Professor Goran Ungar

BSc PhD CPhys

Department of Materials Science and Engineering

Emeritus Professor of Polymers and Organic Materials

g.ungar@sheffield.ac.uk

Full contact details

Professor Goran Ungar
Department of Materials Science and Engineering
Sir Robert Hadfield Building
Mappin Street
Sheffield
S1 3JD
Research interests

Two main research areas: The first is the study of structure and phase behaviour of liquid crystalline (l.c.) and supramolecular polymeric and low molecular systems. Molecular organisation is investigated by diffraction, microscopy and spectroscopy. Applying principles of self-assembly, new molecular architectures are designed and tested in collaboration with synthetic chemists. Current topics include molecular channel matrices, liquid crystalline (LC) dendrimers and amphiphiles, soft quasicrystals, novel thermotropic l.c. phases with 2d and 3d periodicity ("micellar", bicontinuouscubic and non-cubic, columnar, honeycomb), controlled shape supramolecularnano-objects, helical self-assembly of organic semiconductors, LC-directed superlattices of metal and semiconductor nanoparticles for photonic and metamaterials, nano-confined LCs highly conducting polymer electrolytes.

The second area of research is structure and morphology of semicrystalline polymers. In particular, monodisperse model polymers in the form of very long n-alkanes are studied. As a result of these studies the "self-poisoning" crystallization mechanisms has been proposed for flexible polymers. Furthermore, new layer structures and superlattices were discovered. New mathematical models allowed us to describe quantitatively the shapes of polymer crystals. We study structure and structure formation of biodegradable and light-emitting polymers, and investigate structure, morphology, and structure formation in semicrystalline polymers, including biodegradable polyesters and copolyesters, as well as in bulk and thin-film nanocomposites containing nanoparticles, nanofibres and graphene.

The development of advanced instrumentation and analytical methods for x-ray and neutron scattering, specifically tailored for liquid crystal and polymer studies, plays a major part in the group's research. Low and wide angle scattering X-ray detectors are incorporated into purpose-built in-house equipment. Synchrotron experiments are carried out where high source brilliance and high resolution are required. Grazing-incidence small- and wide-angle scattering experiments are carried out at ESRF and Diamond synchrotrons and neutron diffraction at ISIS and ILL. Diffraction techniques are complemented with microscopies: optical, TEM, SEM and, in particular, high-resolution AFM.

Much of the research is done in collaboration with Dr. X.B. Zeng.

Key projects:

  • Project Leader of the SCALES network “Complexity across lengthscales in soft matter” funded by European Science Foundation.
  • European FP7 project “Self-Organized Nanomaterials for Tailored Optical and Electrical Properties - NANOGOLD”.
  • “Materials for Renewable Energy Nature's Way (RENEW)” (PIRE scheme, NSF-EPSRC).
Publications

Journal articles

Chapters

Conference proceedings papers

  • Partridge B, Roche C, Sun H-J, Leowanawat P, Araoka F, Sahoo D, Peterca M, Wilson D, Prendergast M, Zeng X , Ungar G et al (2016) Mechanisms for supramolecular helical polymerization into crystalline arrays of chiral columns. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 252 RIS download Bibtex download
  • Partridge B, Leowanawat P, Ho M-S, Peterca M, Sun H-J, Sahoo D, Wu Y-C, Aqad E, Imam M, Graf R , Spiess H et al (2016) Thermodynamically controlled crystallization of self-organizing supramolecular assemblies. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 252 RIS download Bibtex download
  • Percec V, Rosen B, Peterca M, Leowanawat P, Imam M, Partridge B, Zeng X, Ungar G & Heiney P (2016) Materials genome approach to discover and predict hierarchical structures. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 252 RIS download Bibtex download
  • Percec V, Rosen B, Roche C, Partridge B, Sun H-J, Leowanawat P, Peterca M, Araoka F, Zeng X, Ungar G & Heiney P (2016) Why are biological systems homochiral?. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 252 RIS download Bibtex download
  • Roche C, Partridge B, Sun H-J, Leowanawat P, Araoka F, Peterca M, Wilson D, Prendergast M, Zeng X, Ungar G , Heiney P et al (2016) Deracemization of supramolecular assemblies in bulk crystal state. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 252 RIS download Bibtex download
  • Kanie K, Matsubara M, Stevenson W, Yamazaki Y, Yabuki J, Kojima K, Nakaya M, Chichibu SF, Muramatsu A, Zeng X & Ungar G (2016) Liquid-crystalline organic-inorganic hybrid dendrimer with a CdS nano-core: The self-organized structure-dependent photoluminescence behavior. 22nd International Congress of Chemical and Process Engineering, CHISA 2016 and 19th Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction, PRES 2016, Vol. 2 (pp 795-796) RIS download Bibtex download
  • Tadjiev T, Zeng X, Peterca M, Ungar G, Percec V & Leowanawat P (2012) Dendronized perylene bisimides: Soft-crystal structure key to high charge mobility. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 244 RIS download Bibtex download
  • Leowanawat P, Aqad E, Imam MR, Sun H-J, Peterca M, Hudson SD, Ungar G, Zeng X, Graf R, Spiess HW , Heiney PA et al (2012) Self-assembly and self-repairing of complex helical columns based on dendronized perylene bisimides. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 244 RIS download Bibtex download
  • Zheng Y, Liu J, Liao YP, Ungar G & Wright PV (2005) Low dimensional polymer electrolytes with enhanced Li+ conductivities. JOURNAL OF POWER SOURCES, Vol. 146(1-2) (pp 418-422) RIS download Bibtex download
  • Liu J, Zheng Y, Liao YP, Apperley DC, Ungar G & Wright PV (2005) High lithium conductivities in weakly-ionophilic low-dimensional block copolymer electrolytes. ELECTROCHIMICA ACTA, Vol. 50(19) (pp 3815-3826) RIS download Bibtex download
  • Percec V, Smidrkal J, Holerca MN, Nummelin S, Morrison JJ, Glodde M, Golding GM, Balagurusamy VSK, Peterca M, Uchida S , Heiney PA et al (2004) Synthesis, structural and retrostructural analysis of novel AB(2)- and AB(3)-type self-assembled supramolecular dendrimers.. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 228 (pp U62-U63) RIS download Bibtex download
  • Ungar G, Putra EGR, de Silva DSM & Waddon AJ (2004) Events at the growth face as revealed by concentration dependence of crystallization rate of long alkanes.. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 228 (pp U499-U499) RIS download Bibtex download
  • Zeng XB, Liu YS, Ungar G, Percec V & Dulcey AE (2004) Dendrimeric liquid quasicrystal.. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, Vol. 228 (pp U500-U500) RIS download Bibtex download
  • de Silva DSM, Zeng XB, Ungar G & Spells SJ (2003) On perpendicular and tilted chains in lamellar crystals. JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS, Vol. B42(3-4) (pp 915-927) RIS download Bibtex download
  • Ungar G (2003) Columnar phase in main chain and comb-like polymers. MOLECULAR CRYSTALS AND LIQUID CRYSTALS, Vol. 396 (pp 155-168) RIS download Bibtex download
  • Chia FS, Zheng Y, Liu J, Ungar G & Wright PV (2002) Influence of polymer I polymer II compatibility on conductivity in low-dimensional polymer electrolyte blends. SOLID STATE IONICS, Vol. 147(3-4) (pp 275-280) RIS download Bibtex download
  • Zeng XB & Ungar G (2002) Semicrystalline and superlattice structures in binary mixture of long chain n-alkanes C194H390 and C294H590. JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS, Vol. B41(4-6) (pp 1305-1320) RIS download Bibtex download
  • Zheng Y, Chia F, Ungar G & Wright PV (2001) Self-tracking, solvent-free low-dimensional polymer electrolyte blends with lithium salts. JOURNAL OF POWER SOURCES, Vol. 97-8 (pp 641-643) RIS download Bibtex download
  • Zheng YG, Chia FS, Ungar G, Richardson TH & Wright PV (2001) High ambient dc and ac conductivities in solvent-free, low-dimensional polymer electrolyte blends with lithium salts. ELECTROCHIMICA ACTA, Vol. 46(10-11) (pp 1397-1405) RIS download Bibtex download
  • Ungar G, Zeng XB & Spells SJ (2000) Non-integer and mixed integer forms in long n-alkanes observed by real-time LAM spectroscopy and SAXS. POLYMER, Vol. 41(25) (pp 8775-8780) RIS download Bibtex download
  • Grell M, Bradley DDC, Inbasekaran M, Ungar G, Whitehead KS & Woo EP (2000) Intrachain ordered polyfluorene. SYNTHETIC METALS, Vol. 111 (pp 579-581) RIS download Bibtex download
  • Zheng YG, Wright PV & Ungar G (2000) Insertion of ionophobic components into amphiphilic low-dimensional polymer electrolytes. ELECTROCHIMICA ACTA, Vol. 45(8-9) (pp 1161-1165) RIS download Bibtex download
  • Zeng XB & Ungar G (1998) Lamellar structure of non-integer folded and extended long-chain n-alkanes by small-angle X-ray diffraction. POLYMER, Vol. 39(19) (pp 4523-4533) RIS download Bibtex download
  • Wright PV, Zheng Y, Bhatt D, Richardson T & Ungar G (1998) Supramolecular order in new polymer electrolytes. POLYMER INTERNATIONAL, Vol. 47(1) (pp 34-42) RIS download Bibtex download
  • Dias FB, Batty SV, Gupta A, Ungar G, Voss JP & Wright PV (1998) Ionic conduction of lithium, sodium and magnesium salts within organised smectic liquid crystal polymer electrolytes. ELECTROCHIMICA ACTA, Vol. 43(10-11) (pp 1217-1224) RIS download Bibtex download
  • Zheng Y, Dias FB, Wright PV, Ungar G, Bhatt D, Batty SV & Richardson T (1998) Novel alternate layer LB film polymer electrolyte systems. ELECTROCHIMICA ACTA, Vol. 43(10-11) (pp 1633-1637) RIS download Bibtex download
  • Zheng Y, Bhatt D, Dias FB, Batty SV, Tajbakhsh AR, Richardson T, Wright PV & Ungar G (1997) Conductivity of novel, thin-film, heterogeneous polymer electolyte systems. SUPRAMOLECULAR SCIENCE, Vol. 4(3-4) (pp 525-528) RIS download Bibtex download
  • Batty SV, Richardson T, Dias FB, Voss JP, Wright PV & Ungar G (1996) LB films of novel polyethers and their salt complexes. THIN SOLID FILMS, Vol. 285 (pp 530-532) RIS download Bibtex download
  • Boda E, Ungar G & Keller A (1996) Crystallization rate minima in ultra-longn-alkanes. Acta Crystallographica Section A Foundations of Crystallography, Vol. 52(a1) (pp C508-C508) RIS download Bibtex download
  • Percec V, Johansson G, Schlueter D, Ronda JC & Ungar G (1996) Molecular recognition directed self-assembly of tubular supramolecular architectures from building blocks containing monodendrons as exo-receptors and crown- or pseudo-crown-ethers as endo-receptors. MACROMOLECULAR SYMPOSIA, Vol. 101 (pp 43-60) RIS download Bibtex download
  • UNGAR G, ZHOU JP, PERCEC V & CHU PW (1995) NEMATIC, SMECTIC AND COLUMNAR PHASES OF MAIN-CHAIN LIQUID-CRYSTAL POLYETHERS. MACROMOLECULAR SYMPOSIA, Vol. 98 (pp 951-966) RIS download Bibtex download
  • PERCEC V, HECK J, JOHANSSON G, TOMAZOS D & UNGAR G (1994) TOWARDS TOBACCO MOSAIC VIRUS-LIKE SELF-ASSEMBLED SUPRAMOLECULAR ARCHITECTURES. MACROMOLECULAR SYMPOSIA, Vol. 77 (pp 237-265) RIS download Bibtex download
  • PERCEC V, HECK J, JOHANSSON G, TOMAZOS D, KAWASUMI M & UNGAR G (1994) MOLECULAR-RECOGNITION-DIRECTED SELF-ASSEMBLY OF SUPRAMOLECULAR POLYMERS. JOURNAL OF MACROMOLECULAR SCIENCE-PURE AND APPLIED CHEMISTRY, Vol. A31(8) (pp 1031-1070) RIS download Bibtex download
  • PERCEC V, HECK J, JOHANSSON G, TOMAZOS D, KAWASUMI M, CHU P & UNGAR G (1994) MOLECULAR RECOGNITION DIRECTED SELF-ASSEMBLY OF SUPRAMOLECULAR ARCHITECTURES. JOURNAL OF MACROMOLECULAR SCIENCE-PURE AND APPLIED CHEMISTRY, Vol. A31(11) (pp 1719-1758) RIS download Bibtex download
  • ORGAN SJ, KELLER A & UNGAR G (1993) GROWTH, NUCLEATION AND THICKENING RATE MINIMA IN LONG LINEAR ALKANES. CRYSTALLIZATION OF POLYMERS, Vol. 405 (pp 81-86) RIS download Bibtex download
  • UNGAR G (1993) SELF-POISONING OF CRYSTAL-GROWTH FACES IN LONG ALKANES AND POLY(ETHYLENE OXIDE) FRACTIONS. CRYSTALLIZATION OF POLYMERS, Vol. 405 (pp 63-72) RIS download Bibtex download
  • UNGAR G & HILL MJ (1991) LONG-RANGE ACTIVE-SITE TRANSFER IN IRRADIATED HYDROCARBON CRYSTALS. RADIATION PHYSICS AND CHEMISTRY, Vol. 37(1) (pp 37-42) RIS download Bibtex download
  • UNGAR G & KELLER A (1991) RADIATION AND THE CRYSTALS OF POLYETHYLENE AND PARAFFINS. RADIATION EFFECTS ON POLYMERS, Vol. 475 (pp 101-118) RIS download Bibtex download
  • KELLER A, UNGAR G & PERCEC V (1990) LIQUID-CRYSTALLINE POLYMERS - A UNIFYING THERMODYNAMICS-BASED SCHEME. LIQUID-CRYSTALLINE POLYMERS, Vol. 435 (pp 308-334) RIS download Bibtex download
Professional activities
  • IUPAC 2017 Distinguished Award for Novel Materials and their Synthesis
  • Invited speaker at over 80 international conferences
  • Visiting Professor at Universities of Hiroshima, Barcelona, Zhejiang Sci-Tech and Seoul National University
  • On Editorial Board of Polymer Journal
  • Member of the Committee of the British Liquid Crystal Society
  • Member of the Beam Allocation Panel of the UK Synchrotron Radiation Source
  • Member of the EPSRC College
  • Over 10,000 citations, h-index51