#fluoropolymers

Fluoropolymers have become an integral part of modern society, both in industrial and consumer applications. When these high-performance materials reach the end of their useful life, they can end up in both industrial and household waste. Working with international partners, researchers at the Karlsruhe Institute of Technology (KIT) analyzed the contribution of waste incineration of fluoropolymers to the release of low-molecular, non-polymeric fluorinated compounds. Their experiments with the BRENDA incineration facility at KIT showed nearly complete destruction of fluoropolymers in combustion at the temperatures and residence times typical of European incinerators. The study has been published in the journal Chemosphere. In contrast to fluoropolymers, which are also referred to as "polymeric PFAS" and are considered to be non-mobile and non-bioaccumulative, used e.g. in medical products, semiconductors, aerospace, automotive and chemical processing, "low-molecular PFAS" are integrated in a wide range of dispersive consumer applications. They are found, for instance, as water-repellent impregnation in textiles, garments, paper (pizza boxes, burger boxes, baking backpaper). The PFAS substance group includes approx. 10,000 substances, whereby the fluoropolymers only represent a small subgroup of 38 substances.

Fluoropolymers are macromolecules made up of carbon and fluoride which, due to their properties, tend to be used as non-stick and anticorrosive coatings on a wide range of material. Products in the clothing, graphic, chemical and car industries as well as different metal molds and kitchen utensils need fluoropolymers for their coatings and to improve their features regarding sticking and resisting corrosion.

These kinds of coatings tend to be quite effective due to their characteristics. They resist abrasion, they behave stably at high temperatures and their structure is not affected by most chemical agents. Nevertheless, despite their resistance, they wear away with use like any other kind of material. In order to deal with this issue, the alternative to replacing the whole piece, often times a very expensive solution, is removing the coating, taking out any impurities and taking off any parts that are attached, and recoating it.

Here is where the merits of fluoropolymers become a problem. Since they are extremely resistant and chemically inert materials, they adhere to a surface and do not come off easily. To deal with this, the Manufacturing Processes Engineering research group at the University of Cordoba has validated a new method to take off these kinds of coatings using a laser technique.

New methods to create microfluidic devices with fluoropolymers

Currently, a wide range of applications has been demonstrated using microfluidic devices made of silicone rubbers (such as polydimethylsiloxane (PDMS)), including materials syntheses, separation and sorting, diagnostics and bioanalysis. The reason for the popularity of PDMS in academic laboratories is the simplicity of the fabrication and well-characterised properties of PDMS. However, PDMS are not compatible with strong organic solvents; they quickly swell silicone-based materials. To this end, microfluidic channels possessing chemical and solvent compatibility would be desirable.

A research team from the Singapore University of Technology and Design (SUTD), led by Assistant Professor Michinao Hashimoto, developed a simple method to fabricate microchannels using fluoropolymers -- a general class of polymers including TeflonTM that are highly inert against the exposure to chemicals and solvents. The research group applied xurography (i.e. a method of digital fabrication to cut films with a motion-controlled razor blade to create stencils) to cut films of fluoropolymers and heat-press to from microchannels. It takes less than 1 hour to make microchannels from designing to assembling using this method.

Nanostructure boosts stability of organic thin-film transistors

Improved design uses a nanostructured gate dielectric

A nanostructured gate dielectric may have addressed the most significant obstacle to expanding the use of organic semiconductors for thin-film transistors. The structure, composed of a fluoropolymer layer followed by a nanolaminate made from two metal oxide materials, serves as gate dielectric and simultaneously protects the organic semiconductor -- which had previously been vulnerable to damage from the ambient environment -- and enables the transistors to operate with unprecedented stability.

The new structure gives thin-film transistors stability comparable to those made with inorganic materials, allowing them to operate in ambient conditions -- even underwater. Organic thin-film transistors can be made inexpensively at low temperature on a variety of flexible substrates using techniques such as inkjet printing, potentially opening new applications that take advantage of simple, additive fabrication processes.

"We have now proven a geometry that yields lifetime performance that for the first time establish that organic circuits can be as stable as devices produced with conventional inorganic technologies," said Bernard Kippelen, the Joseph M. Pettit professor in Georgia Tech's School of Electrical and Computer Engineering (ECE) and director of Georgia Tech's Center for Organic Photonics and Electronics (COPE). "This could be the tipping point for organic thin-film transistors, addressing long-standing concerns about the stability of organic-based printable devices."

Transparent coatings for everyday applications

Water- and dirt-repellent sportswear and outdoor clothing, or anti-fog windshields – there are many everyday products that can profit from highly hydrophobic coatings. For such coatings, researchers led by Dr. Bastian E. Rapp at Karlsruhe Institute of Technology (KIT) have created Fluoropor, a material that is both transparent and abrasion-resistant and that consists of a fluorinated polymer foam with continuous nano/micro-structure. Fluoropor is presented in Nature Scientific Reports.

Water droplets run off the leaf surface: In nature, this phenomenon is mainly known from lotus plants. Researchers imitate this lotus effect by means of superhydrophobic i.e., highly water-repellent, surfaces. At KIT, the team of Dr. Bastian E. Rapp at the Institute of Microstructure Technology (IMT) develops a new class of such materials called Fluoropor. The researchers combine the properties of fluoropolymers i.e., plastics with a degree of fluorination, with the roughness known from lotus leaves. In this way, they obtain surfaces that are both oil- and water-repellent. The new materials are characterized by a high chemical and thermal stability. Together with researchers from the Institute for Applied Materials – Computational Materials Science (IAM-CMS), the researchers in Dr. Rapp's junior research group NeptunLab succeeded for the first time in developing a fluorinated polymer foam which, in addition, is transparent and insensitive to abrasion. This material, called Fluoropor, is introduced in Nature Scientific Reports.

(via Global Fluoropolymers Market | PTFE, PVDF, FEP, ETFE, PCTFE)

(via Fluorinated Ethylene Propylene (FEP) Market | Trends & Forecast 2025-2032)

(via Polytetrafluoroethylene (PTFE) Market | Trends & Forecast 2025-2032)