Publications

Since 2004, PTG/e has supported many companies with its knowledge and expertise in the field of polymers. Some of our projects have resulted in patents and scientific publications. Information on these can be found on the Patents and Scientific Publications sections of this website. PTG/e news and other relevant news can be found in the News section.

Examples of projects we have performed in the past are highlighted in the Cases section.

Bollen van PTG Eindhoven.
Publications

Scanning Electron Microscopy (SEM) – Explained

Scanning Electron Microscopy is a technology that empowers researchers to delve into the intricate world of materials, providing valuable insights. The Scanning Electron Microscope can provide high resolution images of your material like you have never seen before. “Ready to elevate your project to new heights with Scanning Electron Microscopy? Contact us and find out how we can benefit your projects!” Watch the movie here!

Scanning Electron Microscopy

NEW THF Size Exclusion Chromatography (SEC) system!

We are excited to announce a new addition to our infrastructure with the integration of our new Size Exclusion Chromatography (SEC) system of Agilent. This new SEC system utilizes tetrahydrofuran (THF) as the mobile phase, combined with a highly sensitive Refractive Index (RI) detector.

This THF-SEC is meticulously calibrated using Polystyrene (PS) standards, empowering us to determine the molecular weight of polymers within a wide range, from 200 up to 400,000 Da.

Our team at PTG/e is highly experienced with polymers of all kinds. By expanding our existing SEC systems line-up with this THF-SEC, we can now tackle molecular weight determinations of almost any polymeric material with utmost efficiency and reliability.

Need to know the molecular weight of your materials? Contact us!

Size Exclusion Chromatography (SEC) this new SEC system utilizes tetrahydrofuran (THF).

PTG/e is a partner of the BatteryNL consortium!

More safe and longer-lasting battery: BatteryNL
We are proud to announce to be a partner in the Dutch BatteryNL consortium! As a partner, we join forces with a diverse range of companies, both small and multinational, as well as Dutch Universities.

The goal of the consortium is to develop the next generation of batteries within the next eight years. By focusing on a deeper understanding of material interfaces, and to unlock remarkable advancements in battery performance, safety, and longevity.

The Netherlands has long been at the forefront of innovation, and the BatteryNL consortium is an example of Dutch commitment to sustainable solutions. By bringing together a wide spectrum of expertise and perspectives, BatteryNL consortium creates the possibility to tackle the challenges of battery technology from multiple angles.

For more information about the BatteryNL consortium, please take a look on their website!

PTG Eindhoven member of the Dutch consortium BatteryNL.

NEW Climate chamber for tensile testing!

We are excited to announce a significant expansion of our testing capabilities at PTG/e! With the recent installation of our ESPEC SH-242 climate chamber, we are now able to offer you precise and reliable mechanical properties tests across a wide range of temperatures and humidity levels.

Key Features:
Temperature Range: Our climate chamber enables testing at temperatures ranging from -20 to +150 °C. This broad range ensures accurate simulation of diverse operating conditions, from freezing cold to scorching heat.

Humidity Range: We can also assess mechanical properties within a humidity range of 30 to 95 %RH, specifically at temperatures from +20 to +80 °C. This capability allows us to evaluate the impact of moisture on the performance of materials.

If you are looking for a partner to evaluate the mechanical properties of your materials, please feel free to reach out, to discuss how our enhanced testing capabilities can benefit your projects.

With our latest climate chamber, we can test in different temperature range and in humidity range. We are able to offer you a precise and reliable mechanical properties tests.

Peel the difference: Turning citrus peels into organic coatings

In recent years, there has been growing interest in exploring new and innovative ways to create sustainable and environmentally friendly paints. In collaboration with the Eindhoven University of Technology (TU/e) and a major player in the coating industry, PTG/e supported the development of an environmentally friendly way of generating polycarbonate coating resins by copolymerization of limonene oxide with carbon dioxide (CO2).

To explore more about this sustainable coating, let us first discuss some important aspects of powder coatings. Unlike conventional coatings like paints, which are films that are formed via the evaporation of a solvent, powder coatings typically are dry powders that are applied electrostatically and cured via temperature or with ultraviolet light and require no volatile components. Nowadays, these coatings are intensively used in industry to provide protection against aggressive environmental conditions and/or for decorative purposes. Some examples of powder-coated products can be seen in Figure 1. The binder or resin is the main constituent of a typical thermoset powder coating (TPC) and is the film-forming element of the product. It provides adhesion to a substrate, binds pigments and other additives together, and determines important properties such as durability, flexibility, and hardness. In addition, colors, additives, and fillers can be added to modify certain properties of the coating like gloss, opacity, and stability.

Figure 1: Examples of powder-coated applications which are applied for decorative and protective purposes, such as parts for the automotive industry and powder-coated metal objects like pipelines.

Several types of thermoset powders, derived from epoxies, acrylics, hydroxyls (polyester), and carboxyl(polyurethane) groups can be used in the synthesis of TPCs. Some of these types suffer from poor exterior durability or moderate chemical resistance. Therefore, an alternative could be a polycarbonate-based resin which is typically amorphous, and usually exhibits properties like high transparency and low UV absorption, particularly suitable for outdoor use. However, the downside of commercially synthesized polycarbonate is the use of phosgene (Cl2C=O), which is a highly toxic gas that requires serious environmental and safety considerations. The co-monomer bisphenol A (BPA) is also debated for its potential adverse health effects.

Limonene oxide is a potential biobased epoxide derived from limonene and could be a good alternative to phosgene / BPA. Limonene is a major component that can be found in the oil of citrus peels, like oranges. It is a colorless liquid that is often used as a flavoring agent in food manufacturing. Its abundance and its multiple functionalities make it an attractive, renewable building block for polymer synthesis. Via a chemical reaction that involves carbon dioxide (CO2), a fully recyclable poly(limonene carbonate) (PLC) can be synthesized, carrying functional groups that can be modified or crosslinked to introduce new functionalities such as antibacterial activity, hydrophilicity, and water solubility. This makes CO2, also known as the primary driver of climate change, a useful molecule that can be used as a monomer to create a sustainable polycarbonate powder coating. This pathway is shown schematically in Figure 2. As a result, this fully limonene-derived PLC has great potential as a TPC binder, which can deliver good exterior durability and chemical resistance. These two properties make this type of renewable binder a great alternative for the manufacturing of powder coatings, avoiding any concerning reactants.

Graphic about the oil from a citrus fruit can turn into a coating for organic paints.

Figure 2: Simplified overview that involves the reaction mechanism of a limonene-based coating. Here, first limonene is epoxidized to limonene oxide. The latter is used for the synthesis of poly(limonene carbonate) (PLC) in the presence of carbon dioxide. With the use of a crosslinking molecule (thiol-based) and radical initiator, under the influence of ultraviolet light, a crosslinked network (TEN) is formed via a thiol-ene reaction with the pendant isoprenyl groups of PLC and results in the formation of a thin layer on a particular surface.

Whether you’re looking to enhance material sustainability, develop new materials, or material research, our team has the knowledge, expertise, and state-of-the-art infrastructure to help you achieve your goals. And, with a large network within the TU/e, we’re able to tap into a wealth of knowledge and resources. Contact us to learn more about how we can help you!

For additional technical details about this topic, feel free to visit the main article via the following link: Limonene-derived polycarbonates as biobased UV-curable (powder) coating resins

Sustainable coating from citrus peels. PTG Eindhoven contributed in this research to create organic coatings.

Confocal Raman spectroscopy

Whenever a foreign material is confined between two extruded transparent films or a tiny particle is trapped within a coating matrix, it may ruin products with high optical requirements. It is not uncommon that our customers, often multi-layer film producers or coating companies, contact us to help find the root cause of such contaminations.

Confocal_Raman_spectroscopy_contaminationReaching the unreachable!
Confocal Raman spectroscopy is a highly suitable technique for this, as the laser beam can be focused on a particular spot beneath a material surface, shown in the schematic. We discuss the capabilities of this technique here in 2 demonstration examples.

 

Confocal_Raman_spectroscopy_eps1. Polyethylene bag
As a first example we have placed a closed polyethylene (LDPE) bag containing poly(ethylene terephthalate) (PET) granules directly under the confocal Raman apparatus. We performed a depth analysis through the bag into the granules, while continuously analyzing the material composition. A clear transition can be seen going from LDPE towards PET in the spectra below. This example also demonstrates another use case for this technique, in which a bag of unknown material could be analyzed without needing to risk opening the bag, as confocal Raman spectroscopy can be used to analyze the material right through the packaging.

Confocal_Raman_spectroscopy_zip_bag

Confocal Raman Aceton2. Glass vial with acetone
The same principle applies to unknown liquids inside a glass vial. In this example we placed a glass vial with acetone directly underneath the Raman microscope. The measurements can be performed through the glass barrier, while continuously analyzing the chemical composition of both the glass vial and the acetone. The spectra below clearly show the transition between the different materials

Confocal_Raman_spectroscopy_glasvial_acetone

Confocal Raman spectroscopy can be used to identify unknown substances, particularly when very detailed and local sample analysis is required. With this technique the chemical composition of particles with a particle size down to 1 μm can be analyzed. Moreover, these particles can be analyzed even if they are fully enclosed inside a matrix, as we have demonstrated in the examples.

Have you ever encountered small particulate matter trapped in your product without knowing its origin? Confocal Raman spectroscopy may be the answer. Please feel free to contact us to discuss the possibilities!

 

 

 

 

Confocal Raman Aceton