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6. Rheological Properties of Thermoplastic Polymers with Dissolved Gases for Foaming Applications

Author

Raps, Daniel, Hosseinabadi, Hossein Goodarzi, Heymann, Lutz, Köppl, Thomas, and Altstädt, Volker

Subjects
Condensed Matter - Materials Science, Condensed Matter - Other Condensed Matter, Physics - Applied Physics
Abstract

Understanding the concept of rheology in polymer melts with dissolved gases like CO2 is crucial in development of high quality polymer foams which are commonly manufactured by foam extrusion processes. The crystallization and rheological properties of the melt are significantly affected by the dissolved gas, which acts as a blowing agent and at the same time as a plasticizer. Moreover, the rheological properties of gas-loaded polymer melts influence on the efficient design of extrusion dies toward production of popular homogenous lightweight foams. This chapter will discuss common methods to measure these rheological properties with the example of a long-chain branched Polypropylene as a case study. To take into account the role of crystallization behavior under gas-loading into the process design, we describe a method to measure both rheology and crystallization in one experimental setup., Comment: 20 pages; The preprint of this book chapter was peer-reviewed and accepted for publication at the book entitled "Polymer Rheology" by InTechOpen publisher

Published
2018

20. Improving the flame‐retardant property of bottle‐grade PET foam made by reactive foam extrusion

Author

Bethke, Christian, Goedderz, Daniela, Weber, Lais, Standau, Tobias, Döring, Manfred, Altstädt, Volker, Bethke, Christian, Goedderz, Daniela, Weber, Lais, Standau, Tobias, Döring, Manfred, and Altstädt, Volker

Abstract

Upcycling of low intrinsic viscosity (IV) poly(ethylene terephthalate) (PET) grades, such as bottle‐ or recycled grades, by a reactive foam extrusion process, provides an appropriate alternative to high pricing, high IV grades commonly used for foaming applications. However, the drawback of bottle‐grade PET foams is its flame retardant (FR) performance. In this study, pyromellitic dianhydride was used as a chain extender to foam bottle‐grade PET. The influence of different FRs, containing halogenated (HFR) and four different phosphorous‐based types, on the processability and final foam properties was investigated. HFR showed better processability to achieve proper foams with fine morphology compared to P‐based FRs, where the FR content was adjusted between 2 and 5 wt%. However, HFR exhibited lower FR performance by cone calorimeter testing compared to the P‐based FRs and the commercial reference foam Kerdyn. Nonetheless, all of the FRs can only improve the time to ignition of the neat PET foams while the other values depend on the specific type of FR. In addition, all FR foams have improved mechanical properties more than twice in comparison to the neat PET foam.

Published
2024

21. Fire behavior of flame retarded sandwich structures containing PET foam cores and epoxy face sheets

Author

Bethke, Christian, Weber, Lais, Goedderz, Daniela, Standau, Tobias, Döring, Manfred, Altstädt, Volker, Bethke, Christian, Weber, Lais, Goedderz, Daniela, Standau, Tobias, Döring, Manfred, and Altstädt, Volker

Abstract

Within this work, the investigation on interactions of a phosphorus‐containing flame retardant (FR) DEPAl in epoxy face sheets and five different FRs in the PET‐foam core of a sandwich laminate on the fire behavior is focused. Fourteen different combinations of resin face sheets and PET foam cores are produced by vacuum assisted resin infusion (VARI). The combustion behavior of the sandwich laminates is tested by cone calorimetry. The time to ignition is lowered when a FR resin is used while the subsequent burning behavior is mainly influenced by the PET foam core. In order to evaluate the interactions of the flame retardants in the core and face sheet, a total improvement value (TIV) was set up which compares the performance related to the specific FR combinations. The highest TIV value (76%) indicating positive interactions with DEPAl was observed with a 2‐PSMP‐PET core, the lowest value (−2%) with a DEPZn‐PET core.

Published
2024

23. Foams

Author

Standau, Tobias, Altstädt, Volker, Karger-Kocsis, József, editor, and Bárány, Tamás, editor

Published
2019
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27. Evaluation of the potential of polybutylene terephthalate/Poly(phenylene oxide) blends for bead foam production.

Author

Standau, Tobias, Lindner, Kathrin, Altstädt, Volker, and Ruckdäschel, Holger

Subjects
POLYBUTYLENE terephthalate, FIREPROOFING, FOAM, BEAD making, POLYPHENYLENE oxide, CONTINUOUS processing, POLYMER blends, THERMAL stability
Abstract

An attempt to achieve bead foams that possess a higher thermal stability as well as an intrinsic flame retardancy is the use of suitable engineering polymers, such as the combination of polybutylene terephthalate (PBT) and poly(phenylene oxide) (PPE). However, both materials are very challenging to process – especially in the continuous foam extrusion coupled with an underwater granulator to obtain bead foams. In the recent study we show how the PBT/PPE blend morphology is affected by the PPE content and an epoxy-based chain extender (CE). Also, the morphologies of the bead foams with different blend compositions are shown. Stable processing was possible up to a PPE content of 10 wt.-%. The crystallization behavior changes by the addition of PPE and the lowest bulk density for the foamed beads was 130 kg/m3. This study aims to understand the melt behavior of PBT/PPE blends and to evaluate its potential for bead foam application in a continuous process. By using an epoxy-based chain extender the blend morphology can be influenced and a fine and homogeneous distribution of PPE in PBT can be achieved. The beads could be fused steamless with the rather novel radiofrequency technology. Trials with a cone calorimeter revealed a lesser (peak) heat release when burning compared to bead foams made from expanded polypropylene (EPP). [ABSTRACT FROM AUTHOR]

Published
2024
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28. Conclusion

Author

Lengsfeld, Hauke, primary, Lacalle, Javier, additional, Neumeyer, Thomas, additional, and Altstädt, Volker, additional

Published
2021
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29. Carbon Fibers

Author

Lengsfeld, Hauke, primary, Mainka, Hendrik, additional, and Altstädt, Volker, additional

Published
2021
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33. Composite Technology

Author

Lengsfeld, Hauke, primary, Lacalle, Javier, additional, Neumeyer, Thomas, additional, and Altstädt, Volker, additional

Published
2021
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36. Introduction

Author

Lengsfeld, Hauke, primary, Mainka, Hendrik, additional, and Altstädt, Volker, additional

Published
2021
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37. Contributors

Author

Akil, Hazizan Md, primary, Alhuthali, Abdullah, additional, Altstädt, Volker, additional, Alzeer, Mohammad I.M., additional, Avcıoğlu, Suna, additional, Bachtiar, Erik Valentine, additional, Bhoi, Neeraj Kumar, additional, Buldu, Merve, additional, Dang, Minh Phung, additional, Dao, Thanh-Phong, additional, Demleitner, Martin, additional, Dong, Yu, additional, Epaarachchi, Jayantha, additional, Fu, Kunkun, additional, Fu, Qiuni, additional, Giv, Ali Nemati, additional, Goh, Kheng Lim, additional, Häublein, Markus, additional, Henni, Abdellah, additional, Herath, Madhubhashitha, additional, Huang, Silu, additional, Jiang, Qian, additional, Jindal (Bhushan), Bharat, additional, Juon, Pang Hee, additional, Karar, Amina, additional, Kasal, Bohumil, additional, Kaya, Cengiz, additional, Kaya, Figen, additional, Khasraghi, Samaneh Salkhi, additional, Le, Hieu Giang, additional, Li, Yang, additional, Low, It-Meng, additional, MacKenzie, Kenneth J.D., additional, Nguyen, Duc Nam, additional, Nguyen, Tan Thang, additional, Noor Azman, Nurul Zahirah, additional, Nugroho, Wendy Triadji, additional, Pöhler, Christoph, additional, Pramanik, Alokesh, additional, Pratap, Saurabh, additional, Ramzun, Maizan Ramli, additional, Sabri, Fatin Nur Amirah Mohd, additional, Saeedipour, Hamid, additional, Shaikh, Faiz Uddin Ahmed, additional, Sharma, Sanjay, additional, Shojaei, Akbar, additional, Singh, Harpreet, additional, Sun, Min, additional, Tang, Youhong, additional, Wang, Bo, additional, Wu, Liwei, additional, Xu, X., additional, Yan, Libo, additional, Yang, Bin, additional, Zakaria, Muhammad Razlan, additional, Zeng, Qunfeng, additional, Zerrouki, Djamal, additional, Zhang, Zheng, additional, and Zhu, Huixin, additional

Published
2021
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40. Fazit der Autoren

Author

Lengsfeld, Hauke, primary, Lacalle, Javier, additional, Neumeyer, Thomas, additional, and Altstädt, Volker, additional

Published
2020
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41. Prüfung von Prepregs

Author

Lengsfeld, Hauke, primary, Lacalle, Javier, additional, Neumeyer, Thomas, additional, and Altstädt, Volker, additional

Published
2020
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42. Introduction

Author

Lengsfeld, Hauke, primary, Mainka, Hendrik, additional, and Altstädt, Volker, additional

Published
2020
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43. Carbon Fibers

Author

Lengsfeld, Hauke, primary, Mainka, Hendrik, additional, and Altstädt, Volker, additional

Published
2020
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49. Faserverbundwerkstoffe

Author

Lengsfeld, Hauke, primary, Lacalle, Javier, additional, Neumeyer, Thomas, additional, and Altstädt, Volker, additional

Published
2020
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