Today's KNOWLEDGE Share : Wetting Agents & Dispersants

Today's KNOWLEDGE Share

What are the differences between wetting agents and dispersants?

Several types of additives can be used in the dispersion process in which solid particles, like pigments and fillers, are distributed and stabilised in a liquid.

Often two categories of additives, wetting agent (EU) and dispersants (EU), are mentioned in one breath. However, the two materials differ strongly with respect to the role they play in the system and with respect to chemical composition and morphology of the molecules they are composed of.

Functionality

It is important to have a clear view on what each raw material that is used in a paint or ink should do. The job a raw material, like an additive, must do in a system is called functionality.

Wetting agents

Wetting is the first step in the dispersion process. The air that surrounds the solid particles in an agglomerate must be substituted by liquid. Wetting will take place when the surface tension of the liquid is low compared to the surface energy of the solid particles. Wetting will not occur when the surface tension of the liquid is too high. In that case, the surface tension of the liquid can be lowered by adding a wetting agent. A wetting agent does its job because the molecules adsorb and orient on the liquid-air interface.

Dispersants

Solid particles attract each other. For this reason, energy is needed to separate the particles from each other in the second step of the dispersion process. Also, solid particles must be stabilised after they have been separated from each other. The particles will move to each other and glue together again when particle-particle repulsion is insufficient. The spontaneous process of gluing together of solid particles in a liquid is called flocculation. The functionality of a dispersant is to prevent flocculation. Dispersants do their job because the molecules adsorb on the solid-liquid interface and assure repulsion between the particles.

Repulsion can result from two mechanisms that may either be used separately or in combination:

Electrostatic stabilisation: all particles carry a charge of the same sign.

Steric stabilisation: all particles are covered with tails dissolving in the liquid that surrounds the particles.

source:essar.com

Today's KNOWLEDGE Share : Polyimide Vs PEEK

Today's KNOWLEDGE Share

PEEK Vs Polyimide - Comparing Two of the Toughest Polymers

In the realm of high-performance polymers, PEEK (Polyether Ether Ketone) and Polyimide stand out as two exceptional materials. Both are undoubtably among the toughest polymers, exhibiting tensile and flexural strengths far higher than even their nearest competitors.

Comparing chemical structure:

PEEK is a semi-crystalline thermoplastic known for its excellent mechanical properties, chemical resistance, and high-temperature stability. Its molecular structure imparts exceptional resistance to chemicals, abrasion, and wear. 

On the other hand, Polyimide (often known by its brand names of Vespel is a high-performance polymer with a unique imide linkage in its molecular structure. This arrangement contributes to outstanding thermal stability, excellent dielectric properties, and exceptional resistance to radiation and chemicals. 

Mechanical Properties:

When it comes to mechanical properties, PEEK and polyimide both display distinct characteristics. PEEK offers a combination of high strength, stiffness, and toughness. Its tensile strength and modulus are comparable to some metals, making it a preferred choice in structural applications where mechanical integrity is crucial. PEEK's inherent toughness allows it to withstand repeated loading and impact without sacrificing performance. PEEK can also be enhanced with the addition of Glass, Carbon, and Graphite (Carbon-Graphite reinforced PEEK, also called HPV PEEK, is among the toughest polymer compounds known), which adds to PEEK’s versatility.

Polyimide, while not as stiff as PEEK, excels in maintaining its mechanical properties at elevated temperatures. Its ability to withstand prolonged exposure to high temperatures without significant degradation makes polyimide suitable for aerospace, electronics, and automotive applications.

When it comes to wear resistance, polyimide take the edge, as it exhibits a slightly lower coefficient of friction. While PEEK can be improved with the addition of PTFE, the base wear rate of polyimide is both low and constant over a range of loads.

Thermal Stability:

Thermal stability is a key consideration in many high-performance applications, and both PEEK and polyimide offer exceptional heat resistance. PEEK is known for its thermal stability up to 260°C, making it suitable for applications in aerospace, automotive, and oil and gas industries. However, polyimide surpasses PEEK in terms of thermal stability, with some formulations capable of withstanding temperatures exceeding 300°C. This makes Polyimide the material of choice in extreme temperature environments such as electronics and aerospace applications.

Chemical Resistance:

Chemical resistance is another critical factor in material selection, especially in harsh operating conditions. PEEK exhibits excellent resistance to a wide range of chemicals, including acids, bases, and hydrocarbons.

source:Poly Fluoro Ltd

BRB Introduces Hydrolytically Stable Wetting Additive for Adhesives

BRB introduces BRB Siloen® WA 264, a hydrolytically stable substrate wetting additive based on polyether siloxane technology. It is designed for water-based coatings, overprint varnishes, printings inks as well as adhesives.

Low in SVHC Content:

BRB Siloen® WA 264 provides a considerable reduction of surface tension thus improving the substrate wetting. It shows a good hydrolytically stability and can be used in a pH range in between 4 to 10 without noticeable degradation of the surface tension.

BRB Siloen® WA 264 is particularly suitable for system not containing co-solvents. It has limited or no foam stabilization and it doesn’t impact the intercoat adhesion (recoatability). Also it doesn’t increase surface slip.

BRB Siloen® WA 264 is low in SVHC content, being Cyclotetrasiloxane (D4), Cyclopentasiloxane (D5) and Cyclohexasiloxane (D6) <0.1% respectively.

Source: BRB/adhesives.specialchem.com

Today's KNOWLEDGE Share :CO2 derived sustainable polyester fiber

Today's KNOWLEDGE Share

World’s first supply chain established for more sustainable polyester fiber based on CO2-derived material as well as renewable and bio-based materials

A consortium of seven companies across five countries has jointly established a supply chain for more sustainable polyester fiber. Instead of fossil materials, renewable and bio-based materials as well as carbon capture and utilization (CCU*) will be used in the manufacturing of polyester fibers for The North Face brand in Japan. The consortium parties are Goldwin, in the role of project owner, Mitsubishi Corporation, Chiyoda Corporation (all three from Japan), SK geo centric (South Korea), Indorama Ventures (Thailand), India Glycols (India) and Neste. 

Neste will provide renewable Neste RE™ as one of the required ingredients for polyester production. The polyester fiber produced in the project is planned to be used by Goldwin for a part of The North Face products, including sports uniforms, in July 2024. After that, the launch of further Goldwin products and brands will be considered. 

The seven companies apply a mass balancing approach to ensure credible traceability of material streams throughout the supply chain and will jointly continue to proactively promote the defossilization of materials to contribute to a more sustainable society.

Regarding the production of para-xylene derived from CO2 as a raw material, the University of Toyama, HighChem Company Limited, Nippon Steel Engineering Co. Ltd., Nippon Steel Corporation, Chiyoda Corporation and Mitsubishi Corporation were granted a NEDO project (New Energy and Industrial Technology Development Organization) status in 2020: "Technology Development for Carbon Recycling and Next Generation Thermal Power Generation/Technology Development for CO2 Emission Reduction and Effective Utilization". They are conducting joint research and development. This project is to supply CO2-derived para-xylene in the course of a trial. It has been produced during the operation process of a pilot plant installed in Chiyoda Corporation's Koyasu Research Park since March 2022.

source:Neste Corporation

Arkema Grants an Exclusive Technology License to SEQENS to manufacture PEKK for sale in Long Term Medical Implantable Applications

SEQENS, an integrated global player in solutions and ingredients for the pharmaceutical and specialty market, is excited to announce a new step in its collaboration with Arkema, a world leader in specialty materials, with the signature of an exclusive technology license for the manufacturing of PEKK for sale in long term implantable applications.

The two companies have partnered for 15 years, combining Arkema’s expertise and intellectual property in PEKK technology together with SEQENS’ recognized know-how in the production of polymers for the pharmaceutical and life sciences markets.

PEKK is a high-performance polymer family used in aerospace and other demanding markets, commercialized by Arkema under the Kepstan® trademark. SEQENS’ IMPEKK materials have been specifically developed for long term medical implantable applications. IMPEKK materials will be provided to the market by SEQENS through a global network of partners, including well-known manufacturers, 3D printing machine companies, and distributors.

source:SEQENS

Today's KNOWLEDGE Share:DOW's Bio-based EPDM

Today's KNOWLEDGE Share

Dow announces bio-based NORDEL™ REN EPDM at DKT 2024

 Dow is proud to announce at the German Rubber Conference (DKT) 2024 the launch of NORDEL™ REN Ethylene Propylene Diene Terpolymers (EPDM), a bio-based version of Dow’s EPDM rubber material that goes into automotive, infrastructure and consumer applications.

A key component of automotive weatherseals and hoses, Dow aims to support not just the automotive industry in achieving its sustainability goals with the launch of NORDEL™ REN EPDM, but as EPDM also goes into building profiles, roofing membranes, wire and cable, among others, NORDEL™ REN EPDM can help the decarbonization of building and construction and more.

The plant-based EPDM will be made through an ISCC PLUS certified mass balance system which traces the flow of bio-based raw material through a complex value chain and attributes it through verifiable bookkeeping.

Dow’s Path to Zero

The arrival of NORDEL™ REN EPDM is part of Dow’s continuous endeavors towards carbon neutrality. The technology behind NORDEL™ EPDM production, Dow’s Advanced Molecular Catalyst, already results in a highly efficient process that uses 24% less energy than the conventional Ziegler-Natta process, and thus 39% lower carbon footprint for the standard NORDEL™ EPDM grades, which has been validated by a third-party life cycle analysis (LCA).

Discover Dow’s portfolio of rubber technologies for decarbonization on show at DKT 2024

NORDEL™ REN is featured at the DKT 2024 along with a range of EPDM and Silicone rubber technologies on show that help lower the carbon footprint of diverse industries:

1. SILASTIC™ Solutions for Electric Vehicles (EV) including High Consistency Rubbers (HCR) and Liquid Silicone Rubbers (LSR) for fire protection and connectivity, advancing electrification of the automotive industry to reduce tailpipe emissions

2. SILASTIC™ Silicone for Self-Sealing Tires, designed to form a self-sealing layer on the inner surface of a tire, allowing long-distance driving without loss of air pressure and supporting easy disassembly of vehicle part for separate recycling of silicone

3. NORDEL™ EPDM innovation for Microdense Weatherseals, aiding in the reduction of overall density of weatherseals and of tailpipe emissions through lightweighting, by bringing enough strength to maintain critical performance of the rubber material

4. Dow’s patented innovation for the creation of LUXSENSE™ Silicone Synthetic Leather, the world’s first silicone-based luxury synthetic material bringing sustainability with lower carbon emissions cradle to gate, solvent-free fabrication process, and animal-free, while offering exceptional haptic feedback and remarkable abrasion resistance

Visit hall 8, stand 103a from 1 – 4 July in Nuremberg, Germany, to learn more about Dow’s innovative rubber options to advance a more sustainable future.

source:Dow

KBR Launches KCOTKlean℠ to Decarbonize Petrochemicals:

Integrating Catalytic Partial Oxidation (CPOx) technology from Korea Institute of Machinery and Materials (KIMM).

KBR is pleased to launch KCOTKleanSM, a suite of low and zero-carbon technologies aimed at decarbonizing the catalytic olefins process. This technology integrates KBR’s Catalytic Olefins technology, K-COT®, with Korea Institute of Machinery and Materials’ (KIMM) CPOx technology. 

KCOTKleanSM achieves significant carbon reduction by leveraging circular feeds, cleaner fuels, electrification or carbon capture. This innovation builds upon KBR’s proprietary catalytic olefins process, K-COT®, known for efficiently converting low-value olefinic, paraffinic or mixed streams into high-value propylene and ethylene. KIMM’s CPOx technology to convert methane-rich fuel into hydrogen-rich fuel optimizes combustion in the catalytic regeneration environment and diversifies fuel options for the K-COT® catalyst regenerator.

“It is our ultimate goal to turn sustainable concepts into reality, supporting our customers as they transition into a more sustainable world,” said Hari Ravindran, senior VP and global head of KBR Technology Solutions. “KCOTKlean represents a step-change in cracking technologies. By integrating KIMM’s innovative technology with our own, we not only enhance the efficiency and performance of our processes, but also contribute to a more sustainable future.”

KBR has licensed over 100 grassroots ethylene plants utilizing its cost-effective and energy efficient cracking technologies and flexible plant designs to produce ethylene, propylene, and other byproducts from a variety of feedstocks.

source:KBR