Today's KNOWLEDGE Share : Texas Attorney General Ken Paxton sues companies over “forever chemicals:

Today's KNOWLEDGE Share

Texas Attorney General Ken Paxton filed a lawsuit Wednesday against chemical giants 3M and DuPont, accusing them of decades-long misrepresentations and omissions regarding the safety of PFAS, or “forever chemicals,” sold for use in countless consumer products.

These products, sold under brand names such as Teflon, Stainmaster, and Scotchgard, have been staples in households across the nation despite mounting evidence that they contain chemicals that are harmful to human health.

“These companies knew for decades that PFAS chemicals could cause serious harm to human health yet continued to advertise them as safe for household use around families and children,” Paxton said in a press release.“Texas is taking action to penalize these companies and hold them accountable for deceiving Texans into buying consumer products without vital information.”

Daniel Turner, a spokesperson for DuPont, said in an email that the company has never manufactured PFOA and PFOS two types of PFAS chemicals or firefighting foam.

"While we don’t comment on litigation matters, we believe this complaint is without merit, and we look forward to vigorously defending our record of safety, health and environmental stewardship.

Representatives of 3M could not be immediately reached for comment.

PFAS,or per- and polyfluoroalkyl substances,are a family of manmade chemicals used to make products that resist heat, oil,stains, grease,& water.Some estimates list more than 12,000 types of individual PFAS.They’ve been used in industry and consumer products worldwide since the 1940s and have earned the name “forever chemicals” because they don’t break down and can persist in water and soil indefinitely.

Exposure to specific PFAS has been linked to certain types of cancer, birth defects,damage to the liver and immune system.They also accumulate in animals,plants,and humans, contaminating drinking water and even circulating in human blood.

The lawsuit was filed in Johnson County nine days after a Texas Tribune story featured farmers in that county who have sued a fertilizer company,alleging the fertilizer they sell, which is made from municipal waste,contained PFAS that poisoned their land and killed their livestock.The farmers say they are not able to make a living off their own land because of the contamination.

Dana Ames, the environmental crime investigator for Johnson County who discovered the contamination on the farmers' land,said the lawsuit represents a significant step forward in the ongoing fight against PFAS contamination.

I was over the moon.It's a legal issue and he's [Paxton] our top lawyer for the state so I am very encouraged to see that he has taken this action,Ames said.

Many other farmers in other parts of the country have also shut down their operations due to PFAS contamination after using fertilizer made from biosolids produced from human waste.

Laura Dumais, a staff attorney with Public Employees for Environmental Responsibility, said Paxton's lawsuit underlines how addressing PFAS is not a partisan issue. The environmental group helped the Texas farmers with PFAS testing.

"As the overwhelming scope of the 'forever chemicals' crisis becomes increasingly apparent, Americans across the spectrum of political affiliation are clamoring for an end to the poisoning of their land, water, and food," Dumais said. "I hope that emerging lawsuits, along with increased public awareness, will begin to make a difference."

DuPont and 3M are two of the most prominent companies associated with these chemicals. Both companies have been historically involved in the manufacture, use and distribution of PFAS. In 2022, 3M announced plans to exit PFAS manufacturing by 2025 as part of its response to growing environmental and legal pressures.

According to Paxton's lawsuit, 3M and DuPont marketed their PFAS products for more than 70 years despite knowing the dangers for more than half a century. The suit alleges that the companies concealed critical risks, misrepresented safety claims, and continued promoting the chemicals as safe for consumer use. The state is seeking $1 million or more in damages, including civil penalties, attorneys’ fees and costs.

Texas had already taken legal action against PFAS manufacturers, including a lawsuit against Aqueous Film Forming Foam, a firefighting product that has polluted Texas lands and waterways.

“Attorney General Paxton has been at the forefront of holding companies responsible for exposing people to dangerous 'forever chemicals.' ” said a statement from the AG’s office. “Today’s lawsuit marks a new stage in PFAS litigation.”

Texas has found PFAS contamination in some drinking water systems: Nearly 50 public water systems across the state have reported exceeding the U.S. Environmental Protection Agency’s newly-released PFAS limits for drinking water.

source:The Texas Tribune

Today's KNOWLEDGE Share :Fatigue Failure

Today's KNOWLEDGE Share

Fatigue is a complicated aspect of plastic parts failure.

While most are aware of the need to keep frequency low in a fatigue test to avoid local heating of the sample, many may not be aware of the following extremely interesting tests to be done.

Let us say you test your sample (at some T and a given Stress Ratio, like 0.1) at 1 Hz and also 2 Hz.

Would you expect your part to fail after :

- the same number of cycles ? or

- the same testing time ?

Well, in a nutshell, if you fail at the same total time (twice the number of cycles) that indicates that your failure is Plasticity Controlled. A DUCTILE failure.

If you fail at the same number of cycles (i.e. half the testing time) your failure is Crack Growth controlled. A BRITTLE failure.

Of course things may be somewhat intermediate, but such simple tests will really inform you about the failure mechanism and help consider better materials for the application.

The test is particularly interesting for GF or CF filled polymers because the lack of visible deformation is often wrongly interpreted as BRITTLE fail !

source:Vito leo

Today's KNOWLEDGE Share :Plasma Technology using Tire to Clean Energy

Today's KNOWLEDGE Share

I will share the new design in the field of tire and plastic gasification.

The exiting very high temperature (800 C) level syngas transports the oil vapors from the rubber to the condenser, inside the pyrolysis of the rubber/plastic takes place together with the exiting gas, the gas temperature is further increased by the microwave radiation from the gas. the outside, which converts the exiting oil vapor into non-condensable gases above 1000 C, such as H2, CH4, CO, CxHx, etc.

We have recently started the production of a series for the gasification , the electrical energy requirement of microwave steam plasma torch excitation is one-tenth of that of arc plasma, and NOx is not generated.

In addition, plasma burners are used to oxidize flue gases, which is a key step in various industrial processes. The radiation from magnetrons can actually break down oil vapors into synthesis gas, making it a highly efficient way to produce clean energy.

In addition, the radiation from plasma torches can be directed through ceramics to reach temperatures above 1000°C. This high-temperature capability is vital for many applications, including material processing and waste management.

It's amazing how plasma technology can be utilized for such a wide range of applications!

microwave technology: www.gumienergia.hu

source:Jozsef Nagy

Today's KNOWLEDGE Share : Recycling of Colorants to second life

Today's KNOWLEDGE Share

New recycling techniques aim to give colorants a second life

Over the next five years, Bert Weckhuysen will investigate how colorants from plastic bottles can be recycled more effectively. In August, he received a grant from the initiative Circular Plastics NL, funded by the Dutch National Growth Fund. Weckhuysen is collaborating with Jules Roelofs from Holland Colours, a manufacturer of colour concentrates, and CuRe Technology, a plastic recycling company.

Walk through any supermarket and you will see shelves lined with plastic bottles in every colour of the rainbow: green, red, blue – added to plastics to make packaging more appealing. But what happens to all those colorants once the bottle is empty and sent for recycling? At present, not much. Most colorants are lost in the recycling process as the plastic is often burned or, at best, reused. According to Bert Weckhuysen, Distinguished University Professor of Catalysis, Energy, and Sustainability at Utrecht University, this needs to change.

Thanks to a grant from Circular Plastics NL, Weckhuysen now has five years to explore how colorants in plastics can be recycled. Together with Holland Colours and CuRe Technology, his research group aims to develop technologies to recover both inorganic pigments and organic dyes from polyesters, evaluate their quality, and reuse them in recycled materials.

The value of colorants

Colorants in plastics are often lost during the recycling process – a missed opportunity, says Weckhuysen. “Colorants and other additives give PET bottles their desirable properties and therefore their value,” he explains. “These molecules are often expensive to produce and have a significant environmental footprint. What if we could recover those colorants and reuse them, just like we aim to do with the plastic itself?”

Greener solvents

Recycling colorants requires an overhaul of the current recycling process. “Right now, the focus is primarily on recycling the polymers – the long chains of atoms that form plastics,” says Weckhuysen. To include the colorants in this process, they first need to be extracted from the plastic.

This is where solvents come in, but many commonly used solvents are harmful to the environment. Weckhuysen’s team is taking a different approach: “We are opting for greener solvents made from bio-waste, making the entire process more sustainable.” This approach, which Weckhuysen calls ‘double green’, ensures that both the colorants and the plastic are given a second life in a more environmentally friendly way.

Step by step

The team has already devised a roadmap for extracting colorants from PET bottles. First, the colored PET bottles are dissolved in bio-based solvents, separating the colorants from the polymers. Next, they use light-based spectroscopy to determine which colorants are still usable. This technique allows the team to distinguish between damaged and intact colorant molecules, identifying which ones can go through another cycle. The usable molecules are then filtered out for reuse. “It’s a process of refinement,” Weckhuysen explains. “Every usable colorant we recover is another step closer to a fully circular system.”

Sorting challenges

Not all colorants will be equally easy to recycle, and sorting the colorants will be a key challenge for the project. Some colorants are more complex than others or more costly to process. “Colorants impact recycling in ways that aren’t always visible,” says Jules Roelofs, Global Innovation Manager at Holland Colours. He explains that different colorants require different approaches, which can complicate the recycling process, especially when it comes to detecting and separating colored plastics. “Sorting is crucial,” Roelofs emphasises. “We need to understand the different streams of colorants and determine which ones can be recovered and which might not be worth the effort.”

From research to real-world application

If all goes according to plan, Weckhuysen and Roelofs hope to scale up their project and implement it in practice. “Our ultimate goal is to apply this knowledge and bring the technique to market. CuRe Technology will play a pivotal role in this effort. This mid-sized company specialises in polyester recycling and has developed an innovative process for continuous polyester recycling. While they currently process several kilograms per hour, their ambition is to expand to installations capable of recycling multiple kilotons annually.

“It would be amazing if we could produce products using recovered colorants,” Roelofs says enthusiastically. “Our ultimate goal is 100% reusability. By extracting colorants from plastics, we can not only reuse the colorants but also preserve the quality of the plastic, enabling it to be recycled more frequently.”

source:Utrecht University

Today's KNOWLEDGE Share : phthalonitrile resin

Today's KNOWLEDGE Share

Novel liquid phthalonitrile monomers towards high performance resin:

Phthalonitrile resins are one of the high temperature resistant polymers which can be potentially used for harsh environments in both military and domestic fields. The high melting points of the monomers led to short processing windows and made processing procedure challenging and energy intensive. To solve this problem, liquid phthalonitrile monomers containing flexible siloxane segments were designed and synthesized. The long bond length and large bond angle of Si-O-Si chain segments introduced flexibility into the monomers and effectively reduced the melting point to −35.9 °C. Meanwhile, the high bond energy preserved the thermal stability of the resulting cured resin. The high fluidity (viscosity of ∼ 2 Pa·s at 30 °C) allows the monomers to be processed at room temperature without additional heating. In addition, the monomers can be dissolved in common organic solvents, such as ethyl acetate and ethanol. The resins cured at 250 °C demonstrated good thermal and thermal oxygen stability. The weight loss of 5 % in argon and air at temperatures of 428.6 °C and 434.9 °C, respectively.

Furthermore, blending this liquid monomer blended with powdered monomers improved both the processibility of the high melting monomers and the overall temperature resistance of the cured resin. The resin showed a weight loss of 5 % in argon and air of 534.4 °C and 532.3 °C, respectively.

Conclusion:

Phthalonitrile monomers with melting points below room temperature were successfully synthesized by introducing siloxane segments. The flexible Si-O bond with high bond energy reduced the melting point while preserving thermal stability. The ideal fluidity at room temperature provides an appealing choice for phthalonitrile-based resins that precludes stringent processing requirements such as high temperature, complex equipment, and high energy consumption. 

source:Muyao Gao,, Tianhao Li and their team/Elsevier

Today's KNOWLEDGE Share : EU regrets lack of conclusion on global plastics agreement

Today's KNOWLEDGE Share

EU regrets lack of conclusion on global plastics agreement

After two years of negotiations, UN member states failed to reach an agreement.

The EU regrets that the 5th session of the Intergovernmental Negotiating Committee on the Global Plastics Treaty (INC-5) finished without a deal yesterday in Busan, South Korea.

After two years of negotiations and a week of talks in Busan, UN member states could not find an agreement on what would have been the first-ever global legally binding instrument to end plastic pollution. The session has now been suspended and negotiations will continue in 2025. 

Speaking on the result, Jessika Roswall, Commissioner for the Environment, Water Resilience and a Competitive Circular Economy said:

“I strongly regret that there is no agreement on a new global plastics treaty. If business as usual continues, plastic production will triple by 2060.

“The EU will remain firmly committed to finding a global solution. Our oceans, our environment and citizens around the globe need it.” 

The EU remains strongly in favour of such a global instrument and calls on the countries obstructing the deal to show more ambition when the preparations for a new negotiation process resume.

With plastics leaked into the environment forecasted to triple by 2060, half of all plastic waste still being landfilled and less than a fifth recycled, a decisive response to the global pollution crisis is needed.

Almost two-thirds of plastic waste in 2060 will be in the form of short-lived items such as packaging, low-cost products and textiles, according to the OECD.  

Lack of convergence around treaty objectives:

The negotiators sitting around the table could not unite around a text of a binding instrument with disagreements most notable on measures for the reduction of overall plastic production, the elimination of certain plastic products, chemicals of concern in products, improved design of plastics, extended producer responsibility and enhanced waste management.  

The main points of divergence were a possible target of reducing the production of primary plastic polymers, bans and restrictions of chemicals of concern in plastic products, as well as problematic and avoidable plastic products. It is on this that major oil-producing countries and the “High Ambition Coalition” countries which includes the EU, the UK, Canada, as well as many African, Latin American and Pacific countries could not find convergence.  

Even though no agreement was reached in Busan, the negotiating committee has made significant progress towards a deal by agreeing on a text that should serve as a basis for negotiations at the next meeting. An overwhelming majority of more than 100 countries shared the ambitions of the EU and the number of countries continues to grow. 

source:European Commission

Today's KNOWLEDGE Share : PEKK vs PEEK

Today's KNOWLEDGE Share

PEKK (Polyetherketoneketone) vs PEEK (Polyetheretherketone):

PEKK and PEEK are both in the Polyaryletherketone family of ultra-high performance polymers. 

Unlike PEEK, PEKK is a copolymer with a slower and highly tunable crystallization rate making it the preferred choice for additive manufacturing. Kepstan® PEKK can be printed directly in either the amorphous or semi-crystalline state, or printed amorphous and crystalline in a secondary process, offering the ultimate combination in performance and processing flexibility.

   

CHEMICAL COMPOSITION AND STRUCTURE

PEKK :

Structure: PEKK consists of ether (O) and ketone (C=O) linkages, with two ketone groups in the repeating unit. This structure provides high thermal stability and chemical resistance, making PEKK ideal for demanding environments.

PEAK :

Often confused with PEKK, PEAK is a general term referring to various types of polyetherketones. It includes polymers with similar structures but slight variations in the arrangement of ether and ketone groups, encompassing both PEKK and PEEK among others.

THERMAL PROPERTIES

PEKK:

PEKK boasts a higher glass transition temperature (Tg) and melting point compared to PEEK.

Tg typically ranges between 160°C to 165°C.

Melting point is around 340°C.

PEEK:

Tg is around 143°C.

Melting point is approximately 343°C.

MECHANICAL PROPERTIES

PEKK:

The additional ketone group in PEKK increases rigidity, resulting in higher mechanical strength and stiffness.

It offers better wear resistance and a lower coefficient of friction, which is advantageous for high-stress applications.

PEEK:

PEEK provides an excellent balance of toughness, stiffness, and strength.

It is slightly more flexible than PEKK, which can be beneficial for applications requiring a degree of ductility.

CHEMICAL RESISTANCE

PEKK:

The more rigid structure of PEKK grants it superior chemical resistance.

It excels in resisting a wide range of chemicals, including acids, bases, and organic solvents.

PEEK:

PEEK is highly resistant to many chemicals, though slightly less so compared to PEKK.

Its chemical resistance is still exceptional, making it a reliable choice for harsh environments.

PROCESSING AND APPLICATIONS

PEKK:

PEKK can be processed using similar methods as PEEK, such as injection molding, extrusion, and 3D printing.

It is commonly used in aerospace, automotive, and medical applications where high performance is required under extreme conditions.

PEEK:

PEEK is widely used across various industries, including aerospace, automotive, electrical, and medical devices.

It is easier to process than PEKK due to its slightly lower melting point and greater flexibility.

Additive Manufacturing and Injection Molding

Both PEKK and PEEK have significant implications for additive manufacturing (3D printing) and injection molding.Their high-performance properties allow for the production of complex, precision parts that can withstand extreme conditions.

source::addmangroup/arkema