 Hello everyone, today I clearly deny any will be presenting our capstone project on a topic that is both exciting and innovating and the topic of our capstone project and our scientific paper is the development of transparent wood technology as a glass substitute. So in recent years there has been no going concern over the environmental impacts of the current building materials such as concrete and steel and researchers have been examining new alternative substitutions for the current building materials to make them more eco-friendly and sustainable. One of such materials is wood however wood has its own legs it is not transparent and here comes our research we have been examining wood fabrications that would result in wood transparency but before moving on to our experiment part let's just briefly go over why do we need a substitute for glass. So transparent wood for the advantages transparent wood is better biodegradable material instead of shattering it bends or slippers it's five times more thermally efficient it and the protection results in low carbon emissions however it has also its disadvantages when using high-scale protection epoxy resin is used and it's not environmentally friendly and it is difficult to mass produce because its component is produced in different type frame for the glass it is easy to maintain with basic cleaning tools and it's non-glasting obviously but it produces heavy carbon footprint and it's not as thermally efficient as wood. So before again moving on to the fabrication part let's talk about the structure and composition of wood in order to better understand what we did. So here's our wood it's kind of similar to picture here the outer the first two layers are called outer bark and inner bark the outer bark is there to protect our wood from the outside world so it's losing moisture or drying out or insects in general and the second part is the inner wood its main purpose is to deliver results mineral to the rest of the wood. Next is the sap wood it has more cellulose content it is softer and has less density as opposed to hardwood which is the darkest part of the wood and it has lignin we will talk about lignin shortly but to emphasize what I'm going to talk about let's just know that lignin is responsible for the dark color of the wood and for the mechanical strength and stiffness so basically more lignin means darker color and the vascular cambium is basically the boundary between each layer and the central part is called pith which is the oldest part of the wood and it has tendency to crack for the compositional part as I've said wood is composed of cellulose and lignin however it has also hemicellulose and small content of other extractors and inorganics while cellulose and hemicellulose are colorless in the range of visible light lignin is again responsible for the color because of its absorptive properties 80 to 95 percent of the UV light that is reflected in our wood is absorbed by lignin and it gives our wood the dark color so lignin is the second most abundant organic polymer in earth and it is the largest natural source of aromatic monomers and because of its wide range of properties it can be used in a variety of industries not only in construction it can be used as a biofuel it can be used as a bioplastic as a asphalt pavement modifier can be used in wood dressing and tissue engineering and as a substitute for lignin and now I will talk about how to modify lignin to achieve transfers so the basic chemical process includes two steps the first step is the lignification meaning the removal of lignin overall so there are many the lignification methods used in industries so first one is popular linear fabrication sodium hypochloric solution solar assisted chemical brushing fabrication by polymethyl methacrylate biobase lineman acrylate monomer method so basically there are many methods and we have considered different drawbacks and advantages of using each method and decided to go for solar assisted chemical brushing so why did we choose this method first of all it is it is relatively environmentally friendly compared to the other method that I mentioned it has low chemical usage meaning there are no very few chemicals are required to conduct this process there is no requirement of using high temperature a very good advantage is that it does not modify cellulose meaning it only modifies the lignin part and does not harm the other polymers existing in wood there are less waste and toxic gases in this process however this process also has its drawbacks for example although I mentioned that this method is a relatively environmentally friendly use of hydrogen peroxide may generate harmful byproducts if the experiments are not conducted carefully compared to the other method that I talked about in the previous slide this method is relatively slower and the effectiveness of this method highly depends on the type of wood that is being used so the actual process of solar assisted chemical brushing is the following first of all 0.6 to 1.5 millimeter thickness wood samples are being immersed into sodium hydroxide solution after both they are being immersed into hydrogen peroxide solution so in the next stage UV light is required to continue the experiments in our experiments we used direct sun rays to be more environmentally friendly but in our building papers we can find that UV lamps are used as well and after exposing to sunlight for one hour the wood samples are put inside ethanol for five hours to remove additional chemicals from the wood samples and receive the pre-transparent delignified wood the next stage after delignification is called polymeric impregnation or polymerization from the image we can see that this part is before delignification and the right part is after delignification so before delignification left part is before polymeric impregnation and the right part is after polymeric impregnation so the delign since aligning is a polymer it is feeling the inside skeleton of the wood meaning that so is the base of the wood base skeleton so after delignifying the wood there are many holes and pipes left inside the wood structure so in simple words polymerization is a process of filling in that inside structure to maintain to increase the flexibility optical properties or water resistance and other physical properties of the wood so the wood will be stronger and lose its thickness before that was because of the delignification process so the basic polymerization polymerization is the following epoxy resin which is a polymer is being mixed with it's cure-engaged with at ratio one through two afterwards the wood samples the already delignified wood samples are immersed are being brushed with epoxy resin and used under atmospheric pressure for 10 minutes so basically it is advised to use vacuum pressure for this process however since we do not have a vacuum chamber equipment we used atmospheric pressure and afterwards we used press to to merge so afterwards after that press the wood samples are cured to remove from the pressing material and leave this now going to talk about the actual experiment we did and the results now coming to the part that we all been waiting for our experiments and results so we conducted our experiment with the process that Hyde mentioned earlier so we chose various types of wood from pure apple oak and some nut trees and as you can see each of them has different color also different thicknesses so the first picture you see here is the wood samples after being immersed in hydrogen peroxide and left in the sun to be delignified so we did the delignification two ways first way was brushing them with hydrogen peroxide and the second way was immersing them in the hydrogen peroxide bath however we didn't see significant difference between the two ways so as i mentioned the picture or first picture was them in the hydrogen peroxide bath and the second picture is them after being dried and ready for the second round of the identification this is our samples after being delignified and as you can see decolorization has already taken place from the first actual wood product that we had and the right hand side is the woods after a delignification also you can see that darker wood has also gone the delignification and decolorization lighter ones as well and the thickest one as well however due to contrasts it's not very visible so we wanted to see how much transparency they have achieved and as you can see here we have the darkest samples of our wood and a significant difference is visible after delignification we wanted to see if our wood was has achieved transparency and if we could read through our samples so we put our our sampled wood on paper and tried to read through them and as you can see both samples the light color and dark colored have achieved significant amount of transparency the darker colors are more readable however the lighter colors are more blurry the reading is more blurry and translucent we have an issue here with a darker colored wood samples because they require more delignification and it's time consuming and if it was in the industry and fabrication this would be a constraint that's why we decided to omit the darkest and thickest samples of wood and work with the lighter samples after the delignification process was done we saw that our wood has achieved transparency and we could assume that polymerization was not required however polymerization is also important because lignin is also responsible for the wood's stiffness and mechanical strength so the first sample here you see all of them are from the same batch of wood and the first sample is the initial state of wood without being delignified nor polymerized the second picture here is the wood after delignification while the third picture here is the polymerized wood so the right hand part of the wood is only delignified while this part is already polymerized and you already can see the significant difference between them so coming to our constraint and future works so we faced a few constraints the first thing was the unpredictable nature of sunlight and the low solar intensity since we conducted our experiment during springtime next was not having required equipment such as vacuum chambers and the press so we conducted our experiment atmospheric pressure atmospheric atmospheric environment and the next was that the wood samples that we had were hand prepared therefore they were with a rough with a rough edges and not as smooth as we wanted them to be and next was the absence of material science laboratory coming to the future work we want to extend our delignification and polymerization processes we want to test with various types of wood with the reports that we have read they used balsa wood however we wanted to use wood that were available in Armenia and last but not least testing for material properties of the wood here are our acknowledgment we would like to thank our engineering department our program chair and the dean moreover we would like to thank our supervisor Hirachi Okocharian who was there with us from the first day for his constant support and here are our references that we have used thank you first off it's quite a complex and big project I think you guys did a really great job putting all the bars together because there are different aspects involved in this what I'm curious to know is the thickness of the samples you used from the original woods until you got your last result so we used our sample of various thicknesses ranging from 0.6 to 1.5 0.6 to 1.5 millimeters what I would be curious to see actually a result in sort of a graph trying different different thicknesses processed throughout the same amount of time and then the same thicknesses processed until you reach full transparency sort of saying and then see the penetration depth or the absorption rate kind of a graph and see how that how the thickness of your sample gets affected within the process that would be really interesting to see I think yeah in our future works that's great but we have already tried our we already tried samples on thick woods as well however we mainly focused on the thick within ones because in the fabrication in the industry we use in the future the lack of time and the multiple delignification is an equipment yes equipment also were a problem so that gets me to my last question do you think the time needed to to get to the end result is the bottleneck in this whole process like the most challenging aspect the most challenging processing stage is it getting some specific material or having sufficient sunlight or some pressure chamber I mean I saw the pressure chamber is a challenge but say you have you have all the equipment all the material you need what would be your opinion what would be the bottleneck in the whole process so basically it would be very helpful to have some kind of equipment that would absorb the physical structure of the wood how it changes up to the delignification step after the polymerization step because we are working everything we did we only usually because we couldn't we didn't see any changes to the micro-stopic level that was definitely good thank you uh can I ask this question really quick question would you call this plastic wood what kind of scientific equipment do we have used at all because if I couldn't see any data produced what kind of transparency we have achieved I mean the mechanical properties how have you measured yeah that was our concern one of our concerns because we didn't have equipment I mentioned that we didn't have the vacuum chamber and also press to conduct and we didn't have materials science laboratory to see these properties and do our research even to do our experiments even deeper to see and have better results so we just went with the equipment that we had in our chemistry lab for example you said we had significant increase decrease in luminosity but you're engineering sciences students if you have the equipment to measure these things what kind of an equipment would you use to measure this or what kind of setup would you need to actually quantify the transparency that you have achieved so first of all we will have a look at the changing physical structure after each chemical process we did so that would help us to understand whether polymerization work effectively whether delignification work effectively so all of our conclusions were based on visual effects that we noticed so what tool would you use to replace the visual impact with numbers so basically a very important thing to measure is the temperature effects are measuring so we need to understand how much heat is lost after it is being transferred to the transparent wood so basically there are cameras that capture the structure in a microscopic level if I'm not mistaken they are they are called SEM cameras but we don't have that in Armenia actually I can see the I showed the image yes and this will be the result we would have achieved if we had the camera just another microscope in Armenia one of the chemistry institutes okay so you could have done better researching what kind of scientific equipment is present in Armenia the guy next to me has a cube chamber mechanics institute a few hundred meters down the road has enough equipment to measure mechanical properties my advice would be just look around what you are missing and try to find out okay I just wanted to say that if you could have obviously probably a spectroscopic matrix with the transparency to see what the experience would be achieved