Dr
Jan Krawczyk
(Institute of Nuclear Physics PAN, Kraków)
07/07/2015, 17:00
The phase situation and molecular motions of some cyanobiphenyl compounds with different terminal chains were studied in our group using various experimental methods [1-4]. Rich phase polymorphism was found for chiral isomers.
The main topic of this lecture will be two of the liquid crystal glass-formers of this group: (S)-4-(2-methylbutyl)-4'-cyanobiphenyl (5*CB) and...
Ms
Daria Szewczyk
(Institute of Low Temperature and Structure Research PAS)
07/07/2015, 17:20
The measurements of heat capacity and thermal conductivity of the glass-like monoclinic and the stable orthorhombic phases of 2-adamantanone (C10H14O) have been carried out in temperature range 2 K - 300 K. The results of heat capacity determination for the both investigated phases are almost the same, whereas for thermal conductivity measurements substantial differences have been found. The...
Dr
Natalia Osiecka
(Institute of Nuclear Physics PAN, Kraków)
07/07/2015, 17:35
4-hexyloxybenzylidene-4’-dodecyloxyaniline (6BA12) belongs to the 4-hexyloxybenzylidene-4’-alkyloxyanilines homologous series. All derivatives of 6BAn (n=1-12) homologous series exhibit liquid crystal phases. Arrangement of molecules in phase and number of phases increase with the length of alkyloxy tail [1]. During cooling this substance several liquid crystal phases are observed: nematic...
Mr
Wojciech Tomczyk
(Institute of Physics, Jagiellonian University, Kraków)
07/07/2015, 17:50
The discovery of ferroelectric liquid crystals in 1974 by Meyer et al. [1] and later antiferroelectric by Chandani et al. [2] resulted in conducting many researches over these materials due to their promising applications [3]. The aim of this work was to study the molecular dynamics of two homologous thermotropic liquid crystal compounds, in short 6F4BBiOC8 [4] and 8F2BBiOC8....
Mr
Jakub Saramak
(Department of Molecular Physics, Faculty of Chemistry, Lodz University of Technology, Poland)
07/07/2015, 18:05
Polymers, which exhibit lower critical solution temperature (LCST) are a good substrates to design stimuli-responsive materials with many applications such as micro-valves, chemical indicators, drug delivery systems, lenses and many others [1,2]. In such systems three fundamental types of water may be distinguished: “bulk”, primary and secondary bounded water [3]. Knowledge about diffusion of...
Prof.
Friedrich Kremer
(Institute of Experimental Physics I, University of Leipzig, Germany)
09/07/2015, 09:00
soft matter and glassformers
The question on what length-scale molecular and especially glassy dynamics of polymers takes place is of fundamental importance and has multifold practical implications as well. Recent results based on Broadband Dielectric Spectroscopy [1,2] for nanometric thin (≥5 nm) layers of poly(styrene) [3], poly(methylmethacrylate) [4,5] and poly(cis-1,4-isoprene) [6] will be presented,...
Prof.
Michael Wübbenhorst
(KU Leuven, Department of Physics and Astronomy)
09/07/2015, 09:40
soft matter and glassformers
Physical vapor deposition (PVD) of super-cooled liquids into the glassy state yields occasionally glasses with extraordinary high packing density resulting in an extremely low fictive temperature and high kinetic stability [1]. While a couple of organic molecules have been proven to form (ultra)stable glasses, we have recently shown that PVD might also induce enhanced molecular order in...
Prof.
Marco Geppi
(University of Pisa)
09/07/2015, 10:10
Solid state Nuclear Magnetic Resonance Spectroscopy is able to give detailed bulk structural and dynamic information on solid systems and soft matter, representing one of the most powerful characterization techniques in several fields, ranging from pharmaceuticals to polymeric materials, from inorganic compound to hybrids, from liquid crystals to biological systems.
Structural information...
Dr
Claudia Forte
(ICCOM-CNR, Pisa)
09/07/2015, 10:40
Neohexanol (2,2-dimethyl-1-butanol, CH3CH2C(CH3)2CH2OH) and some of its isomers, differing for the positions of the OH and CH3 substituents, constitute a very interesting class of compounds showing a rich polymorphism with several solid-solid phase transitions. Indeed, due to their globular shape and to the possibility to...
Prof.
Wilfried Schranz
(University of Vienna)
09/07/2015, 11:30
soft matter and glassformers
Polyurea elastomeres exhibit phase separated mesoscopic structures with hard nanodomains embedded in a soft (compliant) matrix. This system shows (Fig.1) two glass transitions at Tg1<Tg2, which are related to the freezing of motion of molecular segments in the soft domains (α peak = usual polymer glass transition at Tg1) and to regions of restricted mobility near the hard nanodomains at Tg2...
Prof.
Kazuya Saito
(University of Tsukuba)
09/07/2015, 12:00
Our previous study based on structural thermodynamics [1-3] established that the conformation of alkyl chains attached to the end(s) of the rigid core part of mesogenic molecules is fully molten in any liquid crystalline (LC) mesophases. Besides, recently revealed is that the nano-segregated structure is a fundamental structure for layered (smectic) LCs formed by such molecules [4,5]....
Ms
Yuki Kawata
(Department of Chemistry, University of Tsukuba ; Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST))
09/07/2015, 12:30
Self-healing materials are expected to extend the lifetimes of a variety of products. Recently, we have developed a self-healing material using a particle/liquid-crystal (LC) composite gel containing an azobenzene compound. The particle/azo-doped LC composite gel showed the gel–sol transition by the trans–cis photoisomerization of an azo dopant. The photoinduced gel–sol...
Dr
Ewa Dryzek
(Institute of Nuclear Physics PAN, Kraków)
09/07/2015, 12:50
soft matter and glassformers
Probing of intermolecular or intramolecular regions in molecular solids by positron annihilation lifetime spectroscopy (PALS) is well established. In such substances, the formation and decay of positronium (Ps) – the positron-electron bound state is expected to be influenced by the nature of intermolecular interactions and the internal structure. Structural changes, phase transformations and...
Prof.
Jan Wąsicki
(Faculty of Physics, Adam Mickiewicz University, Poznań, Poland)
09/07/2015, 13:10
Recently, the phenomenon of polymorphism of therapeutic drugs has become the problem of increasing interest because of the common use of drugs in solid form, as tablets, powder inhalations, etc. The form of drug is sensitive to the effect of particular processes applied in drug production. Changes in the external conditions taking place in the process of drug production or storage can induce...
Prof.
Marian Paluch
(Institute of Physics, University of Silesia)
09/07/2015, 17:20
The molecular studies of glass-forming liquids at elevated pressure become now a standard practice in many laboratories all over the word [1]. The addition of pressure as an external thermodynamic variable open a new perspective in understanding the fragility concept. The objective of this presentation is to show that the relaxation dynamics of van der Waals liquids, polymers and ionic liquids...
69.
Effect of pressure on time and length scales of molecular dynamics in the density scaling regime
Dr
Andrzej Grzybowski
(Institute of Physics, University of Silesia)
09/07/2015, 17:50
Our thorough analyses of high pressure experimental data of various glass formers that belong to different material groups (such as van der Waals supercooled liquids, polymer melts, and supercooled ionic liquids) clearly show that some previous suppositions concerning interrelations between time and length scales of molecular dynamics near the glass transition require revisiting. This is a...
Dr
Malgorzata Jasiurkowska-Delaporte
(NanoBioMedical Center, Adam Mickiewicz University, Poznań, Poland)
09/07/2015, 18:05
soft matter and glassformers
Owing to their outstanding physical and chemical properties carbon nanotunes (CNTs) are a promising material with potential applications in drug delivery systems, electronics and aerospace. The major challenge of the practical use of CNTs in medicine is enhancing of their ability to disperse in hydrophilic solvents. Chemical treatment with acids damages the graphite-like structure of CNTs and...
Prof.
Grazyna Bator
(Faculty of Chemistry, University of Wroclaw)
09/07/2015, 18:20
A forecast of the strength of hydrogen bonds in the molecular complexes is important in the designing of the novel organic materials exhibiting polar or semiconducting properties. In such materials, besides the formation of relatively strong hydrogen bonds we expect either the formation of infinite chains of molecules in the crystal lattice or the stacking alignment of molecules, which favors...
Prof.
Zbigniew Galewski
(Faculty of Chemistry, University of Wroclaw, Poland)
09/07/2015, 18:35
Liquid-crystalline azobenzene derivatives are today very important materials in modern opto-electronics [1,2]. Chiral moiety can induce extra new structures and physical properties. In this communication after short review about mesogenic chiral azobenzenes a new series of compounds are presented [3].
Four types of mesophases were identified: chiral nematic, smectic A*, smectic C* and TGBA....
