polymerguru

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 ...

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 f...

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 radi...

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, an...

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, s...

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 o...

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 s...