Talk

Monday, September 17, 2018

Speaker
Maria Vamvakaki
Affiliation
Department of Materials Science and Technology, University of Crete and IESL, FORTH
Title
Functional and Stimuli-Responsive "Smart" Polymers
Location
Room A2 (A115-A117) of CSD Building (ground floor, north wing)
Time
12:00
Language
English
Abstract

Functional and stimuli-responsive synthetic polymers represent one of the most exciting and emerging areas of scientific interest with a wide range of potential applications in nano- and bio-technology.1 During the last three decades, scientists have been trying to mimic nature in designing “smart” synthetic materials, using various functional molecular building blocks, for a plethora of applications, including sensors, logic operations, biomedicine, tissue engineering, synthetic muscles, “smart” optical/electromechanical systems, membranes, electronics and “smart” surfaces.2 Herein our latest developments in this field3,4 are presented.

In the first part of my talk, I will discuss our recent approaches towards the development of versatile, multi-functional polymer surfaces exhibiting controllable antimicrobial properties in the solid state. Two types of polymeric surfaces were developed comprising (i) antifouling-bactericidal mixed polymer brushes grown on glass/silicon substrates by surface-initiated atom transfer radical polymerization5 and (ii) self-polishing-bactericidal polymer films formed from symmetric amphiphilic diblock copolymers comprising a hydrophobic and hydrolysable block and a hydrophilic, cationic polyelectrolyte block synthesized by group transfer polymerization.6 These polymer surfaces exhibit dual antifouling-biocidal and biocidal-self-renewal properties leading to a long-lasting antimicrobial activity and address current limitations in antibacterial/bactericidal surfaces which become inactive when covered by dead bacteria.

In the second part, two types of photo-sensitive materials will be described: (i) triple stimuli-responsive diblock copolymers and hybrid colloidal particles.7 The unpresented light-induced formation and disruption of responsive hollow polymer capsules from hybrid core-shell particles and the synergistic stimulus response of diblock copolymers, which resulted in structural reorganization and hierarchical self-assembly into complex structures in the micro- and milli-scale, was reported; (ii) novel photodegradable polyacetals undergoing main chain scission upon light irradiation.8 The polymer degradation at very low energies, in the absence of free radical intermediates, to produce non-toxic, low molecular weight by-products, was reported for the first time and renders these polymers highly attractive in a variety of applications in the biomedical field such as in cell patterning/harvesting and in photo-controlled drug delivery.

References

  1. M. A. C. Stuart, et al. Nat. Mater. 2010, 9, 101; J.-M. Lehn, Angew. Chem. Int. Ed. 2015, 54, 3276; J. F. Patrick, Nature 2016, 540, 363.
  2. F. Liu and M. W. Urban, Prog. Polym. Sci. 2010, 35, 3; J. L. Silverberg, et al. Nat. Mater. 2015, 14, 389; Z. X. Chen, Science 2017, 357, 475; S. Miao, Mater. Today 2017, 20, 577; E. Stratakis, et al., Chem. Commun. 2010, 46, 4136.
  3. G. Pasparakis and M. Vamvakaki Polym. Chem. 2011, 2, 1234
  4. Th. Manouras and M. Vamvakaki Polym. Chem. 2017, 8, 74.
  5. E. Koufakis et al. submitted 2018.
  6. Th. Manouras, et al. Soft Matter 2017, 13, 3777; Th. Manouras et al. in preparation.
  7. D. S. Achilleos et al. Macromolecules 2010, 43, 7073; J. Am. Chem. Soc. 2012, 134, 5726; Langmuir 2016, 32, 5981. P. G. Falireas and M. Vamvakaki, Macromolecules 2018, accepted and manuscript in preparation.
  8. G. Pasparakis, et al., Macromol. Rapid. Commun. 2012, 33, 183; Angew. Chem. Int. Ed. 2011, 50, 4142; Nat. Commun. 2014, 5, 3623. M. Psarrou et al. in preparation.

For forthcoming colloquia, please see: http://www.materials.uoc.gr/en/colloquia