Matthias Deckert

• Professor
• Professor at Esslingen University of Applied Sciences

Liquid silicone rubber (LSR) has gained considerable importance in various branches of industry due to its unique properties such as high heat resistance, chemical resistance and excellent aging properties. LSR is used in a wide range of applications, from seals to medical devices and food components. The LSR injection molding process enables preci...

The injection molding industry has to face various challenges, such as the shortage of skilled workers and regulatory requirements like the increasing use of recycled materials. These challenges can be overcome, for example, with artificial intelligence (AI) that predicts component quality and suggests machine control parameters. This could drastic...

Halting climate change represents the most significant challenge facing humanity in the current century. With the escalating challenges caused by global warming, reducing greenhouse gas emissions through effective recycling strategies for plastic components has become imperative. Besides the large plastic waste producers, niche products also offer...

The integration of titanium dioxide into polymers to confer antibacterial properties could be a promising field in materials science, particularly within the field of additive manufacturing. This study investigates the impact of varying concentrations, of titanium dioxide in a polyamide 12 matrix on the UV resistance and mechanical properties of sp...

The processing of optical liquid silicone rubber (LSR) formulations is associated with significant quality issues and high rejection rates. Often, the quality issues can be attributed to deviations in LSR dosing. To address these issues, specific mixing ratios of components A and B that deviate from the standard 1:1 ratio were intentionally created...

Climate change is one of the significant challenges of the 21st century. To achieve climate goals a change in plastic waste management needs to be implemented. This research examines the potential of thermo‐mechanical recycling of plastic waste, focusing on agricultural binding twines made from polypropylene. Old binding twines from agriculture wer...

Liquid silicone rubber (LSR) is characterized by a wide range of advantageous properties and is therefore used in many branches and industries. However, the material is difficult to recycle due to the non‐reversible cross‐linking reaction. A promising approach to recycle the already cross‐linked (post‐industrial) waste is the mechanical recycling o...

Antibacterial properties of components are increasingly becoming an important challenge in material development especially in polymer technology. A well‐known additive with which an antibacterial effect can be achieved is the metal oxide titanium dioxide. The aim of this research work was to investigate possible influences on the flexural propertie...

Effects of global warming can now be seen and felt more than ever, especially in the Alps. The Alps and other mountains are massively affected by glacier retreat and permafrost degradation. Sustainable production, widespread recycling and a closed-loop product life cycle to reduce greenhouse gas emissions are becoming a major concern. This study se...

With the help of computational fluid dynamics (CFD) simulations a nozzle system (top nozzle system) for hot gas welding, which encloses the weld seam during heating, was developed. The significantly more controlled flow behavior of the hot gas improves the processing window, increases the reproducibility and achieves a more efficient heating of the...

A new project is proposed about the development and manufacturing of innovative, slim lenses for eyeglasses and VR-glasses, with nature replicated properties, by utilizing a two-stage injection molding process. The primary objective is to achieve material, energy and timesaving as well as giving the wearer of lenses a better experience in comfort....

An AI-based injection molding assistant is being developed to improve the injection molding process. On the one hand, it is intended to predict the quality of the components and, on the other hand, to suggest machine control parameters in the event of deteriorating quality, which are meant to improve the component quality again. For this purpose, b...

Hot gas welding is a joining process that melts the thermoplastic polymer without contact by convection heating and has been increasingly investigated and developed in recent years. The reason is the absence of the formation of particles during the heating process of the polymer, e.g. in friction welding or the adhesion of polymer melt in hot plate...

An immersing nozzle system (top nozzle) which was developed for hot gas welding with the aid of CFD simulations encloses the weld during the heating operation and permits the joining of welds with inclination angles up to 45°. The investigations on a series-capable hot gas welding installation with plate-shaped test specimens made of PA6-GF30 show...

Antimicrobial properties of plastic components are an important part of polymer engineering. One commonly used additive with an antibacterial effect is titanium dioxide. The aim of this study is to investigate the influences on the mechanical properties resulting from the addition of titanium dioxide as an antimicrobial additive and the processing...

A nozzle system (top nozzle system) for hot gas welding, which encloses the weld seam during heating, was developed with the help of computational fluid dynamics (CFD) simulations. The significantly more controlled flow behavior of the hot gas improves the processing window, increases the reproducibility and achieves a significantly more efficient...

An initiation of adhesion between standard thermoplastic injection molding materials and non-adhesion-modified optical grade liquid silicone rubber (LSR) was achieved via physical surface treatments. In this study, peel test specimens of thermoplastic and liquid silicone rubber were produced in a two-component injection mold. Both surface treatment...

The processing of liquid silicone rubber (LSR) in the injection molding process is becoming increasingly important. The reasons for this are its outstanding properties and economic processability. The functionalization of surfaces through nano- or microstructures introduced directly in the injection mold opens up new fields of application. For exam...

Series production of the future is facing the challenge of ever higher demands for individualised and complex products. Thus additive manufacturing is one of the key technologies to meet these demands. A major challenge in the selective laser sintering process is the reuse of the powder leftover after the building process as only 5–20% of the powde...

Global warming has increasingly drastic consequences, especially in the Alps but also in the rest of the world. In order to reduce greenhouse gases, widespread recycling of plastic waste is becoming an essential necessity. This research investigates a possible recycling process for old climbing ropes made out of polyamide 6. Old climbing ropes were...

The processing of liquid silicone rubber (LSR) in the injection molding process to molded parts offers high economic potential due to its great scalability. Unlike the well‐researched and understood injection molding process of thermoplastics, LSR still lacks basic process knowledge. The cavity pressure curve shows a completely different pattern, a...

The use of cross-linking polymers such as liquid silicone rubber (LSR) can replicate serviceable surfaces with nano-and microstructures via the injection molding process. Laser ablation can be used to introduce microstructures into molding tools, while nanostructures are generated via PVD coating processes on the tools. This is why nanostructures a...

With the help of CFD simulations, a nozzle system (top nozzle) for hot gas welding is developed , which encloses the weld seam during heating. The significantly more controlled flow behavior of the hot gas improves the processing window, increases the reproducibility and achieves a significantly more efficient heating time of the polymer weld seam....

Additive manufacturing is one of the key technologies for the future production of complex and individualised components. One of the most challenging questions to minimize the production cost is the reuse of the powder leftover after the building process. This study investigates the influence on the mechanical properties when reusing the leftover p...

The standard hot gas welding process uses a nozzle system consisting of multiple round tubes. With the top nozzle system, the weld seam is encapsulated to minimize heat loss and allow better control of the hot gas flow. This significantly reduces the required heating time of the polymer. Temperature measurements and welding tests with plates of var...

Aktuell wird zum Heißgasschweißen standardmäßig ein Düsensystem aus aneinander gereihten Röhrchen (Rund-Düse) verwendet. Die Rund-Düse erwärmt den Kunststoff durch eine Prallströmung. Dadurch entstehen die kraterförmigen, aus der Praxis bekannten, Strukturen auf der Kunststoffoberfläche unter jeder einzelnen Düse. Bei dieser Düsen-Art entstehen, ne...

Kommt beim Heißgasschweißen anstatt einer Rund- eine Aufsatzdüse zum Einsatz, ergeben sich bei der Verarbeitung eine Reihe von Vorteilen. Dazu zählen ein breites Prozessfenster, kurze Erwärmungszeiten und die Einsparung von Ressourcen. Die neue Entwicklungsstufe des Heißgasschweißprozesses ermöglicht darüber hinaus erst das prozesssichere Fügen von...

Aktuell wird zum Heißgasschweißen standardmäßig eine Düse aus aneinander gereihten runden Röhrchen (Rund-Düse) verwendet. Eine neu entwickelte Düse (Aufsatz-Düse), welche die Schweißnaht beim Erwärmen umschließt, ermöglicht es beim Heißgasschweißen, die Erwärmungszeit des Kunststoffes um bis zu 60 % zu reduzieren. Für PA66-GF35 z.B. kann die Erwärm...

Processing of liquid silicone rubber (LSR) in the injection molding process has a high economic potential. Since there are some fundamental differences compared to classical thermoplastic injection molding, up to now there is a lack of well‐founded knowledge of the process which allows an estimation of the cycle time. Because, in addition to revers...

Für die Verarbeitung von thermoplastischen Polymeren im Spritzgießprozess ist die Wahl der Werkzeugwandtemperatur entscheidend für die Formteileigenschaften und die optimale Zykluszeit. Das Spritzgießwerkzeug wird standardmäßig bei einer konstanten Werkzeugwandtemperatur betrieben, die bei speziellen Anwendungen, wie zum Beispiel die Abformung von...

This work focuses on the mechanical behavior of micro surface structures (molded both in the injection and reaction injection processes) in scratch tests using rounded cone indenters of different sizes. The interest in polymeric micro surface structures has increased in diagnostics, mass storage or optical fields as well as in the production of min...

In this paper the replication qualities of periodically and randomly arranged micro-features molded in the injection molding process and their effects on surface properties are studied. The features are molded in PC, PMMA and PP at different mold wall temperatures in order to point out the necessity and profitability of a variotherm mold wall tempe...

The injection molding of micro-structures is a promising mass-production method for a broad range of materials. However, the replication quality of these structures depends significantly on the heat flow during the filling stage. In this paper, the filling and heat transfer of v-groove and random structures below 5μm is investigated with the help o...