Experiment § Water-resistant modified silicone adhesive
Most of the single-fluid moisture-curing RTV1 on the market are silicone adhesive. The advantage of silicone is that it can work at a temperature of -40~200°C and has excellent water repellency. The disadvantage is that the adhesion is weak, and the adhesion to metals and plastics is mostly less than 20 kgf/cm2, so there is a modified silicone (Modified silicone, MS). The adhesion of modified silicone adhesive to many substrates is greater than 20 kgf/cm2, but it has a higher water absorption rate than silicone adhesive, so we developed FS332BL67 to overcome this shortcoming. FS332BL67 has water resistance and high adhesion. The PC was adhered with FS332BL67, then immersed in water at 80°C for 5 days, and then subjected to the shear tensile test (Figure 1). The reasons for the decrease in strength of the adhesive in this test are as follows: 1. Moisture diffuses between the resin and the substrate interface, replacing the original bond between the resin and the substrate. 2. Immersion in water at high temperatures will cause the hydrolysis reaction of the ester group in the molecule, and the molecular chain will break and lose its strength. 3. The resin will swell and become soft when it absorbs water so that the tensile force value will decrease. FS332BL67 overcomes these weaknesses and exhibits good adhesion to substrates (Figure 2). It also showed no obvious decay after being immersed in water at 85°C for 72hrs (Figure 3). FS332BL67 has no tin catalyst added, can work at -40~100℃ temperature, and can be used for sealing grooves in the optical electronics industry. You are welcome to contact us.
─Author: Mr. Zhe-Yong, Lin
Activity § Plant a small seed, cultivate a big dream
The Chiayi Forestry Bureau promotes the adoption of afforestation plans by enterprises, and Lucidity enterprise invites suppliers such as Everwide to adopt two afforestation sites in Tainan jointly. In total, about 8,000 trees of sweetgum and other tree species were planted by hand (Figure 1，2). By planting trees, the earth can return to green space. If you need to adopt, please click this link：https://chiayi.forest.gov.tw/0000540 Cooperate with the Creation Foundation to support the vegetative care service, and purchase public welfare rice dumplings and dried fruits and vegetables to distribute to colleagues as festive gifts (Figure 3, 4). Set up barrier-free toilets and parking spaces to provide convenient spaces for people with disabilities, and treat others in a friendly environment starting from you and me (Figure 5).
Knowledge § Can double bonds be photocured?
Theoretically, compounds with double bonds can be radically polymerized by photoinitiators or thermal initiators. The free-radical polymerization of some double bonds is very fast, and they can react with themselves quickly during the exposure process. Acrylic is a typical example. Some double adhesives polymerize slowly with themselves because of the substituents and are not suitable for photocuring alone. For example, the structure of a vinyl ether. Systems that polymerize very slowly on their own can sometimes be used for copolymerization. For example, a mixture of high levels of acrylic and less than 20% vinyl ether can be fully cured. This example shows that whether a compound with double bonds can be photocured depends on the monomer structure and formulation composition.
Living § College Students' Choice
During the first semester of my senior year, I found that I had almost completed my credits. I don't want to have nothing to do every day, and I have some small ideas for the future, so I choose to go to the factory for an internship next semester. I submitted an internship application and came to Everwide after passing the interview. I found that Everwide is very special. It is not like an ordinary company, and there be many learning courses here so that we can continue to absorb new knowledge. In addition, there are many fun activities, such as beach cleaning, tree climbing, and other experiences, so we can relax and live after work. I got three books on the first day I arrived at Everwide, I was a little annoying at first because I had to write reading feedback, but after I read the content of the books, my mind changed. Because the book's content is really interesting, I read each book very quickly, and after reading it, I also thought about issues that I might not have thought of before and even overturned my old thinking. In addition, I also learned a lot of professional knowledge and life philosophy through the intern courses arranged by the company. In the beginning, because my major was unrelated to chemistry, I was worried that I could not understand it. Fortunately, the lecturers explained it in a simple and detailed manner. In addition to the lectures, the company will also arrange super interesting hand-made activities to know more about the reasons for chemical bubbles. What I find most useful is that the lecturer will share his thoughts on the workplace and research institutes, allowing me to think more profoundly and face plans. I think the most significant gain should be that my inner thoughts become broader and more mature.
─Author: Miss. Wan-Xiang, Lin
