Today's KNOWLEDGE Share : Researchers Create Deployable Silk Fibers for Adhering and Lifting Objects

Today's KNOWLEDGE Share

The stream of liquid silk quickly turns to a strong fiber that sticks to and lifts objects

These sticky fibers, created at the Tufts University Silklab, come from silk moth cocoons, which are boiled in solution and broken down into their building block proteins called fibroin.The silk fibroin solution can be extruded through narrow bore needles to form a stream that, with the right additives, solidifies into a fiber when exposed to air. 

Nature is the original inspiration for deploying fibers of silk into tethers, webs, and cocoons. Spiders, ants, wasps, bees, butterflies, moths, beetles, and even flies can produce silk at some point in their lifecycle.Nature also inspired the Silklab to pioneer the use of silk fibroin to make powerful glues that can work underwater, printable sensors that can be applied to virtually any surface, edible coatings that can extend the shelf life of produce,a light collecting material that could significantly enhance the efficiency of solar cells, and more sustainable microchip manufacturing methods.

However, while they made significant progress with silkbased materials, the researchers had yet to replicate the mastery of spiders, which can control the stiffness, elasticity, adhesive properties of the threads they spin. 

A breakthrough came about purely by accident.Working on a project making extremely strong adhesives using silk fibroin, and while I was cleaning my glassware with acetone, I noticed a web-like material forming on the bottom of the glass.

The accidental discovery overcame several engineering challenges to replicating spider threads. Silk fibroin solutions can slowly form a semi-solid hydrogel over a period of hours when exposed to organic solvents like ethanol or acetone, but the presence of dopamine, which is used in making the adhesives, allowed the solidification process to occur almost immediately. When the organic solvent wash was mixed in quickly, the silk solution rapidly created fibers with high tensile strength and stickiness.

The next step was to spin the fibers in air.The researchers added dopamine to the silk fibroin solution, which appeared to accelerate the transition from liquid to solid by pulling water away from the silk. When shot through a coaxial needle, a thin stream of the silk solution is surrounded by a layer of acetone which triggers the solidification. The acetone evaporates in mid-air, leaving a fiber attached to any object it contacts. The researchers enhanced the silk fibroin-dopamine solution with chitosan, a derivative of insect exoskeletons that gave the fibers up to 200 times greater tensile strength, and borate buffer, which increased their adhesiveness about 18-fold.

The diameter of the fibers could be varied between that of a human hair to about half a millimeter, depending on the bore of the needle.

The device can shoot fibers that can pick up objects over 80 times their own weight under various conditions.

Natural spider silk is still about 1000 times stronger than the man-made fibers in this study. But with a little added imagination and engineering, the innovation will continue to improve and pave the way for a variety of technological applications. 

“As scientists and engineers, we navigate the boundary between imagination and practice. That’s where all the magic happens,” said Fiorenzo Omenetto, Frank C. Doble Professor of Engineering at Tufts University and director of the Silklab. “We can be inspired by nature. We can be inspired by comics and science fiction. In this case, we wanted to reverse engineer our silk material to behave the way nature originally designed it, and comic book writers imagined it.”

source:Tufts University

Today's KNOWLEDGE Share : Plastic-Degrading Microbes in Mangrove Soil

Today's KNOWLEDGE Share

Researchers Identify Plastic-Degrading Microbes in Mangrove Soil

An international team of researchers has developed a novel method to select bacteria from mangrove soils capable of transforming plastic. This breakthrough offers a potential new approach to tackling plastic waste pollution. By analyzing the effects of polyethylene terephthalate (PET) particles and seawater intrusion on the microbiome of mangrove soil, the team was able to cultivate a collection of PET-degrading microbes.

With plastic pollution reaching alarming levels globally, even in remote ocean environments, ecosystems like mangroves—crucial biodiversity hotspots—are under threat from various stressors, including plastic contamination.

“Mangrove ecosystems are exposed to significant plastic pollution, and their soils harbor diverse microbial communities, including those with potential plastic-degrading capabilities,” explained Diego Javier Jiménez Avella, a research scientist from the Microbial EcoGenomics and Biotechnology Laboratory (MEGBLab) at KAUST, who led the study. “We hypothesized that these soils could be a valuable source of plastic-degrading microbes, although microbial diversity and metabolic activity in mangrove soils remain largely unstudied.”

The research revealed the presence of a novel bacterial genus, Mangrovimarina plasticivorans, which carries genes encoding enzymes known as monohydroxyethyl terephthalate hydrolases—capable of breaking down PET byproducts. This is the first time a bacterial consortium from mangrove soil has been shown to transform a fossil-fuel-based plastic like PET.

"Engineering microbiomes to effectively degrade plastics is a promising yet complex task," Jiménez said. "While we are excited about these findings, scaling the approach and applying it in natural environments pose significant challenges."

This innovative approach to microbial inoculation and enzyme cocktail design could be extended to a variety of ecosystems, potentially uncovering more novel plastic-degrading microbes or enzymes. The research team, which began their collaboration in 2021, includes experts from Colombia, Brazil, the U.S., Germany, Australia, the U.K., and Saudi Arabia. 

“These findings represent a significant step toward addressing plastic pollution, but further research and development—such as optimization and scalability—are needed before they can be practically applied on a large scale,” said Alexandre S. Rosado, the principal investigator at KAUST and leader of the MEGBLab.

The team continues to explore the plastic-degrading potential of microbial communities from Red Sea mangroves, with the goal of advancing these early laboratory results into effective solutions for real-world applications.

source:King Abdullah University of Science and Technology/wkaiglobal.com

 

Today's KNOWLEDGE Share : Carbon Fiber Production Part1/5

Today's KNOWLEDGE Share

Insights into carbon fiber production (Part 1/5)!

Oxidation - the beginning of carbon fiber production

Large piles of PAN precursor mark the beginning of carbon fiber production with PAN precursor, the main precursor valued for its high strength and heat resistance. The oxidation process consists of several stations where the fiber is continuously oxidized and cleaned of anything that is not carbon. After the fifth oxidation oven, the fiber finally emerges from the ovens completely dark and chemically refined.

Safety is our top priority: Our ovens are equipped with advanced fire protection systems to minimize the risk of fire. Even in the event of yarn breakage, our sophisticated systems ensure that each yarn is returned to the process without waste.

source:Teijin Carbon America,Inc

#carbonfiber #carbonfiberproduction #oxidation

Today's KNOWLEDGE Share : BASF additional production capacity for expandable polystyrene (EPS)

Today's KNOWLEDGE Share

BASF Ludwigshafen announces additional production capacity for expandable polystyrene (EPS) granules by 50,000 tonnes/year.

BASF is strengthening its styrene value chain at the Ludwigshafen site by increasing annual production capacity for Neopor by 50,000 tonnes. The increase is aimed at meeting the growing market demand for grey insulation materials. The new production facility is scheduled to be commissioned in early 2027.

 

Neopor is a graphite-containing expandable polystyrene (EPS) granule developed by BASF as a raw material for the production of energy-saving thermal insulation for building envelopes. The graphite content gives the material a grey colour and improves the thermal insulation performance of the sheets by 30% compared to white EPS. Neopor insulation sets new standards for new and refurbished buildings.

 

"BASF's sustainability assessment ranks Neopor as a 'pioneer' in the highest category and is part of BASF's 'solutions for a sustainable future'," said Stephan Kothrade, member of the Board of Executive Directors and Chief Technology Officer of BASF SE. "Our goal is to be the chemical company of choice for our customers and help them achieve a green transition. Neopor is a great example of how we can achieve this goal."

 

BASF expects that the demand for energy-efficient building renovation materials will increase significantly in the coming years. The EU's goal is to make the European construction industry climate neutral by 2050. To achieve this ambitious goal, all EU member states implement the European Building Energy Efficiency Directive, which places high demands on improving building energy efficiency.

 

“Well-insulated building envelopes are essential for reducing greenhouse gas emissions and achieving climate targets. This is also a prerequisite for the rational use of modern heating technology. Our polystyrene insulation materials play an important role in this regard,” said Klaus Ries, Head of Business Management Europe at BASF Styrenics.

 

“Over their decades-long service life, they significantly reduce CO2 emissions and energy consumption for heating/cooling buildings. This is not only good for the climate, but also saves energy costs. Neopor with graphite has excellent insulation values and is easy to process, cost-effective and recyclable. Neopor is one of the most environmentally friendly insulation materials.

souce:BASF/echemi.com

Today's KNOWLEDGE Share : Issues with color masterbatches in Injection Molding

Today's KNOWLEDGE Share

Understanding Common Issues with Color Masterbatches in Injection Molding

The use of color masterbatches is prevalent in injection molding. However, over the years, I have frequently encountered several issues that typically result in surface defects on the molded parts.

These issues can be categorized into three main scenarios:

1. Incompatible Carrier Materials

Sometimes, masterbatches (e.g., with 50% pigment and 50% carrier) use a high-flow carrier like LLDPE, even when the host polymer to be colored is not LLDPE-based.

Issue: The incompatible high-flow carrier is pushed to the surface by hydrodynamic forces. For instance, small amounts of LLDPE in a nylon part can readily create blisters or delamination.

2. Neglecting to Dry the Masterbatch

In nylon or polyester parts, even when the masterbatch uses the correct carrier (same as the host matrix to be colored), users often neglect to dry the masterbatch, drying only the bulk resin to be molded.

Issue: Users may assume that the small amount of masterbatch added doesn’t need drying. However, a very wet, small amount of carrier can cause surface blooming, silver streaks, and potentially significant hydrolytic degradation issues in sensitive materials like PET or PBT.

3. Improper Dispersion of Masterbatch

Even when the masterbatch uses the correct carrier and is properly dried before feeding into the hopper, part issues can still arise.

Issue: The problem often stems from less than perfect dispersion of the masterbatch in the injection molding machine screw. These screws are not always ideally designed and may lack the ability to fully disperse the pigment, leading to color issues due to inhomogeneous color concentrate.

Understanding and addressing these common issues can significantly improve the quality of injection molded parts. Ensuring compatibility of carriers, proper drying of materials, and optimal dispersion techniques are crucial steps in achieving defect-free products.

credit:Vito leo

#plastics #injectionmolding #plasticmasterbatch

Today's KNOWLEDGE Share :Neste and Braskem announce agreement on supply of renewable and recycled feedstocks

 Today's KNOWLEDGE Share

Neste and Braskem, the largest producer of thermoplastic resins in the Americas, have reached an agreement for the supply of renewable and recycled feedstocks for polymers and chemicals production. Braskem products based on these feedstocks are expected to be available on the market starting from the fourth quarter of 2024. These products will be sold mainly in South America and included in Braskem’s Wenew product portfolio. 

“This is a very important moment for the industry. We're introducing a new solution that will adhere to the industry’s high quality standards while ensuring sustainability right from the start of the value chain. This partnership with Neste is a significant milestone in our journey towards a circular economy,” stated Fabiana Quiroga, Director of Circular Economy at Braskem in South America. 

Braskem will sell polymer resins and chemicals made from Neste’s more sustainable feedstock Neste RE™: the recycled feedstock, produced leveraging plastic waste via chemical recycling, and the renewable feedstock produced by processing renewable raw materials such as used cooking oil (UCO). 

“We are excited to welcome Braskem as our partner in advancing the transformation of the plastics and chemicals industry towards more sustainable solutions,” emphasizes Jeroen Verhoeven, Commercial Director for Polymers and Chemicals at Neste. “We are looking forward to seeing our Neste RE solution in action in South America, reducing the dependence on virgin fossil feedstock in the production of polymers and chemicals.”

An ISCC PLUS (International Sustainability and Carbon Certification) certified mass balance approach will be applied to integrate the new feedstocks into Braskem's existing processes. This will give customers further reassurance regarding the uninterrupted chain of custody and the sustainable sourcing of the materials.

An innovative solution with clear climate benefits

By combining chemically recycled and renewable solutions, Braskem builds upon two of the most promising solutions to reduce the use of virgin feedstock and to promote sustainability in chemicals and plastics value chains. 

Chemical recycling enables the recycling of those types of plastic waste that are otherwise difficult to recycle, for example multi-material or colored plastics. In this sense, Neste’s chemically recycled feedstock can contribute to increasing recycling and therefore help reduce the amount of plastic waste entering the environment. 

Neste's renewable feedstock, on the other hand, can help reduce greenhouse gas (GHG) emissions when replacing fossil feedstock in the manufacturing of plastics and chemicals. It is produced using renewable raw materials such as waste and residue oils and fats like used cooking oil or residues from vegetable oil processing. 

source:Neste Corporation

Today's KNOWLEDGE Share : PA6-based WRAS-certified Solutions for Drinking Water Applications

Today's KNOWLEDGE Share

DOMO Introduces PA6-based WRAS-certified Solutions for Drinking Water Applications

DOMO Chemicals announces the successful achievement of the first PA6-based Water Regulation Approved Scheme (WRAS)-certified solutions, demonstrating that the material is suitable for drinking water contact applications. 

Eliminates Risk of Galvanic Corrosion and Scale Formation:

With increasing urbanization, one of today’s key challenges is to provide sustainable access to quality water. An optimal way to do this is to provide advanced polyamide technology for metal replacement and high-end polymers for the water management industry. This helps to ensure greater sustainability, lower system and maintenance costs, and easier and safer handling of water.  

"Our new range of TECHNYL® SAFE C can effectively replace brass and other metals in water distribution, filtration and irrigation, sanitary and small appliance components requiring WRAS approval up to 85°C," said Paolo Rossi, Industrial Consumer Goods Application Development manager, DOMO Chemicals. "The portfolio has been developed to provide a specific property profile compared to current best-in-class materials and to meet the regulatory requirements for contact with drinking water set out in BS6920-1:2000 and/or 2014, which define compliance with WRAS." 

DOMO's metal replacement materials eliminate the risk of galvanic corrosion and scale formation, and provide significant system savings compared to the high cost of processing and machining new brass alloys and the high environmental impact of foundry end products. 

Water management applications have very specific requirements, such as good mechanical properties retention after long-term water contact with chlorine (disinfectants) even at warm temperatures, as well as long-term dimensional stability and oxidative degradation resistance. The most common applications in this field are water filtering, water softeners and metering systems, submersible pumps, shut-off valves, fittings, faucets, cartridges, boiler components like hydro-block manifolds, along with balancing and other small home appliance parts. 

Water Regulation Approved Scheme

WRAS approval is a simple way of demonstrating that a material is of a suitable quality and standard and has been tested to demonstrate compliance with BS6920. 

Any water fitting which, when installed, will carry or receive water from the public water supply in the UK must comply with the Water Supply Regulations or Scottish Byelaws.These require that a water fitting must not cause waste, misuse, excessive consumption or contamination of the water supply and must be "of an appropriate quality and standard.” Non-metallic materials and components are only tested for their effect on water quality.  

The new TECHNYL® SAFE C solutions complement the existing WRAS-certified TECHNYL® SAFE portfolio of water and food contact, based on PA66 and PA6.10. 

source: DOMO Chemicals/omnexus.specialchem.com