Equipment § Thermomechanical Analyzer
Thermomechanical Analyzer (TMA) is a kind of thermal analysis technology. It mainly uses the linear variable differential transformer (LVDT) inside the instrument to measure changes in size (linear or volumetric). The principle of TMA is to place the test object in a device that can be heated, press the probe with a specific force against the object to be tested. And select the program and rate of temperature change to obtain the dimensional change and temperature, time and mechanical load of the material. The relationship between. The function of TMA is to measure: 1. Coefficient of Thermal Expansion, CTE; 2. Glass Transition Temperature, Tg; 3. Delamination Temperature; 4. Thermal Stability 5. Softening point temperature Softening Point.
Safety § Latex gloves (Part 1)
In the resin manufacturing industry, we often contact many highly infectious chemicals. To protect ourselves and maintain our health, most of us wear latex gloves to reduce the risk of infection. However, many colleagues have reacted. After wearing latex gloves, it will still cause allergic symptoms, redness, swelling, and peeling of the hands, and itching is unbearable. However, are the allergic symptoms you are experiencing due to highly infectious chemicals? The latex gloves we wear every day have been proven to prevent and block infectious diseases or microbial infections, but they can also cause allergic symptoms.
Since latex products are made from the rubber tree sap, some compounds may be added to the sap of the rubber tree during the manufacturing process. The compounds in latex products or the proteins contained in latex may cause allergic symptoms. In contrast, the lubricating powder in latex gloves may become suspended particles when the latex gloves are removed, and if inhaled, it will cause respiratory infections.
According to the "Labor Health and Safety Newsletter - Issue 28" of the Institute of Labor Safety and Health, latex allergy can be divided into three types: 1. Irritant contact dermatitis, the most common latex allergy symptom, is usually dry and itchy skin on the hands. The reason may come from using latex gloves or because of the products and chemicals we touch. The symptoms are caused by (1) repeated hand washing, (2) incomplete drying of hands, (3) highly infectious chemicals, and (4) lubricant powder contained in gloves. However, irritant contact dermatitis is not an actual allergy symptom. 2. Allergic contact dermatitis is caused by exposure to chemicals added to harvest, process, and manufacture latex. These chemicals cause ivy-like symptoms on the skin, a rash or blisters within 24 to 48 hours of exposure, and spread through contact. 3. Latex allergy is the most severe allergic symptom. The proteins in some latexes may cause allergy symptoms. Although the dose of exposure to cause allergic symptoms is unknown, even exposure to low concentrations can cause an allergic reaction in some people who are already allergic.
Knowledge § Tg is not obvious?
When measuring Tg, what is the reason why Tg is not obvious? How to solve it?
The most common reason for an insignificant Tg is that the internal stress of the material is not released. Stress is usually relieved by annealing: heating the test piece to a temperature near Tg and then slowly cooling down, the Tg can be displayed. The Tg itself is not obvious for some materials because of the high degree of crosslinking or high crystallinity. MDSC can be used to improve the analysis ability.
產品介紹 § NA456
EPOWIDE® NA456 is a one-component solvent-based epoxy resin adhesive for metal products and composite materials. EPOWIDE® NA456 can be used for a long time, easy to process at room temperature, and hardening at high temperature. This product has excellent thermal shock resistance and toughness, effectively reducing the stress caused by temperature changes, thermal expansion, and contraction on the joints. After hardening, the resin has high mechanical strength and high-temperature resistance, which can adapt to the use of general industrial products.
Activity § Table tennis game
Everwide Chemical's second table tennis competition:
Men's first place: Ming-xu, Li, second place: Jian-zhong, Li, third place: Wen-chao, Shi; women's first place: Ming-xiu, Lai, second place: Miao-ling, Lin, third place: Yu-zhi, Ai.
Congratulations to all the contestants above!
Living § Man old, book yellow
A while ago, to buy an instrument analysis, I often went to the auction website to try my luck to see if there were any suitable books. After a few times, it has become a habit. When you have time, you can enter fixed keywords, such as "polymer," "plastic," "composite material," "ink," "adhesive," etc., and enjoy the thrill of surprises.
I go to auction sites to find books because many books are out of print and not sold in bookstores. A few days ago, I bought "Experimental Methods of Polymers (Hardcover)" edited by Jing-he, Xue. The online auction price was only 120 yuan, which was unimaginably cheap. The new book was about 400~500 yuan. I was delighted when I received the book, it looks as good as ever, and the original owner probably has not turned it over. However, when I turned to the inner page, I was shocked; the paper inside was yellowed. I read this book when I was in graduate school, and I lent it to others and never reread it. In the same situation, there are many books, such as "Complete Book of Adhesives" edited by Jing-he, Xue, "Polymer Physics and Mechanical Properties" edited by Hu-de, etc. These books are like old friends to me. I miss the time when I read them, eager to meet them again. Today I casually flipped through the book "Experimental Methods of Polymers," only to find that it was published 28 years ago (1980), and I read this book 16 years ago (1992). The memory is the same as yesterday, but I am a little older, and you are also a little yellow.
─Author: Dr. Ming-xu, Li, Everwide Chemical
