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based on the various kinds of intermoblite lab, we have learned a lot of things. So we can also examine how these interactions appear in the polymer. First, the atoms that make up the polymer backbones are connected to cobaltent bonds like this one.

Even in cases where the cooselinking occurs, such as through the cipher or other cooselinking agents, the bonds formed are still covalent bonds. In addition to these, we can also observe the other type of interaction. For example, dipole-dipole interaction can occur between the non-polar molecules. and the hydrogen bond

like the significant contribution in the many polymer system and of course the bander virus force are always present for the ionic bonds like this one. CO and the metal cation they have a ionic bondings. Through the various kinds of the examples we can see how all these kinds of flows contribute to the

the overall structure and the properties of the polymers. So one of the examples the hydrogen bondings and the polymers, we already talked about the importance of the hydrogen bondings in the polymer. So the one of the examples is the cellulose. Cellulose is the natural the polymer made of the whippin glucose unit like this one.

unit linked together. Each glucose unit contains multiple the hydroxyl functional group.

hydroxyl can form a strong hydrogen bond with the neighboring the cellulose chains. In the diagram, you can see how the hydrogen atom of the 1OH group is attracted to the oxygen the atoms of another the OH groups on the nearby chains and also the structured oxygen. This hydrogen bond acts as a bridge.

between the chain. Because of these extensive hydrogen bonding networks, cellulose has the high tensile strength, high mechanical properties and the raw solubility in the water because they can form the hydrogen bonding and the forms from the some fiber such as a cotton or and the wood. So this is why hydrogen bonding is one of the most important interactions that determines the mechanical structure property of cellulose.

and also increase the step, the pibrile, interfacial interface, like a huge scale of things. So still they can from the different level, different scale of the hydrogen bondings. So as you can see in these tables, the covalent bonding have greatest bonding strength, like it's dissociation energy, like if you want to

some cut this kind of bonding so we need the dissociation the energy cobalt bonding is 200 levels but in case of the hydrogen bonding just three to seven dipole-life bond interaction 1.53 banderas balls 0.52 but then ionic bond is 10 to 20 so from this one so the bond strength This one is the covalent.

ionic, hydrogen bonding, dipole-dipole interaction and the underbarous bonding. So and then we can sum the property toward the temperature changes one of the examples thermoplastics. Thermoplastics are usually linear or the branched polymers. The polymer chains are held together by the secondary bondings such as the van der Waals force or hydrogen bond which

When the temperature is raised, these weak intermolecular first become insignificant. As a result, the chain can slide past each other and the material will flow off-line the stress. This is why thermoplasty can be easily reshaped and recycled. when you had the end of the most sad

It's very different. In the thermostat, the polymer chain connected some primary cobalancing blending. So one example is the cross-relenting system. Because of the strong network, the material does not flow when heat. Instead, if the temperature is too high, degradation is awkward, meaning that the material break down rather than soften.

So it's not easy to rechain and recycle. At first glance, we might assume that all linear polymer behave as thermoplastics. However, this is not always the case. A good example is the polyacronitri. We call it PAN. Polyacronitri is a linear polymer. Looks like CN. cn.

but it does not behave like a thermoplastic. The reason lies in these strong intermolecular interactions. The PAN chain contains the nitrile functional groups which can form strong dipole-lipole interaction between the polymer chains. Because of these strong secondary flows, PAN does not soften and the flow easily upon the heating. Instead, at elevated temperature, it tends to cyclize, like this one.

and then degrade it, rather than melting like the typical thermoplastic. This unique property of the PAM is actually useful. For example, PAM, the main precursor for producing the carbon fiber equals tons of some new, where it is a strong interaction and the stability is essential.

then the after over the 300 celsius is close to 450 celsius it changed to the carbonized pan carbonized pan is widely used in the battery field so when the pan is carbonized it develops a graphite like this one structures which provide excellent electrical conductivity because

they have a conjugate structure and moreover their structural the mechanical property also is good because of these kinds of properties carbonized PAN is often employed as a conductive agent addictive helping electrons move more efficiently through the electrode Sometimes,

It can also be modified with sulfur used directly as active materials. This is particularly important in the lithium sulfur batteries. Carbonized PAN serves its role effectively. Sometimes they can use the freestanding fluid as an electrode. Carbonized PAN is quite...

very popular in the battery area. Now look at another example of linear polymer that is not thermoplastic. So already we talked about the cell rose. Cell rose looks like the linear structure made of the repeating glucose unit connected by the covalent font. But we know that it is not the thermoplastic.

so the flat load does not soften and flow when heat. The reason is the presence of many hydroxyl functional groups along the polymer chain. These groups form an extensive because of the intermolecular interaction hydroxyl bonding network between the chains. As a rigid the chains are tightly held together giving cellulose a rigid structure. But sometimes the cellulose nitrate like this one

it looks like some the some weapons like a bomb

Another interesting polymer, we can consider Teflon, already we know that polytetrafluoroethylene. It looks like a linear polymer, just CFCF, CFCF, the riptidine, the CF2 unit. But the fluorine is highly electronegative. We already know that in the periodic table.

F is a highly electronegative 4.0. It created a very strong carbon-fluorium bond, one of the strongest bonds in organic chemistry. This unique structure gives the PTFE several important properties. It is chemically very stable, chemically inert, meaning it does not react easily with the acid-base solvent and variable coefficient friction.

It means it extremely slippery and it also has excellent thermal stability allowing it to withstand high temperatures. So unlike the cellulose poly like cellulose the PTFE can be have a thermal plastic. However due to the is a very high melting point and the viscosity it is difficult to process with the conventional techniques.

Because of these properties, Teflon is widely used as non-stick coatings, and cookware as well as chemical resistance container, sealed electrical insulator.

but for the battery area, the PTFE is quite interesting they have interesting behavior PTFE usually process in the form of a fine powder

through the kinds of the some paste extrusion or dry casting the powder is changed the fine wheel the structure looks like they initially looks like the powder but then some applying the heat or the hose these kinds of the some structures change it like this one in the some the dry casting process which is popular in the solid state battery when

the ptf particles are stretched or deformed under a shear force. The polymer chain does not flow smoothly just they tend to split and like as aligned into the fiberless. Very fine thread-like structure. This phenomena is five relation.

this kind of a fibrillation behavior is highly useful and it provides PTFE with excellent mechanical strength, all structure, unique surface properties. This is why fibrillate PTFE is widely used in the membrane, battery separator, and the dry electrode, a lot of things in this way. So we can see the one of the good examples of

the pgfe for the drying process so i think the most of people doesn't know what is the drying process but usually when we make the battery electrode we mix carbon some some like active material powder and the polymer

binder and some solvent mixed together

and then so we can get some the gel like slurry is the liquid process wetting process and then we coated some metal foil. But then drying process means we don't need extra solvent so we can make some kind of battery electrode with the low cost

the eco-friendly because we don't use the expensive solvent. So let's watch this kind of the video made by the Fraunhofer in German.

demand for green technologies is increasing immensely. More and more electric vehicles are entering the roads, while myriads of electronic devices are consolidating their key status in people's lives. As a result, the efficient and environmentally friendly production of battery cells is moving to center stage. Especially during the manufacturing of the battery electrodes, state-of-the-art processes are very energy and space-consuming. As a suitable and efficient alternative, the Crown Hopper IWS has developed the Dry Coding Technology Dry Trick in order to overcome the recent challenges.

Today, battery manufacturing requires a lot of time, space, and monetary resources. The current practice is a complex wet chemical process in which active materials and other additives are dispersed in water or even in toxic organic solvents to create a so-called slurry. After depositing the slurry on an aluminum foil, the solvent has to be removed from the wet film in up to 100-meter-long dryers. In the case of organic solvents, elaborate solvent recovery is necessary.

In consequence, wet electrode coating causes high electricity costs. That's why Fronhofer IW has developed DryTrek. DryTrek is a dry, solvent-free, and cost-saving electrode coating technology. It eliminates the need for a drying line in the manufacturing process, thus saving considerable production space. This way DryTrek enables manufacturers to dispense with toxic and expensive solvents and save energy costs and space during electrode production.

In addition, DryTrek allows the use of battery materials that can hardly or not at all be processed by wet chemical methods. Precisely those materials that will be needed for future batteries with higher energy density. In consequence, DryTrek strives to support making battery cell production in Germany and Europe internationally competitive. Using an innovative powder to roll process, active material, binder, and conductive additive are mixed and fed into a calendar knit between two calendar rollers, which operate at different rotational speeds.

With a tailored set of parameters, a drive film is forming on the faster rotating calendar. Subsequently, the film is transferred from the roller onto a prime current electrofoil and an electrode coil is formed. Fraunhofer IWS has developed and realized several prototype machines that allow to code cathodes and anodes with process speeds of up to 10 meters per minute. In the Drive Protex Research Project, an interdisciplinary consortium has therefore addressed the question of how DriveTrek technology and its accompanying processes can be scaled up. Innovative solutions have been developed together with equipment manufacturers and cell manufacturers.

In addition to the actual coding process, the developments of the DryProtex Consortium include scalable dry compound production, equipment design, and process monitoring. We are convinced that our revolutionary DryTrek technology can pave the way for clean and efficient future battery electrode production. I think it is good for the understanding why do we need DryCasting in these sections. Bottoms come back to the polymer, the general catalysts.

Sometimes we need to dissolve the polymer, we need some solvent. So when an appropriate solvent is chosen, it comes from the strong secondary interactions such as the hydrogen boiling or the dipole interactions with the polymer chains. If the polymer is linear or the branched, these interactions may be strong in order to overcome the intermolecular force

holding the chain together allowing the polymer to dissolve completely. However, the situation is very different for cross-linked polymer. In this instance, the polymer chains are held together by covalent bonding. So solvent molecules cannot break these covalent cross-link. Inside the solvent, penetrate the network. Like the solvent molecule here.

So the cause the materials to swell rather than dissolve. The extent of swelling depends on the degree of coesed. So another thing, the right-lead coesed-linked polymer can swell the flamenzoic. For example is the super absorbent polymer used in the diaper. So which can absorb many times in the water.

The extensive cause in King's polymer shows little or no swelling because the dense network registers solvent penetrations. So there are some good some the table the solvent for dissolving the some kinds of the polymer. Now let's the closer look at the bonding and molecular structure of proteins using the amino acids as the basic building blocks proteins are made of the amino acid.

are their structure organized into several hydrochyl levels. One is the primary structure, it's a linear sequence of the amino acid joint by covalence peptide bond and the secondary things alpha helix structures. So these kinds of structures arise from hydrogen bondings and the tertiary structures looks like this one is over a three-dimensional folding of

a single polypeptide chain. This kind of bonding is destabilized by various interactions including hydrogen bonding, ionic interactions, hydrophobic effect and sometimes disulfide cobalent bond. And finally the cuttary structures like as weak intermolecular bond between the polymer so like as hydrogen bond Van de Reubert, force, ionic, the bond, and extra trap.

looks like here. That is the good example in the intermolecular interaction for the polymer structure. And then the last thing about the sterile isomerism in polymer, which refers to the structure of the arrangement of the substituents group among the polymer backbones. There are three main types. One is the isototic, syliototic, atartic called the random. Isototic conflagration, the substituents are generally

positioned on the same side of the polymer backbone but the syndiotatic configuration the substation periodically alternate or alternate disparate input of both side polymer chain atatic configuration is is definitely random so one of the good examples is a polystyrene syndiotatic like is the alternate both side like here highly regular and crystal structure i

iso-static structure is semi-crystalline, the atatic is irregular and amorphous structure. So depending on the stereoiso-rhythm, the physical property of polymer definitely different like the crystallinity, strength and the melting behind the air. So another example is the study-an. So all right we know that the one pole polymerization they have a cease and trans structure

among them the one thing in the one to polymerization considering just one thing is the natural bubble so I think it's good understandable if you find the so what is the polymerization of Italian at the time you can understand properly so like is another example is the eyes of friends also it has been multiple polarization

pathway and the stereochemical configurations like one-fold cease the polymerization that is the natural lava so it shows excellent elasticity with silence and trans that means trans and the same way it sees these kinds of things produce more crystalline

rigid structure so it is very different mechanical property compared to the natural lava and the nothing is one two polymerization is they can make different kinds of the polymer structure looks like here so I think is important for understanding the mechanical properties or a lot of the property and ionic the productivity for the polymer electrolyte could

pre-styling and amorphous. Pre-styling the reasons like this. The polymer chain arranged in a highly ordered regular pattern. This clothes packing read to higher density, higher melting point and great mechanical for it. Highly ordered regular pattern.

patterns. So one of example ABPE high-density polyethylene. Amorpose the polymer is arranged in the random disordered patterns. Because of these irregular packing, Amorpose polymer are generally rest-dense.

softer more flexible soft but then this kind of rigid

Most real polymers are not purely crystalline or purely amorphous. Instead, they contain a mixture of both regions. The balance between crystalline and amorphous domain greatly affects the properties like strength, toughness, flexibility, and optical clarity. Now let's consider the requirement of crystalline into polymers. One is the ordered arrangement in the

crystal retis. For polymer to crystallize the chain must be able to arrange themselves in the ordered crystal retis. This requires a certain degree of the regularity in the chain structures. So we can imagine like this Raman structure. The secondary post-bouldings within the crystal retis chain are had together by secondary intermolecular thorses.

such as bandarovirus interaction or hydrogen bonding. These kinds of interactions stabilize the crystalline region. And then sometimes usually they are semi-crystalline polymers. Some because of the defect, irregularities or chain entanglement prevent conflict ordering. so while the metals make containing only

part per million defect. Polymer usually have a much higher percentage of the defect. Finally, the crystalline regions in polymers usually characterize using X-ray diffraction or X-ray study, which allows us to identify the degree of order and the crystallinity in the matrials. And then the effect of polymer structure, temperature and solvent.

the crystallinity the polymer crystal are highly ordered arrangement in the segment so already known that stabilized by secondary bond if the this weak wound are disrupted by structural liability heat or the solvent the degree of crystallinity decrease is change directly affect the polymer structure

strength density and the melting behavior and then the temperature as the temperature is rise the crystallinity bonds begin to collapse that means the melting points so and then the solvent already you know the solvent can distribute polymer polymer bond dissolve the polymer and then perky side group prevent crystalline alignment like this one and you like the arrangement

Hinder the formation of crystal. Functional growth can increase tendency crystallization.

And then the effect of crystallinity on mechanical fluoride. We already know that higher crystallinity means stronger than mechanical fluoride. So moreover, according to the discarded equation, the density is quite similar to the crystallinity. So we can see the example high density polyethylene, the raw density polyethylene.

the rhenia and rule density polyethylene LLPE. look at this table there are three different type of polyethylene LEP medium than LEP high density polyethylene the medium density means LLEP

as the density of polyethylene is increased, degree of chrysalinity also increased. Along with this, we can observe the increase the melting point looks like here. Hardness also increased, a lot of mechanical properties also increased. That means the structural arrangement of polymer chain directly influences both chrysalinity and mechanical properties.

melting point. So already we talked about the crystallinity influenced the machaic properties of polymers. The polymer chain or regular packed in the crystal area can support the stress. Close and regular contact means greater secondary pose. Crystalline significantly increases strength and the rigidity. So already know the higher crystalline polymer.

stronger, tensile, modulus, more rigid. So let's look at this example. Sterile, regular polypropylene is static or sinuotactic, hard and rigid plastic. But the 8-tatic polypropylene is regular. It's quite soft and sticky. Optical property also the crystallinity influenced the transparency and some trans...

When the light passes between the two phases with different refractive indices, the sum of the bases scattered at the interface, if the dimension or the discontinuity are comparable to or greater than the wavelengths of the visible light. So one of the examples is eyes transparent, bottom snow just white. So in that case,

So the snow appears white because the white is scattered at the many interface between the air and the ice crystals. In the polymer, it's a similar principle of light. Crystalline the region are denser and therefore they have a higher refractive index than the amorphous region. So this mismatch is in the refractive index with the sceptamine making crystalline polymer appear transcurrent.

Complyfully, the amorphous polymer by contrast can be transparent. That is the important thing because there is no significant interface to scatter visible light. So one of the exception, polyformatyl one-pentine is the crystalline polymer that still appears transferred. This is because the refract.

in this depth of the crystalline and amorphous regions are really identical minimizing scattering. Also the size of the crystal also play the important laws. If the crystals are smaller than the wavelengths of the visible eye, scattering is great greatly reduced and the polymer appears more transparent. Or another thing if we add some kinds of the fiddler

sometimes the phylla can also introduce scattering center often reducing transverse. And then let's take a look at a special type of polymer structure called expanded chain crystal. So when the polymer crystallize under external flow or the drawing,

The floor tends to disentangle the chain and align them in the direction of the structures. Instead of forming a corded chain, the polymer developed the fiber structures known as extended chain crystals. Already we know the fiber structure means the PTF with the structures. And also the polymer chain aligned parallel when I go to the distance. We're going to change super strong there.

the fibers we can make it. Another important factor in the produce extended chain fiber is processing method. When the fiber forms from the relatively diluted solutions, the polymer chains this entangle the more easily catalyzed the better, resulting in the improved crystallinity and the stronger mechanical

properties so that is about the crystalline and the amorphous polymer the section bottom is quite contained the very complex some the regions but I'm just we know that the one of the important things crystalline has highly ordered structure so their metallic property is very tough like the rigid structure but amorphous structure

they have a random and disordered structure so it is flexible and the soft that is the the key the concept of crystalline and the amorphous that about the magnetic properties of optical property so we already know that the crystalline structures they have a some the higher the refractive index so crystalline polymer it looks like this one but on the amorphous polymer

it is quite the transparent material but then we can control that the size of the control of the size of the crystals or adding the filler there are some a lot of things that is the all of the some basic polymers it's related to the important to the concept but um so to understand the polymer so i recommend to

take some polymer class it will be harder to understand all of the things like is polymerization techniques or the polymer composites or the designing polymers the characterization polymers a lot of things in the polymer engineering some kinds of the class thank you