Today's KNOWLEDGE Share : CNSL for Brake Pads

Today's KNOWLEDGE Share

Development of Refined Natural Resin based Cashew Nut Shell Oil Liquid (CNSL) for Brake Pads Composite

Development the composite-based brake pads aim to reduce the damage of train wheels and sparks during braking continually. Cashew Nut Shell Liquid (CNSL) is an oil composed from a complex phenolic compounds with long carbon chain branched and unsaturated. CNSL extraction that's done using hot water, which is then dried to remove water from the extract of physical separation by centrifugation.The main structure CNSL is 90% anarcadic acid and 10% cardol, but in detail components in the CNSL separated will depend on the treatment path will be executed.

The increase in the levels of cardanol done through extraction using semi-polar and non-polar solvent. Raw CNSL has a high relative density because it has anarcadic acid as the major fraction, there is intermolecular attraction between the electronegative oxygen atom and the partially positive hydrogen atom of the phenol core as a result the molecules are closely packed together. The structure of anacardic acid, cardol, cardanol and 2-methyl-cardol were founded in crude CNSL. CNSL compound was added as a resilience in the binder system and reduces brake noise. 

FTIR analysis of technical CNSL and decarboxylated CNSL result were shown. Infrared spectra absorption were in the regions of 3424 cm-1, 2700-2900 cm-1, 1615 cm-1, 1200-1600 cm-1, and 500-700 cm-1 representing as -OH hydroxyl, C-H stretching, C-O, C=C aromatic stretching, and aromatic ring respectively. The presence of –OH hydroxyl has a role as a reactive group which will react with other components of composite material, so that CNSL can be used as an alternative of phenolic resin. But, raw CNSL still content impurities so that needed decarboxilation procedure to remove the impurities.

Simulant Thermal Analysis (STA) for the determination of thermal resistance of materials. Based on thermal analysis using STA indicated that the CNSL has high stability in temperature under 400 ºC, proved by the small decrease of its mass in the temperature range of 0 - 350 ºC. Nevertheless, when the temperature up to 400 ºC, the more mass loss because of the decomposition of the CNSL coumpound.

Cashew nut shell liquid (CNSL) have been used as a substituent of phenolic resin. The CNSL compound of cardanol, acid cardanol and cardol can act as a binder in the brake pads composite preparation due to the functional group in their compound. Infrared test showed the presence of hydroxyl groups belong Cardanol. The CNSL has high stability in temperature under 400 ºC, proved by the small decrease of its mass in the temperature range of 0 - 350 ºC. The addition of CNSL resin also improve mechanical properties of brake pads composites proven by higher tensile strenght, elongation and excellent pressure strength of formula 2, 900 N, 2,59 MPa and 20.000 N respectively.

source: S Wahyuningsih et al 2017 IOP Conf. 

Hexagon Composites’ net zero targets validated by the Science Based Target initiative

Hexagon Composites, world leader in composite cylinder technology and systems for storage and transportation of clean gaseous energy, has committed to being net zero by 2050. In July 2024, Hexagon’s net zero targets were validated by the Science Based Target initiative (SBTi).

The SBTi defines and promotes best practice in science-based target setting, and independently assesses and approves companies’ targets. Being a provider of solutions that help fleets and OEM’s transition to low-carbon and carbon negative solutions, Hexagon recognizes the importance of reducing its own carbon footprint and is proud to join the over 5,800 businesses around the world that are working with the Science Based Targets initiative (SBTi).

“We are pleased to have received the approval of our science-based net zero targets by SBTi,” says Jon Erik Engeset, CEO Hexagon Composites. “While we enable other industries to accelerate the pace of their emission reductions, we are committed to doing our part to reduce the environmental impact of our operations and support the 1.5-degree target.”

In line with the 1.5-degree trajectory, Hexagon will reduce its direct emissions by 2033, and work with partners and suppliers to be net zero across its value chain by 2050.

Near-term targets:

By 2033, Hexagon commits to reducing 54.6% of absolute scope 1 and 2 emissions and 61% of Scope 3 emissions per cubic meter of container volume sold.

Long-term targets:

By 2050, Hexagon commits to reducing 90% of absolute scope 1 and 2 greenhouse gas emissions, and 97% of Scope 3 emissions per cubic meter of container volume sold.

Hexagon will report its progress on a regular basis.

source:Hexagon Group/www.jeccomposites.com

Today's KNOWLEDGE Share : Loss of molecular weight

 Today's KNOWLEDGE Share

 It is fairly common knowledge that a loss of molecular weight, as possibly induced by degradation, will produce parts with lower mechanical performances.

Some people however believe that a simple test like a stiffness/modulus check can confirm the absence of degradation. Wrong !

If you take, say, PP, a loss of molecular weight will actually speed-up crystallization kinetics typically resulting in slightly stiffer parts.

However, should you focus on strength, impact, creep performance, fatigue, crack growth, fracture toughness or similar long term properties, you would see a clear loss of performance.

Also, remember that chain scission in Injection Molding typically does not produce any smoke, discoloration or other easily spotted defects. This is why one should cautiously check molecular weight, one way or another, when chain scission is suspected.

Failing to do so creates a huge risk of part failure in the field with serious financial consequences and liabilities.

source:Vito leo

Today's KNOWLEDGE Share :CNSL resins as modifiers

 Today's KNOWLEDGE Share

CNSL RESINS FOR RUBBER APPLICATIONS

Cardolite offers a wide variety of Cashew Nutshell Liquid (CNSL) derived resins for rubber applications. CNSL-based resins can substitute petroleum based phenolic resins as rubber modifiers to improve carbon footprint and lower toxicity of the final compound. CNSL resins can be used as tackifying resins and as plasticizers for polar and non polar rubber while providing additional benefits that could include antioxidant properties and adhesion improvement.

PLASTICIZER AND ANTIOXIDANT FOR ISOPRENE RUBBER

Cardolite CNSL-based phenolic resins can be formulated into synthetic natural rubber to act as plasticizers or process aids that also provide antioxidant properties. These higher molecular weight CNSL polymers are rubber modifiers that help reduce compound Mooney viscosity to similar levels to paraffinic process oils. Moreover, the incorporation of CNSL resins results in enhanced resistance to aging by heat as indicated by lower change in mechanical properties.

Adding Cashew Nutshell Liquid derived resins to rubber results in…

Lower compound viscosity and improved fluidity before vulcanization

Better antioxidant properties

Higher rubber hardness after vulcanization

Lower rubber modulus at high strain that can be adjusted by increased cure with little effect on elongation

source:www.cardolite.com

Today's KNOWLEDGE Share : Renewable resources based phenolic resin

Renewable resources based phenolic resin

The conventional phenolic resin was prepared from formaldehyde and phenol. Formaldehyde used as a raw material in phenolic resins having high toxic nature. Which damages human eyes, and skin, and causes harm by inhalation.In comparison with the others referenced above, furfural is a sort of sustainable heterocyclic aldehyde with a brilliant industrialization prospect. It is primarily yielded from biomass wastes, for example, corncobs and sugarcane bagasse as of now, which is likely use to replace formaldehyde in the synthesis of phenolic resins. In a furfural structure, a furan ring with an aldehyde functional group is attached to in the second position. The replacement of formaldehyde by furfural promotes the thermal stability of the phenolic resin.

Among the agricultural byproduct, Cashew nutshell liquid (CNSL) is the byproduct of the cashew industry and one of the renewable resources is special because it contains cardanol, anacardic acid, which is a phenolic lipid, and cardol, and other chemical compounds are also found in cashew nuts.Riya Srivastava et. al. was a renewable-based resin synthesized by using materials such as cardanol and furfural. They came to the conclusion that the produced cardanol resin can be used as a substitute for phenol resin based on petrochemical derivatives.The tensile and flexural strength of the resin reduced as the amount of cardanol increased when phenol was substituted for it in different molar ratios with formaldehyde. After that, both novolac and resol resins were synthesized with partial substitution of phenol with cardanol. The cardanol-formaldehyde resin was replaced with furfural to enhance its properties. After that substitution of furfural, an increase in mechanical, chemical, and curing properties of cardanol-furfural resin was observed.

Functionalization by Epoxidation

Epoxy phenolic resin is formed by the potential reaction of the epoxide functional group with the hydroxyl group in phenolic resin. Therefore, increasing the functionality of the resin increases its ability to cross-link, creating a more ground polymer with stronger resistance properties. Phenolic resins by themselves produce a high degree of crosslinking through thermosetting, which has high resistance properties to chemicals and water. In these phenolic resins, the polymer repeating unit generated from polymerization may still contain unreacted hydroxyl group (-OH) (C6H5OH). Epoxy phenolic resins change this condition by adding an organic group, such as epichlorohydrin (CL-CH2-(C2H3O)), that has an epoxy-functional group. K. Shukla S. K. et. al. Modified cardanol-based phenolic resins were used with different proportions of epichlorohydrin and functionalized resins were prepared. They studied that, an eco-friendly high-performance thermosetting bio-based epoxy resin is an environmentally friendly alternative compared to commercial epoxy resin.

source:www.orientjchem.org/ Institute of Science and Technology for Advanced Studies and Research (ISTAR)

Today's KNOWLEDGE Share :New reaction to create Monomers using Nickel as catalyst

Today's KNOWLEDGE Share

Chemists develop new sustainable reaction for creating unique molecular building blocks

Scripps Research chemists and additional collaborators have developed a new reaction to create unique monomers in a controlled way. This reaction, which uses nickel as a catalyst, ultimately enables scientists to create polymers with unique and modifiable properties for drug delivery, energy storage, microelectronics and more. The study was published in Nature Synthesis on August 8,2024.

"This study shows how earth-abundant metal catalysts can unlock the path toward previously unknown materials with unparalleled structural and functional diversity," says senior author Keary Engle, PhD, a professor in the Department of Chemistry and dean of Graduate and Postdoctoral Studies at Scripps Research.

The Engle lab at Scripps Research focuses on developing new chemical reactions to build a wide and diverse array of small molecules, typically with applications in drug discovery. In this study, the Scripps Research team collaborated with polymer researchers at the Georgia Institute of Technology and the University of Pittsburgh to test whether their methods could be scaled up to create unique polymers.

"The properties of polymers are very much dependent on what type of chemistry is on the backbone, so if you can modify the chemistry of the building blocks, then you can easily apply it to the macromolecular structure that you're building," says Anne Ravn, PhD, a postdoctoral researcher in the Engle lab at Scripps Research and co-first author on the paper. "With this project we wanted to test whether our strategy for developing small molecules could be applied to a bigger picture to provide new building blocks for polymer synthesis."

The paper's other first authors are Van Tran, PhD, who worked on the project as a graduate student in the Engle lab; Camille Rubel, a current graduate student in the Engle lab; Mizhi Xu, PhD, a former graduate student in the Gutekunst lab at the Georgia Institute of Technology; and Yue Fu, PhD, a former graduate student in the Liu lab at the University of Pittsburgh.

To create the new monomers, the Scripps Research team developed a chemical reaction that alters the structure of a starting molecule by using nickel as a catalyst. The nickel-catalyzed reaction added two new "functional groups" to the molecule -- small side chains that confer different chemical and physical properties on the ensuing polymer, for example, how flexible, elastic or soluble it is.

Then, the team's collaborators at Georgia Institute of Technology used another chemical reaction to link the monomers together via polymerization, resulting in polymers with a unique structure.

"Most commercial polymers have two carbons in between each functional group that are not decorated with any side chains, but in this case, the functional groups are much closer in space, which creates a material with different properties.

In the future, the team plans to explore the impact of substituting different functional groups onto the monomers.

"Our strategy allows us to 'decorate' the molecule with much more flexibility than other methods, which gives us more freedom to explore different types of functionalities in the building blocks," says Ravn. "We're now working to expand the method to explore how introducing other types of functional groups changes the properties of the material."

Because nickel is more abundant than many other metal catalysts used in this type of chemical reaction, the researchers say that their method holds promise as an environmentally sustainable method for polymer production. They're also exploring ways to make the products even more sustainable.

"From an environmental perspective, we want to find a method to degrade these long polymers so that we can get back to the original building blocks, which would allow us to reuse them," says Ravn. "This is a tool that we hope to fine-tune in the future to ultimately create new technologies that are useful for society."

"Ni-catalysed dicarbofunctionalization for the synthesis of sequence-encoded cyclooctene monomers" was co-authored by Ethan Wagner, Steven R. Wisniewski, Peng Liu, and Will Gutekunst of Scripps Research.

Support for the research was provided by the Department of Energy (DESC0023205), the National Science Foundation (CHE-2102550), the Independent Research Fund Denmark (grant ID: 10.46540/3102-00009B), and the Schimmel Family Endowed Scholarship Fund.

source:sciencedaily.com

Today's KNOWLEDGE Share :The difference between HDT and Vicat

Today's KNOWLEDGE Share

Heat deflection temperature (HDT):

HDT is a measure of the stiffness of the material as the temperature increases.

HDT test measures the temperature at which the specimen loses its “load-bearing” capability.

A material can have only “one” HDT.

HDT for material is affected by the addition of reinforcement, fillers, plasticizers, or any other type of additive.

Vicat softening temperature (VST):

The vicat test is used to identify a temperature at which a needle of specified dimensions penetrates a plastic specimen at a specified distance under a given load.

It reveals the temperature at which the specimen loses its “stability-form” and softens.

The vicat point is closer to the actual melting or softening point of the polymer. The Vicat number will typically be higher.

The difference between HDT and Vicat testing:

The main difference between heat deflection temperature testing and Vicat softening point testing is associated with the elements the material being tested is subjected to.  

HDT testing :

HDT testing subjects a standard sized test specimen to stress, while also raising the temperature at a uniform rate. The temperature at which deflection occurs is recorded, which allows you to determine the heat the sample is able to withstand. The result is also dependent on factors such as the load, the speed the temperature is raised and the flexure chosen. This data can be used to compare samples and create an accurate picture of the ways paints and polymer coatings may behave under both heat and stress.  

Vicat softening point testing :

The Vicat softening point method was introduced as a way of determining the softening point of a material or coating. It’s essential because thermoplastic doesn’t have a melting point where solids become liquids, instead they are subject to softening. In Vicat testing, a circular indenter of 1 mm² in section penetrates exactly 1 mm into the specimen under a standardized load of 10 N or 50 N. The indentation is used to calculate how much the specimen has softened.  

 

Meeting industry standards for HDT and Vicat:

HDT testing should be carried out according to testing standards ISO 75 (parts 1, 2 and 3) and ASTM D648 while Vicat testing is ISO 306 and ASTM D1525.  

source:industrialphysics.com/omnexus.specialchem.com

Photo:Amde-Tech