Kategorie: ‘Polymers’
Polymer Blends & Eurofillers 2025
Paul Marten and Fabian Weitenhagen attended and delivered presentations at Polymer Blends & Eurofillers 2025 in Lyon this week.
Paul Marten presented the “Development and Characterisation of a Composite Material based on Polylactic Acid, Chitin, and Lecithin”.
Fabian Weitenhagen presented “Sustainable Biopolymer Composites Using Recycling Cellulose from Wastepaper”.
Anouncement: Polymer Blends & Eurofillers
We are pleased to announce that two exciting presentations from our working group have been accepted at Polymer Blends & Eurofillers 2025 in Lyon from January 27 to 30, 2025:
Paul Marten
Development and Characterization of a Composite Material based on Polylactic Acid, Chitin, and Lecithin
and
Fabian Weitenhagen
Sustainable Biopolymer Composites Using Recycling Cellulose from Wastepaper
Take the opportunity to learn about the latest results from the working group and to talk directly to the members.
WTA-Days 2024
We were represented with a total of four lectures at the WTA Days 2024, 14-16 March 2024 in Brno, Czech Republic.
Prof Weichold presented a lecture entitled ‘Alkaline hydrogels as multifunctional repair materials’. From the field of bio-based construction materials, Fabian Weitenhagen gave a presentation on ‘Renewable Polyester Resin Systems for Sustainable Construction Materials’, Paul Marten gave a presentation on ‘Chitosan as a Key Component in the Production of Sustainable Acrylic Glass-Wood Laminates’ and Nils Münstermann gave a presentation on ‘Chitosan as an Eco-Friendly Binder for High-Strength Fibreboards in Sustainable Construction’.
IPC2023
At the 13th Society of Polymer Science Japan (SPSJ) International Polymer Conferences (IPC2023), 18-21 July 2023 in Sapporo, Japan, we were represented with two presentations:
Prof Weichold
Firefighting with feathers
Fabian Weitenhagen
Development of bio-based thermosetting polyester resins
Book chapter
Eine sehr grundlegende Einführung in das Thema Polymerchemie findet sich in
O. Weichold, Introduction to Polymer Chemistry. In: P. Richet, R. Conradt, A. Takada, J. Dyon (Hrsg.) Encyclopedia of Glass Science, Technology, History, and Culture Vol. 2. Wiley-VCH, New York, 2021, S. 1043–1055. https://doi.org/10.1002/9781118801017
New publication
Structure formation in oligomers
How can the thermal stability and crystallinity of oligomers be controlled? Four members of a homologous series of chlorinated poly(vinyl ester) oligomers from poly(vinyl acetate) to poly(vinyl stearate) with degrees of polymerisation of 10 and 20 were prepared by telomerisation with carbon tetrachloride. All oligomers are thermally degraded in two main steps, whereby HCl and side chains are lost before the backbone is degraded. The polymers with short side chains, up to poly(vinyl octanoate), are amorphous and show internal plastification, while those with long side chains are semi-crystalline due to side chain crystallisation. The glass transition and melting temperatures as well as the initial decomposition temperature are more strongly influenced by the side chain length than by the degree of polymerisation. Thermal stability is improved when both the size and the number of side chains increase, but only long side chains lead to a significant increase in decomposition resistance.
D. Heinze, T. Mang, C. Popescu, O. Weichold
Effect of side chain length and degree of polymerization on thedecomposition and crystallization behaviour of chlorinated poly(vinylester) oligomers
Thermochimica Acta 2016, 637, 143-153. http://dx.doi.org/10.1016/j.tca.2016.05.015
Tg, Tm, OMG – Understanding polymers
With every change in a system (e.g. phase transformation, chemical reactions), heat is either absorbed or released. This can be analysed quantitatively using differential scanning calorimetry. We can use a DSC 204 F1 Phoenix from Netzsch to measure cooling and heating processes from approx. -50 to 600 °C. The cooling and heating rates can be set from 0.1 to 100 K•min−1 .
New publication
Poly(vinyl acetate) plasticises itself
No additional plasticiser required. Poly(vinyl acetate), PVAc, with a degree of polymerisation Xn≈10 was produced by free radical chain transfer polymerisation with carbon tetrachloride and used as an oligomeric plasticiser for commercial PVAc. After H/Cl exchange at the chain ends, the product exhibits high thermal stability and excellent melt compounding properties. Blends of oligomeric and commercial PVAc show simple glass transition temperatures, which decrease with higher oligomer content, and exhibit small negative deviations from Fox’s linear additivity rule. This suggests that plasticisation and miscibility are mainly due to entropic effects. Injection moulded thick specimens show ductile behaviour at oligomer contents >10 wt%, while sheets with a thickness of 0.2-0.5 mm appear flexible already at 7.5 wt%. The oxygen permeability coefficients are an order of magnitude lower than those of low-density polyethylene. Due to the sum of their properties, the plasticised sheets represent a promising alternative for the production of barrier materials.
D. Heinze, T. Mang, K. Peter, M. Möller, O. Weichold
Synthesis of Low Molecular Weight Poly(vinyl acetate) and Its Application as Plasticizer
J. Appl. Polym. Sci. 2014, 40226. https://doi.org/10.1002/APP.40226
