for the growth of biomimetic calcite crystals and the role of the anionic PMAA stabilizer chains in directing crystal growth is evaluated.

Diamond Keywords: Biomineralisation

Subject Areas: Chemistry, Materials


Instruments: I22-Small angle scattering & Diffraction

Other Facilities: ESRF

Added On: 12/09/2019 10:15

Discipline Tags:

Soft condensed matter physics Chemistry Materials Science Organic Chemistry Polymer Science

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS)