@inproceedings{HerzSigruenerKrekemeyeretal.2021, author = {Herz, Jonas and Sigr{\"u}ner, Michael and Krekemeyer, Markus and Kazmi, Monis and Schuster, Jens and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {INVESTIGATION OF AN INNOVATIVE WOOD-PLASTIC HYBRID LAID FABRIC FOR THE REPLACEMENT OF STEEL REINFORCEMENTS IN CONSTRUCTIONS}, series = {SAMPE Europe 2021 Conference, Baden/Z{\"u}rich, 29. - 30. Sept. 2021}, booktitle = {SAMPE Europe 2021 Conference, Baden/Z{\"u}rich, 29. - 30. Sept. 2021}, year = {2021}, language = {en} } @inproceedings{HerzSigruenerWalteretal.2022, author = {Herz, Jonas and Sigr{\"u}ner, Michael and Walter, David and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {Coextruded Polymeric Bicomponent Fibers for Concrete Reinforcements}, series = {SAMPE Europe Conference Proceedings 2022, Hamburg, 15. - 17. Nov. 2022}, booktitle = {SAMPE Europe Conference Proceedings 2022, Hamburg, 15. - 17. Nov. 2022}, year = {2022}, language = {en} } @article{HerzSchusserMuscatetal.2025, author = {Herz, Jonas and Schusser, Verena and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {Cold-Drawn Wood-Filled Polybutylene Succinate Macro-Fibers as a Reinforcing Material for Concrete}, series = {Polymers}, volume = {17}, journal = {Polymers}, number = {3}, publisher = {MDPI}, address = {Basel}, doi = {https://doi.org/10.3390/polym17030403}, pages = {21}, year = {2025}, abstract = {The corrosive behavior of steel reinforcements causes issues in the concrete industry. To overcome this issue, alternative noncorrosive reinforcements such as polymer fibers could be used. However, as environmental protection becomes more important, sustainability must also be considered in the solution. An alternative to polymers based on raw oil is bio-based polymers. This study investigates the suitability of polymer fibers produced from polybutylene succinate together with cellulose and wood fillers as concrete reinforcements. Different mixtures of polybutylene succinate, cellulose, and wood fillers were created, and fibers were produced using a multiple drawing process. The fibers were tested using tensile tests, a single-fiber pull-out test, contact angle measurements, reflected light microscopy, density measurements, and thermogravimetric analysis. The fillers were shown to decrease the mechanical properties as the particle size and filler amount increased, resulting in a reduction in Young's modulus and tensile strength of 55\% and 70\%, respectively, while adhesion to concrete increased with particle size from 0.31 ± 0.02 N/mm2 without filler to 0.90 ± 0.10 N/mm2 for the best-performing material combination. Reflected light microscopy images show changes in the fiber surface before and after pull-out. The fiber density decreased from 1.26 ± 0.05 g/cm3 to 0.91 ± 0.04 g/cm3 with an increasing filler amount and particle size for a compound with 10 weight percent of wood filler 1. The fiber thermal stability decreased slightly with the addition of filler. The greatest effect was a reduction in the temperature to ≈58 °C at 1\% weight loss when 10 weight percent of wood was added. This study proves the possibility of using bio-based materials as concrete reinforcements.}, language = {en} } @misc{KreyZenzWideraetal.2024, author = {Krey, Adrian and Zenz, Vitus and Widera, Karolin and List, Manuela and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {Reactive Extrusion of Lignocellulosic Biomass to Produce Biopolymer Monomers using High-Energy Radiation and Catalytic Acids}, series = {Proceedings of the 39th International Conference of the Polymer Processing Society (PPS-39)}, journal = {Proceedings of the 39th International Conference of the Polymer Processing Society (PPS-39)}, editor = {Ediciones Uniandes,}, doi = {https://doi.org/10.51573/Andes.PPS39.SS.BBB.6}, pages = {329 -- 337}, year = {2024}, abstract = {The increasing prevalence of bio-based and biodegradable plastics as an alternative to traditional plastics derived from crude oil is a noteworthy trend. Polybutylene succinate (PBS), a plastic produced from succinic acid, is among the promising materials for the future. However, the production of bio-based succinic acid through biotechnical processes in controlled environments presents challenges. This process leads to increased costs and is currently not economically competitive compared to crude oil-based succinic acid production. In addition to succinic acid, levulinic acid is another monomer produced in the same process. A novel approach to the digestion of biomass has been developed to address the issue of biotechnological production of bio-based platform chemicals. This innovative process employs microwave radiation, pressure, and temperature to convert wood residues into succinic acid and levulinic acid. Various catalyst concentrations and biomass ratios were tested in a batch process, with high-pressure liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC/MS) analyses revealing the formation of succinic acid, levulinic acid, formic acid, and 2 oxoglutaric acid. The results demonstrate that microwaves combined with a metal salt catalyst can be used to produce platform chemicals from lignocellulosic biomass. To further advance the continuous production of PBS, a twin-screw extruder was modified and adapted after the successful results obtained from the batch processes. This setup enables additional experiments to evaluate the transferability of batch process results to continuous reactions, facilitating the scale-up and economic viability of the overall PBS production process in the future.}, language = {en} } @inproceedings{HerzLorenzMuscatetal.2024, author = {Herz, Jonas and Lorenz, Katharina and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {Polymeric core-shell and mono-material fibers for concrete reinforcement}, series = {AIP Conference Proceedings}, volume = {3158}, booktitle = {AIP Conference Proceedings}, number = {1}, organization = {38th International Conference of the Polymer Processing Society (PPS-38)}, doi = {10.1063/5.0204946}, year = {2024}, abstract = {A reinforcement of concrete structures is needed because of the low tensile strength of concrete. Corrosion of the usually used steel reinforcments cause issues during time. Therfore, alternative reinforcements produced from non-corosive materials - like polymer fibers - become more interesting. A polymer fiber has to reach high mechanical properties and a good bonding ability to concrete. Both properties can be influenced by the selection of polymer and the used production process. Two polymers, polypropylene and aliphatic polyketone are tested within this study. First mono-material fibers of each material are produced and tested, later the materials are combined in a core-shell fiber. All fibers are produced by standard extrusion or coextrusion and a later drawing process. The mechanical properties are determined by tensile tests. The calculation of interfacial shear strength from single fiber pull-out tests allows an evaluation of the bonding ability. Additionally, fiber surface before and after pull-out is examined using reflected light microscopy. Contact angle measurements are done to evaluate possible influences of the surface energy and polarity. Density measurements are used to compare weight potential of the different mono-material and core-shell fibers. The results show good mechanical properties for all fiber materials. The interfacial shear strength is ≈ 2-3 times higher for fibers with polyketone compared to the ones with polypropylene at the fibers surface, which can be explained by higher surface energy and polarity of the polyketone compared to polypropylene and different surface deformation during pull-out. Lower densities are reached by fibers containing polypropylene.}, language = {en} } @techreport{StruebbeMuscatSigruener2022, author = {Str{\"u}bbe, Nicole and Muscat, Dirk and Sigr{\"u}ner, Michael}, title = {FHprofUnt 2016: Entwicklung maßgeschneiderter Polymerfasern zur Verbesserung der Lebensdauer und der mechanischen Eigenschaften von Beton (Conplasite) : Erfolgskontrollbericht FHprofUnt 2016: Projekt Conplasite : Berichtszeitraum: 01.08.2018-31.07.2021}, organization = {Technische Hochschule Rosenheim}, doi = {10.2314/KXP:185433476X}, year = {2022}, language = {de} } @article{SigruenerHueskenPirskawetzetal.2023, author = {Sigr{\"u}ner, Michael and H{\"u}sken, G{\"o}tz and Pirskawetz, Stephan and Herz, Jonas and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {Pull-out behavior of polymer fibers in concrete}, series = {Journal of Polymer Science}, volume = {61}, journal = {Journal of Polymer Science}, number = {21}, doi = {10.1002/pol.20230264}, pages = {2708 -- 2720}, year = {2023}, abstract = {The bond between polymer fibers and the surrounding cementitious matrix is essential for the development of concrete reinforcement. The single fiber pull-out test (SFPT) is the standard characterization technique for testing the bond strength. However, the different phases of debonding cannot be distinguished by the SFPT. This study investigates the debonding of different polymer fibers from the surrounding cementitious matrix with a modified SFPT and proposes methods to change the SFPT setup to generate more valuable information on the debonding mechanism. The SFPT was equipped with linear variable differential transformers (LVDT), digital image correlation (DIC) and acoustic emission (AE) analysis. The results demonstrate that the modified SFPT allows a better understanding of the different phases of debonding during fiber pull-out. Furthermore, bond strength values calculated by different methods reveal that the chemical bond of the investigated polymers is not different as reported by previous studies. Deformation measurements performed using LVDTs and DIC are suitable measuring techniques to characterize the debonding mechanism in SFPT. A correlation between recorded AE and debonding phases was not found.}, language = {en} } @inproceedings{SchusserSigruenerBogneretal.2023, author = {Schusser, Verena and Sigr{\"u}ner, Michael and Bogner, Stefan and Muscat, Dirk and Str{\"u}bbe, Nicole}, title = {Effect of Fillers on the Mechanical Properties of Drawn Polypropylene Fibers}, series = {International Conference on Composite Materials Belfast 2023 (ICCM 23), 30 July - 4 August 2023}, booktitle = {International Conference on Composite Materials Belfast 2023 (ICCM 23), 30 July - 4 August 2023}, year = {2023}, language = {en} }