Welcome to The Gröschel Group

NEWS and ANNOUNCEMENTS

05-08.04.18 Visit at NTNU, Trondheim

André followed an invitation to the Fussum group by Ville Liljeström who is currently Postdoc at the renowned Norwegian University of Science and Technology (NTNU) in Trondheim, Norway. André delivered a talk in the physics colloquium on "Complex Colloids by Self-Assembly" and give an two lectures on Soft Matter. The Fossum group has great expertise in active structuring of colloids using electro hydrodynamic forces as well as long-standing expertise in clay materials. The stay peaked in a long evening of great food and discussions about future trends in materials science as well as potential collaborations.

30.03.18 Paper accepted in MRC

A joint paper got accepted in Macromolecular Rapid Communications with Andrea Steinhaus in the leading first author role. The publication is the first in a series in two ways: first, it deals with confinement assembly of block copolymers and will be followed by more research conducted by Andrea; second, this publication marks the first installment of a hopefully long tradition of papers between the Müllner group @ University of Sydney and the Gröschel-Lab @ UDE.
The paper by Andrea deals with studies on the confinement assembly of molecular diblock bottlebrushes into well-defined axially stacked lamellar discs or bicontinuous networks (depending on block size). The paper shows for the first time that polymer topologies such as bottle brushes have an impact on the way multicompartment microparticles develop. The bottlebrushes were provided by the Müllner group.

Paper 32 Toc

15.03.2018 Presentation in TU Dortmund

On 15.03.18 André went to TU Dortmund to give a talk on "Self-Assembled Colloids: Builduing Particles from the Bottom-Up" in the polymer seminar on invitation of Prof Jörg Tiller. After the talk there were very fruitful discussions with the Tiller group but also with Ralf Weberskirch from the organic Chemistry department postentially leading to new collaborations. The short trip to the neighbouring university was very inspiring and strengthend the polymer links within the UA RUHR.

13.03.2018 Delivery of Laboratory Equipment

Delivery of glasware incl.  drying oven, new glasware for Schlenk set-up, dewars, liquid nitrogen storage tank, pumps, rotaroy evaporator, magnetic stirrers and more. The lab at the NETZ is now well-equipped to conduct organic synthesis, polymerizations, making colloids and advanced materials.

08-11.03.18 Conference in Tsukuba, Japan

From 06.03.-12.03.18 André went to the 2018 Joint Symposium on Energy Materials Science and Technology in Tsukuba to deliver an invited talk on "Block Copolymer Templates for Energy Applications". The conference is the 8th installment in a series aiming at joint research between several institutes around the world, where CENIDE acts as one of the driving forces (the 6th Symposium was held 2016 at the NETZ ).
The Symposium featured 35 presentations and about the same numebr of posters.
Overall the conferecne was a very enligthening trip into the world of energy materials and the culture of Japan.
A news section on the conference can also be found here.

02.03.2018 Publication in ACS Nano

In the Article "Block Copolymer Micelles for Photonic Fluids and Crystals" we describe the precision assembly of block copolymers to micelles with super- stretched corona, yet with narrow size distribution to qualify as building blocks for tunable and reversible micellar photonic fluids (MPFs) and micellar photonic crystals (MPCs).

Paper 31 Toc


The BCMs form free-flowing MPFs with an average interparticle distance of 150−300 nm as defined by the electrosteric repulsion arising from the highly charged and stretched corona. Under quiescent conditions, millimeter-sized free-floating MPCs with classical FCC lattice grow in the photonic fluid-medium upon refinement of the positional order of the BCMs. We discuss the generic properties of MPCs with special emphasis on surprisingly narrow reflected wavelengths with full width at half-maximum (fwhm) as small as 1 nm. We expect this concept to open a generic and facile way for self-assembled tunable micellar photonic structures.

21.02. - 23.02.2018 Macromolecular Colloquium in Freiburg '18

In February, the entire group participated the Macromolecular Collouium 2018 In Freiburg. The conference featured 3 days of packed sessions with insightful talks and poster presentations.
Andrea Steinhaus was able to acquire one of highly competitive poster slots and gave an excellent presentation on the confinement assembly of triblock terpolymers to generate Janus nanorings. This is probably the first and only time a doughnut filled the entire wall of the auditorium. The poster attrackted much attention with much discussion at the poster stand (doughnuts included!). 

News Freiburg

Overall it was a packed trip with evening gatherings, talks, discussions and dinners. The group made connections to other researchers and gathered much experience at the biggest conference on macromolecular chemsitry in Germany.

20.02.2018 CENIDE Conference: Bergisch Gladbach, Germany

The 3rd CENIDE conference took place from 19-21.02. at the Karl-Schulte Haus in Bergisch Gladbach offering three days of strategic and scientific discussions amongst about 90 participants. The conference featured 21  talks mornign sessions focusing on broad fields of research or introductions to running and planned coordinated programs. Afternoon sessions were divided also into 21 presentations of young researchers highlighting recent research achiements. The scientific programm was further accompanied by poster sessions with 24 posters.

The non-scientific program between sessions and in the evening comprised a relaxed atmosphere to exchange experiences, discuss future events and projects. A special highligth certainly was the table-fussball tournament!

For more information on the event click here

12.02.2018 Group Excursion to Carneval in Düsseldorf

The group went to Düsseldorf to participate in the Carneval 2018 as members from "Alice in Wonderland".

Group-carneval

01.02.2018 GPC Extension

New set-up is installed.

Now is a simultaneous detection of polymers in THF and DMAc with different RI und multi-wave UV possible.

31.01.18 PC/ThC Colloquium - Prof. Dr. Markus Retsch

Prof. Dr. Markus Retsch, Lichtenberg-Juniorprofessur for Polymer Systems at University Bayreuth, gave a talk about thermal transport in nano- and mesostructured colloidal crystals.

TOC graphic to the paper

08.12.17 Publication in Polymer Chemistry

In the article "Supracolloidal Chains of Patchy Micelles in Water" Tai-Lam Nghiem and Tina I. Löbling synthesized a series of bishydrophilic triblock terpolymers via RAFT polymerization with the aim to form supracolloidal chains through a hierarcchical self-assembly process. For that, Tai assembled the terpoylmers PEO-b-PS-b-P2VP in "soft" organic solvents to obtain very homogeneous micelles with a PS core and mixed/patchy corona of PEO/P2VP. Transfer to water pH2 then stabilized these micelles due to the double hydrophilic corona. In pH6 however, P2VP collapses and micelles start to form supracolloidal chains of different length and connectivity. The superstructures were analyzed with DLS in our laboratory as well as TEM in the Imaging Center Essen. Follow-up work will focus on polymorphism as well as different stimuli for supracolloidal structure formation.

link to paper

01.12.17 New group member Alexander Tjaberings

We welcome Alexander Tjaberings from UDE who joined the group on 01.12.17.

He will do his PhD in the Emmy Noether Independent Junior Research Group on the synthesis of functional triblock terpoylmers and their self-assembly into topographic nanoparticles and 3D nanoparticle lattices.

01.12.17 New group member Giada Quintieri

We welcome Giada Quintieri from RUB who joined the group on 01.12.17.

She will do her PhD in the Emmy Noether Independent Junior Research Group on the synthesis of functional triblock terpoylmers and their self-assembly into topographic nanoparticles and 3D nanoparticle lattices.

01.12.17 New group member Ramzi Chakroun

We welcome Ramzi Chakroun to our group who joined on 01.12.17!

He will be responsible for our dynamic light scattering setup and do his PhD on self-assembled triblock terpolymer nanostructures with special emphasis on following self-assembly kinetics and structure evolution in solution.

Stefanie Tjaberings

15.11.17 New group member Stefanie Tjaberings

We welcome Stefanie Tjaberings from UDE who joined the group on 15.11.17.

She will do her PhD on complex block copolymer nanostructrues with special emphasis on block copolymer/metal hybrid materials for energy conversion.

10.11.17 Publication in Polymer Chemistry

In the article "Polymer brush guided templating on well-defined rod-like cellulose nanocrystals" Maria Morits synthesized cylindrical polymer brushes by grafting diverse polymer chains from the backbone of cellulose nanocrystals (CNCs). CNCs are rod-like nanoparticcles of purely crystalline cellulose and have attracted much attention. These biomaterials are usually incompatible with many other materials and compatibilization of the surface further applications is necessary. Maria could show that grafting can be realized in controlled manner and that sol gel processes in the polyer shell leads to spatially controlled bioinorganic hybrids.

link to paper

30.10.17 Master Thesis Finished!

Congratulations to Ramzi Chakroun for successfully completing his Master thesis!

25.10.2017 Publication in Advanced Science

In the article "Imaging Inelastic Fracture Processes in Biomimetic Nanocomposites and Nacre by Laser Speckle for Better Toughness" Tuukka Verho studies the behaviour of nacre mimetic nanocomposites under flexural stress and analyses the deformation with laser speckle imaging. We find that this technique allows detecting plastic deformations before crack formation and provides insight into origin and propagation of cracks. We compared the results with measurements on real nacre samples and find differences in failure bahaviour. These results will help in the design of better matrix/reinforcement adhesion to further boost the performance of lightweight structural bionanocomposites.

23.10.2017 Publication in Advanced Materials

In the Review "Novel materials through assembly of nanocelluloses" we summerize the exponentially growing field on nanocellulose and functional materials derived thereof. This extensive review covers amongst others synthesis and properties of diverse nanocelluloses, processing with polymers, grating polymers from cellulose, cellulose protein and nanoparticles nanocomposites, fiberspinning, hydrogels, biomimetic nanocomposites, nanocellulose materials with magnetic, conductive, optic and catalytic properties.

Chen Chen

16.10.17 New group member Chen Chen

We welcome Chen Chen from Sichuan University in China who joined the group on 16.10.17. He received the prestigeous CSC Scholarship and will do his PhD within the next 48 months. He will be working on polymer self-assembly and precise nanoparticle clusters.

Xiaoliang Qiang

22.09.17 New group member Xiaoliang Qiang

We welcome Xiaolian Qiang from Sichuan University in China who joined the group on 22.09.17. She received the prestigeous CSC Scholarship and will do her PhD within the next 48 months. She will be working on block copolymer self-assembly, nanoemulsions, and topologically complex particles.

15.09.17 Master Thesis Finished!

Congratulations to Stefanie Tjaberings for successfully completing her Master thesis!

Prof. Weian Zhang

15.09.17 Guest Presentation on Photodynamic Therapy by Prof. Weian Zhang

Prof. Weian Zhang from the East China University of Science and Technology (Shanghai, China) visited the group on Friday 15.09.2017 and gave a talk on a series of porphyrin-containing polymers using porphyrins as initiators, monomers, RAFT transfer agents and “click chemistry” agents. He presented a variety of assemblies based on porphyrin-containing amphiphilic polymers useful in photodynamic therapy (PDT), where assemblies effectively improve the water solubility of the porphyrinic photosensitizers and enhance cellular internalization.

BA Suna

06.09.17 Bachelor Thesis Finished!

We congratulate Suna Azhdari for successfully completing her Bachelor thesis.

02.09.17 3 PhD Positions available

We are currently serching for 3 talented PhD students conducting research as part of an Emmy Noether Project launching November 2017. If you are a highly motivated researcher with background or interest in polymer and colloid science you can apply until 29.09.2017.

Links to the job offers can be found here 1 Position and here 2 Positions

05.08.2017 On the Move!

​The group is working on interdisciplary projects (see research) and energy conversion is one of them. Many synthetic concepts and matrials in our group may serve as advanced scaffolds and templates for catalytic materials, separators, and compatibilizers. Since the group is also expanding quickly, the current laboratories at the Schützenbahn are not sufficient anymore. Thus, we applied for laboratory space at the newly errected nano energy technic centre (NETZ) and are now allowed to move into more sophisticated research environment! From mid Semptember onwards the group will be mainly located here and is looking forward to fruitful collaborations and a great time at the NETZ.

Logo of the Emmy Noether Programm

31.07.2017 Emmy-Noether Programm

​The application for an Emmy Noether Independent Research Group was accepted by the German Research Fundation (DFG). From today onwards, the Gröschel Group is one of four Emmy Noether Groups in Polymer Chemistry in Germany and thus, part of an elite network withint the Emmy Noether Programm.

link to news

SI-ATRP from nanoccellulose

10.07.2017 Publication in ACS Sustainable Chemistry & Engineering

In the article "Polymer Brushes on Cellulose Nanofibers: Modification SI-ATRP, and Unexpected Degradation Processes" Maria Morits explores routs to modify cellulose nanofibers for controlled radical surface-initiated polymerization. Nanocelluloses are fascinating biomaterials harvested from plants trees and other biological sources. Nanocelluloses have received much attention reccently due to their exceptional mechanical properties while being a green material with low ecological footprint. To make nanoccellulsoes attractive for various applications, compatibilization through surface modification is necessary. Concepts are in demand and successful SI-ATRP opens a whole new toolbox for diverse chemical surface functions through choie of monomer.

link

Logo of the conference

17.07. – 21.07.2017 16th ICC Clay Conference in Granada

Upon invitation from the organizers, André traveled to Granada to give a talk on 20.07. at 42 °C on "Fracture properties of nacre-mimetic clay-based bionanocomposites". The conference took place in the scienec park of Granada, which was an interesting place with lots to discover. The excursion to Alhambra was a very special trip into an old city with marvelous architecture and designs. André Gröschel acknowledges the DAAD for supporting this trip to a really interesting conference, where polymer chemistry meets high value silicates to creat novel functional materials.

TOC (by Gröschel)

05.07.2017​​​ Highlight in Angewandte Chemie

In "Block Copolymer Micelles with Inverted Morphologies" we highlight an emerging field in polymer research dealing with the self-assembly of highly asymmetric block copolymers into inverse micelles (see also research). Inverse micelles are obtained when the hydrophobic block becomes large enough so that the packing parameter becomes larger than one (p > 1). Fascinating microparticles develop with nanoscale periodicities and high symmetry lattices (cubic, hexagonal, double diamond,...). This research field is relatively new but bares high application potential given the immense interfacial area the grows linearly with particle size (unlike e.g. vesicles 1/R). Applications range from delivery, storage, replicas and energy conversion. The latter will be part of research conduccted at the nano energy technic centre.

link

26.06.2017 Bachelor Thesis Finished!

We congratulate Alexander Eiland for successfully completing his Bachelor thesis.

17.06. – 24.06.2017 9th International Symposium Molecular Mobility and Order in Polymer Systems

Conference St. Petersburg à photo

14.06.2017 New Bachelor-Project

Suna Azhdari is welcome in our team to prepare her bachelor thesis on  polystyrenesulfonate containing  block copoylmers.

07.06. – 08-07.2017 Physics Lecture in Luxenbourg

Trip to Luxembourg

23.05.2017 Guest Talk of Polyferrocenes by Dr.-Ing. Markus Gallei

Markus Galei from the TU Darmstadt visited the group to discuss projects and gave a presentation on ferrocene based polymers and advanced materials applications at the UDE. In the evening we went to dinner with the entire group.

18.05. – 21.05.2017 HYBER Meeting in Helsinki

Conference Helsinki à photo

17.05.2017 Inaugural and GDCh Lecture

The first inaugural lecture in the frame of a GDCH lecture given by André presenting the work of the group and work to come infront of a big audience. After the talk everyone enjoyed beer, bratwurst and bretzel. Special thanks to Andrea, Tai for setting up the evening event, Sebastian for standing behind the grill (andmaking excellent saussages/steaks) and Suna for documenting everything with her camera. Some selected photos can be found in the gallery here.

Ramzi Chakroun

15.05.2017 New Master-Project

Ramzi Chakroun has started his master thesis, after he successfully completed his advanced labcourse on block copoylmer self-assembliesin solution at our working group

Bottrop

12.05.2017 Group Excursion

The group went to the horror labyrinth in Bottrop and later to dinner at Woodpeckers

Group photo of speakers

09.05. – 10.05.2017 Symposium at MPI-Polymer Research, Mainz

Symposium at the MPI-Polymer Research, Mainz, in honour of Prof Axel H.E. Müllers 70th Birthday. The organizers Felix Schacher, Markus Retsch, Anja Goldmann, Andreas Walther and André Gröschel could bring together an exciting line-up of world renowned researchers: Line-up The two days were are great success sharing ideas and getting together with good food and drinks (topped of with a Janus Cake).

02.05.2017 Chinese Guests & Evonik Fellows

Joint seminar between six Evonik fellows at UDE and six visiting Evonik fellows Jiao Tong University, Shanghai China. Together with Dr. Felix Müller from Evonik we organized an afternoon full of presenations and research discussions with newest results from both universities. Our thanks to the visitors and André is looking forward to travel to the partner university next year.

03.05.2017 New Instruments Arrived!

The groups first Size-Exclusion Chromatigraphy (SEC/GPC) arrived for polymer characterization. The GPC was sucessfully installed and is running on THF or DMAc/LiBr. At the same time a Flow Box arrived which will allow to prepare samples free of any dust for light scattering experiemnts. Some photos of hte instruments can be found in the gallery here.

31.04.2017 New Master-Project

Stefanie Tjaberings has started her master thesis, after successfully completing her advanced labcourse on block copoylmer templates for hybrids materials within the group.

05.04. – 07.04.2017 13th Zsigmondy Colloquium of the German Colloid Society

Talk in Saarbrücken on "Block Copolymer Hexosomes"

03.04.2017 New Bachelor-Project

Alexander Eiland is welcome to our team to conduct his bachelor thesis on PEGylation of gold nanoparticles for SERS applications

21.03.2017 Visit in Leiden (Netherlands)

Tai-Lam Nghiem and Andrea Steinhaus are visiting the University in Leiden (Netherlands) to be instructed in cryo-TEM measurements.

04.03. – 12.03.2017 5th International Conference on Multifunctional, Hybrid and Nanomaterials

Conference Lisbon giving a talk on "Nanoparticles with chemical and structural topography" and serving as chairman.

15.02. – 18.02.2017 Macromolecular Colloquium in Freiburg

The first conference visit of the entire group. great experiencce and insightful talks at the biggest conference on macromolecular chemsitry in germany (as always). The group will visit the next year for sure. The program can be found here.

15.02.2017 New Group Member

The group welcomes M.Sc. Andrea Steinhaus. She just started her PhD on block copolymer microphases in the confinement of nanoemulsions with the aim to create complex microparticles, porous latex particles and novel soft nanoparticles.

09.02.2017 First GDCh Lecture

André gave his first GDCh Lecture while visiting Prof. Thomas Hellweg of the Physical Chemsitry Department at the Universit of Bielefeld. The presentation was titled "From coffee mugs and doughnuts to complex soft matter nanostructures" and deals with novel block copolymer nanostructures that are decortated with specific surface pattern. In particular, tstriped patterns on flat and curved objects and the emergence of inevitable topological defects. These defects adapt to the substrate curvature and follow specific mathematical rules that are universal from magnetic monopols to everybodies hair to galaxies. Before and after the presentation there was much discussion with research groups in Bielefeld with potential projects developing on emulsion polymerization and micromulsions.

Flyer CENIDE Talk

18.01.2017 CENIDE Science Talk

Together with our guest Prof. Olli Ikkala of the Aalto University, Helsinki Finland, André is presenting the recent results on Toughness and fracture properties iof self-assembled biomimetic nanocomposites. The flyer to this event can be found here.

TOC

08.12.2016 Publication in Advanced funcitional materials

The article "Toughness and fracture properties in nacre-mimetic clay/polymer nanocomposities" combines biomimetics, materials science and engineering. Maria Morits was able to creat ethe first bulk nanocomposite with globally aligned nanoplatelets (2D clay platelets 1nm thickness). These materials exhibit high strength (250MPa) and stiffness (25GPa), and display toughness, whrere fracture mechanics stringly depend on relative humidity. Interestingly, the material is tough in wet conditions due to plasticity and tough in dry state due to stepwise frature. We estimate the maximum modulus to 70GPa and strength of 500MPa provided more defined (synthetic) clays are used as compared to the natural ones.

 

TOC

22.08.2016 Publication in ACS Macro Letters

In the paper "Rod-like nanoparticles with striped and helical topography" Jani-Markus Malho modified cellulose nanocrystlas (CNCs) with polyelectrolyte brushes through surfaceinitiated atom transfer radical polymerization (SI-ATRP). After complexation of the brushes with complementarily charged block copolymers, the surface spontaneously changed its shape to adopt a screw-like morphology or helix. well-developed helices were monohelices which is untypical in spontaneous self-assembly processes. The Structures were analyszed with cryogenic electron tomography, one of the most advanced imaging techniques in nanosciencce.

TOC

22.08.2016 Publication in ACS Macro Letters

in the paper "Controlling Multicompartment Morphologies using Solvent Conditions and Chemical Modification" Tina Löbling studied possibilities to alter the morphology of triblock terpoylmers in selective solvents. We utilized versatile thiol-ene click reactions to change the volume of one of the blocks as well as the interaction parameters. Amongst the morphologies we found double helices and triple helices.

Tai

01.08.2016 New Group Member

The group welcomes M.Sc. Tai-Lam Nghiem. He just started his PhD on "Complex block copolymer self-assemblies" with the aim to create stimuli-responsive superstructures, precise colloidal polymers, and interpolyelectrylyte complexes. Information about him can be found here and his personal page is here.

TOC graphic

31.05.2016 Publication in Polymer

In the paper "Controlling the shape of Janus nanostructures through supramolecular modification of ABC terpolymer bulk morphologies" panu Hiekkataipale analyses bulk morphologies of ABC triblock terpoylmers with supramolecular binding sites. The poly(4-vinylpyridine) (P4VP) is able to accomodate various organic compounds through hydrogen-bonding. We utilized this feature to attach photoresponsive azobenzene moieties thereby changing the volume fraction of the P4VP phase and hence the morphology. We were able to create various Janus nanostructures from one single terpolymer including Janus cylinders, Janus sheets, and novel hexagonally perforated Janus sheets.

Patchy micelles

09.05.2016 Publication in Nature Communication

In the paper "Rational design of ABC triblock terpolymer solution nanostructures with controlled patch morphology" Tina Löbling synthesized 14 ABC triblock terpolymers and studied their hierarchical self-assembly in selective solvents. We found that a large range of previously unknown nanostructure can not only be generated but also targeted with proper planning of the block composition. We thereby subdivided the four solution topologies known since the year 1995 (spheres, cylinders, sheesta and vesicles) into four new subclasses, including patchy cylinders, double helical cylinders, perforated sheets and striped and perforated vesicles.