Study Finds PFAS Chemicals May be Linked to Increased Risk of Cardiovascular Disease

DZNE researchers provide evidence that traces of the widely used PFAS chemicals in human blood are associated with unfavorable lipid profiles and thus with an increased risk of cardiovascular disease.

The findings are based on data from more than 2,500 adults from Bonn and the Dutch municipality of Leiderdorp. PFAS were detected in the blood of nearly all study participants. The study results were published in the renowned scientific journal “Exposure and Health”.

Effects are More Pronounced in Younger Population:

It is estimated that more than 10,000 different per- and polyfluoroalkyl substances (PFAS) have been developed since their invention in the 1950s. They are used in thousands of products ranging from cosmetics and dental floss to pan coatings and firefighting foams because of their water-, fat- and dirt-repellent properties. In addition to their basic chemical structure, PFASs have another thing in common: they are virtually non-degradable. They enter the human food chain primarily through groundwater.

The findings of the Bonn researchers are the latest contribution to the current debate on the effect of PFAS on human health. “We see clear signs of a harmful effect of PFAS on health. And we have found that at the same PFAS concentration in the blood, the negative effects are more pronounced in younger subjects than in older ones,” says prof. Dr. Monique Breteler, director of Population Health Sciences at DZNE. The results of the current study also suggest that even relatively low PFAS concentrations in the blood are associated with unfavorable blood lipid profiles.

“Our data shows a statistically significant correlation between PFAS in the blood and harmful blood lipids linked to cardiovascular risk. The higher the PFAS level, the higher the concentration of these lipids. Taken strictly, this is not yet a proof that PFAS chemicals cause the unfavorable blood lipid profiles. However, the close correlation supports this suspicion. It is a strong argument for stricter regulation of PFAS in order to protect health,” says the Bonn researcher. Strikingly, PFAS could be detected in the blood of almost all test subjects. Which means you cannot escape these chemicals. “Even if we don’t see an immediate health threat for the study participants we examined, the situation is still worrying. In the long term, the increased risk may very well have a negative impact on the heart and cardiovascular system,” says Breteler.

Blood Samples from Bonn and the Netherlands:

The current study was based on DZNE’s “Rhineland Study” – a population-based health study in the Bonn urban area – and the so-called NEO study from the Netherlands (“Netherlands Epidemiology of Obesity study”). Researchers from the DZNE collaborated with experts from the Leiden University Medical Center in the Netherlands. Blood samples from more than 2,500 men and women between the ages of 30 and 89 were included in the analyses. State-of-the-art technology was used. "The technology to analyze blood samples with the accuracy required for our research has only become available in the last few years," says DZNE scientist Elvire Landstra. Together with a colleague from Leiden, she is the first author of the current publication.

Proven Connection Between PFAS and Unfavorable Lipid Profiles

The blood samples were analyzed in detail using a sophisticated method known as mass spectrometry. In their analysis, the researchers focused on three of the most common types of PFAS – PFOA, PFOS and PFHxS – and also determined the concentration of 224 blood lipids, metabolites and amino acids. “With this ‘untargeted approach’ – an intentionally broad approach without a preconceived target – we were able to prove the connection between the PFAS concentration and a problematic profile of fatty substances, so-called lipids. These include the well-known cholesterol and various other blood lipids that are known to be risk factors for cardiovascular disease,” says Elvire Landstra.

No significant differences were found between the samples from Bonn and Leiderdorp. “Our study is the most detailed on this topic to date and the one with the largest database. Previous studies had already suggested a correlation between PFAS and unhealthy blood lipids, but this link had never been as clear as in our study.”

Future studies could focus on specific areas of the body, the Bonn researchers suggest. “We looked at the blood levels. In a next step, it would make sense to investigate the occurrence of PFAS in individual organs,” Monique Breteler says.

Source: DZNE/Omnexus.specialchem

Azelis Secures Distribution of LANXESS’ Flame Retardants in the U.S. Market

Azelis announces it has been appointed the exclusive distributor in the U.S. of LANXESS polymer additives phosphorous flame retardants. It includes the Disflamoll® and Levagard® product lines.

Azelis’ CASE technical expertise and application labs in the Americas region will be leveraged to grow the market and support customers' needs. The commercial partnership is effective as of April 1, 2024.

Building Additive’s Portfolio for CASE Market:

LANXESS Polymer Additives is a leading supplier of flame-retardant additives for multiple industries, including construction, electrical and electronics, and transportation. Fire represents a significant risk to both life and property.

LANXESS flame retardants are innovative polymer additives that provide substantially increased fire protection when added to rubber and plastic materials, such as flexible PU, rigid PU foam formulations and PVC. They offer superior low flammability, low flame propagation, and low smoke density and are designed to meet applicable regulations and standards and ensure compliance with the safety requirements of various industries.

The LANXESS Polymer Additives phosphorous flame-retardant portfolio includes the Amgard®, Disflamoll®, Levagard®, and Reofos® extended product lines, as well Emerald Innovation® NH-1. Azelis also represents the brominated line of flame-retardants Firemaster®, PHT4® and PHT4 Diol®, BA59P®, BC 58®, PDBS-80®, and Emerald Innovation 3000®.

Shiona Stewart, managing director, Azelis, CASE US comments, “The addition of LANXESS polymer additive's phosphorus flame retardants is a direct result of the hard work and positive results we have delivered. By adding Disflamoll® and Levagard® products, this continues to build out our additive’s portfolio for the CASE market. Azelis has had a long and successful commercial relationship with LANXESS, and we are excited to expand our collaboration with this new set of high-performance additives. Our application labs and chemists will provide technical expertise and innovative solutions for our customers as they seek to develop new product applications.”

Source: Azelis/Lanxess/specialchem

Today's KNOWLEDGE Share:Carbon Fiber Monocoque

Today's KNOWLEDGE Share

Congratulations Oxford Brookes Racing team.

I’m very proud to present the Oxford Brookes Racing OBR24 Carbon Fiber Monocoque. Our Composites Team has shown exceptional dedication this year, undertaking a redesign of the laminate and internals of the chassis, manufacturing new moulds, and introducing a three-stage cure process to elevate the quality of the chassis. Thanks to these advancements, we managed to cut the monocoque weight by 26% and significantly improve the manufacturing quality and controllability. We were also able to deliver the project on time, and an entire month ahead of last year’s timeline. These substantial improvements to one of OBR’s largest and most complex components will help the team increase testing time, decrease our lap time, and maximize our score at FSUK and FSCz this year.

Words can’t describe how proud I am of this team for pulling together and persevering through the long days and nights on this project. To everyone involved, thank you; you’re the ones that truly made this happen! I’d also like to thank Silverstone Composites for supporting our Composites manufacturing efforts. This wouldn’t be possible without your support!

source:Garrett Perry-Oxford Brookes Racing

Today's KNOWLEDGE Share:Mositure Absoption

Today's KNOWLEDGE Share

So, like most of us in Europe, you enjoyed an unusually warm, sunny and dry weather spell this summer.

Now you are back to work and dive again into your plastic part associated with the problems.

The part shown is made of nylon. Nylons are very decent materials for mechanical properties, except they can be very sensitive to some environmental aspects.

In dry weather, PA66 will lose moisture, which acts as a very efficient plasticizer, making the material much more brittle. If such part dries out in the sun, the UV radiation will slowly break down the polymer chains and also contribute to the material becoming more and more brittle over time. Contrary to the moisture effect, UV degradation is irreversible. Moisture absorbed by nylons also translates into some "swell". Look at it as "negative shrinkage". So if nylon dries out around an overmolded insert, the tensile stress becomes much larger until it could trigger part failure, possibly at a weak point like a weld-line.

Because the glass transition temperature is very moisture sensitive, in a dry spell, nylon Yield and Modulus will go up with the increasing Tg, further enhancing the brittle failure risk of this part.

So summertime is great for us to recharge our batteries, but it could kill some of our parts if we are not prepared !

source:Vito leo

Today's KNOWLEDGE Share:Annealing

Today's KNOWLEDGE Share

Different types of annealing heat treatments:

#Annealing is a process in which metal is heated and then allowed to cool, to restore its original ductility and reduce hardness and brittleness.

Annealing Types -

Stress Relief Annealing:

Aims to alleviate internal stresses within the metal component, typically addressing stresses caused by uneven cooling post-casting. This involves heating to a point sufficient for dislocation removal within the metal’s crystal lattice, followed by slow cooling in still air, without phase transitions.

Isothermal Annealing:

Utilizes detailed knowledge of an alloy’s temperature-time diagrams to enhance machinability, maintaining the alloy above the recrystallization temperature for a period, then rapidly reducing the temperature to a lower, constant level to control austenite decomposition.

Diffusion Annealing:

Aims to equalize the alloy mix's chemical composition, erasing segregation from casting. For steels, it involves merging iron and carbide at a high temperature above the upper critical temperature for several hours, often necessitating further annealing for desired grain production.

Complete Annealing:

Involves heating above the upper critical temperature and controlled cooling to attain a specific microstructure, demanding a thorough understanding of the alloy’s transformation diagrams.

Spherification Annealing:

Focuses on forming spheroid structures within the alloy, especially forming carbide spheroids within ferrite for high-carbon steels to improve machinability or facilitate cold forming.

Recrystallization Annealing:

Promotes the formation of new, undeformed grains, replacing previously deformed grains without phase change, usually applied to cold-worked steels to restore ductility and control grain structure.

Annealing functions by enabling atoms in the steel structure to move, provided with energy by temperature elevation. This atom migration resolves dislocations and internal stresses, potentially forming more grains if the temperature is adequately high.

Applications

Reversing Work Hardening: Restoring original mechanical properties after cold working.

Reducing Weld Solidification: Improving physical properties around welds by reducing precipitate solidification, thereby enhancing weld zone homogeneity and mechanical characteristics.

Enhancing Electrical Conductivity: Improving electrical and magnetic properties through dislocation reduction and crystal lattice restoration.

Annealing stages

Recovery Stage: Elevating metal temperature to energize atoms, remove dislocations, relieve stresses, and restore ductility.

Recrystallization Stage: Reorganizing crystal structure and forming new grain structure free of pre-existing stresses, returning the material to its pre-worked state.

Grain Growth Stage: Controlling new grain development and growth during cooling, dependent on cooling conditions.

source:Metallurgical Engineering

IMDEA Materials demonstrates breakthrough recyclability of carbon nanotube sheets

Researchers have demonstrated for the first time that high-performance carbon nanotube sheets and textiles can be recycled at the macroscopic scale with nearly 100% retention of mechanical and electrical properties.

Researchers from IMDEA Materials Institute have published groundbreaking work demonstrating, for the first time, the ability to recycle high-performance carbon nanotube (CNT) sheets while preserving their shape, structural alignment, mechanical and electrical properties, and intrinsic flexibility. 

The paper, Network structure enabling re-use and near full property retention in CNT sheets recycled from thermoset composites, was recently published in a special issue of prestigious journal Carbon.

It represents a significant advance in the field of sustainable nanostructured materials and in the viability of fibres, sheets, and textiles made of carbon nanotubes to play a key role in the future green energy transition.

“This research represents a crucial step towards manufacturing and usage of sustainable and recyclable CNT fibres and sheets,” explained Dr. Anastasiia Mikhalchan, Senior Research Associate at IMDEA Materials and Co-PI of the project.

“These will be able to displace widespread CO2-intensive materials, such as conventional carbon fibres and some metals like copper, decreasing our future CO2 emissions footprint”.

“Our work demonstrates that high-performance materials made from carbon nanotubes are recyclable and can be reused in the same application as structural reinforcement or electrical conductors. This is due to the fact that neither their continuity, alignment and mechanical properties nor their conductivity is affected by recycling”.

The work utilizes carbon nanotubes that are rapidly grown and directly assembled into freestanding network materials by means of floating catalyst chemical vapour deposition (FCCVD) synthesis process.

IMDEA Materials Institute is one of the world leaders in the field and is currently the only research centre in the European Union capable of synthesising high-quality nanotube macromaterials.

These CNT fibres and sheets possess high structural toughness and flexibility as well as high mechanical, electrical and thermal properties. This enables their usage in structural reinforcement in composite laminates, as well as printable strain/stress sensors, electrical conductors, and flexible battery anodes, among other applications.

In addition to the demonstrated recyclability in the macroscopic sheet-format, the researchers envision the future possibility of next-level disintegration of the recycled sheets to their building blocks – CNTs – in liquid crystalline solutions, which could then be re-spun into a new high-quality fibre.

“This prospective is similar to breaking down a LEGO model into its individual bricks, and then re-building the original model with the same shape, robustness, and quality,” explained Dr. Mikhalchan.

“This is never possible with conventional carbon fibres because their crystalline structure is formed by fused crystallites in the graphitisation process, so they cannot be “broken down” into individual crystallites and re-graphitized again into a continuous fibre filament”.

“In contrast, carbon nanotubes are capable of dissolution in superacids and can be re-spun into a fibre, which is a matter of future confirmation”.  

This pioneering work is supported by the Rice University-led Carbon Hub Initiative. IMDEA Materials’ Multifunctional Nanocomposite research group, led by Dr Juan J. Vilatela, is an active member of the initiative, alongside some of the world’s most prestigious research institutions such as the University of Cambridge, Stanford University, Georgia Tech, and MIT.

Carbon Hub is targeting a zero emission future, and together with the stakeholders from the oil&gas industry, pursue the new paradigm of sustainable co-production of clean hydrogen and advanced carbon nanostructured materials from natural gas and oil.

Instead of burning hydrocarbons to generate energy while releasing gigatons of CO2 into the atmosphere, the Initiative proposes the innovative transformation of hydrocarbons into high-performance value added nanocarbons (such as CNT fibres and sheets) with cogenerating net clean energy as (turquoise) hydrogen.

Presently, the world’s CNT production capacity is in the order of 10 kt/year, a rate which is increasing at roughly 30% annually. However, this could accelerate to the megatone scale if the Carbon Hub efforts are successful and nanocarbons start displacing metals.

The work demonstrated by IMDEA Materials researchers is another milestone in this trajectory, confirming that value-added carbon nanotube materials are, by their nature, recyclable and can be re-used in the same application.

Their network structure and inherent toughness, similar to ductile polymers, makes them extremely tolerant to defects and therefore suitable for re-use and re-processing as high added value materials.

“Even three years ago, there was little interest in recycling CNT-based materials, but now it is becoming a far more relevant topic”, Dr. Mikhalchan stated. “We believe our research will stimulate the scale-up of manufacturing high-performance CNT materials and their faster adoption by industry, knowing that such materials offer sustainability and recyclability and are capable of reducing component weight and industry’s CO2 footprint”.

Those behind the recent breakthrough, alongside Dr. Mikhalchan, include former IMDEA Materials intern Sergio Ramos Lozano, IMDEA Materials PhD student Dr. Andrea Fernández Gorgojo, Prof. Carlos González and Dr. Vilatela.

source:www.materials.imdea.org/jeccomposites.com

Today's KNOWLEDGE Share : Key features of PPE and modified PPE resins

Today's KNOWLEDGE Share

Key features of PPE and modified PPE resins

Heat resistance:

Pure PPE resin has a glass transition point of approximately 210°C. Modified PPE resins exhibit a range of behavior depending on the partner material used to form the alloy: from high-fluidity grades with heat deflection temperatures below 100°C to highly heat-resistant grades with heat deflection temperatures above 200°C.

• Flame retardance:

The oxygen index (a measure of the quantity of oxygen needed for combustion) for pure PPE resin is 28, a high value indicating that it is relatively easy to make this material flame-retardant. Asahi Kasei's lineup of modified PPE resins includes several grades with excellent flame retardance at the UL94 V-0 level.

• Low specific gravity:

PPE resin is a lightweight material whose specific gravity just 1.06—is the lowest of all engineering plastics.

• Electrical insulation:

PPE resins have high volumetric resistivity, making these materials excellent electrical insulators. The outstanding tracking resistance and other favorable electrical properties of PPE resins make these materials a common choice for a wide variety of products.

• Low water absorption:

Pure PPE resin is a low-water-absorption material. Modified PPE resins retain this advantage, exhibiting minimal change in physical properties and minimal dimensional variation upon water absorption.

• Hydrolysis resistance:

Modified PPE resins boast excellent heat resistance, and the absence of esters or amides from their chemical structures also ensures excellent resistance to warm water and to hydrolysis.

• Resistance to acids and alkalis:

A characteristic feature of modified PPE resins is their strong resistance to acids and alkalis.

• Low dielectric permittivity and low dielectric loss tangent:

PPE resin exhibits low dielectric permittivity and low dielectric loss tangent over a wide range of frequencies and these properties remain largely unchanged across variations in operating temperature and humidity. The low transmission losses achievable with modified PPE resins make these materials a common choice for components of information and communication systems.

• Low linear-expansion coefficient:

PPE resin exhibits the lowest linear-expansion coefficient of all engineering plastics, minimizing shrinkage during molding and ensuring excellent dimensional stability and dimensional precision.

source:Asahi Kasei