Experiment § PU moisture hardening-protective glue
Moisture hardening reaction.
TDI, MDI, HMDI, etc., in the state of excessive isocyanate (NCO/OH>1), react with the reactive group-containing OH functional group. The resulting compound is coated on the object's surface to be coated and is removed by moisture in the air and hardened to form a film (Figure 1). The properties of the film are adjusted by adding some additives or non-reactive diluents to adjust the hardness and toughness. When coated on the aluminum substrate, it has the function of protective glue, which is easily peeled off with fingers after processing. As shown in Figure 2, the protective adhesive is coated on an aluminum substrate, and a film is formed in about 20 minutes. After five hours, the film is torn off the entire surface. When baked at 150oC, the film will not stick to the aluminum substrate, and the whole film is still peeled off at room temperature. It is convenient to use this protective glue in baking paint or composite materials.
─Author: Mr. Rong-xin, Lin, Assistant R&D Engineer, Everwide Chemical
Environment § Forever subject - environmental protection
Everwide Chemical attaches great importance to the concept of green environmental protection: in addition to the common recycling of iron and aluminum cans, special bottles, paper, etc., the used solvents are distilled and reused in the factory; recyclers collect the empty barrels of raw materials. It is sold after cleaning; the packaging and containers of the products are paid to the Recycling Fund Management Board to assist in recycling; business wastes are cleared and transported by qualified processing operators. Our products must comply with laws and regulations and do not contain prohibited or restricted substances harmful to the environment. Relevant colleagues bring the kitchen waste from daily life home to feed livestock, and trees are trimmed on garden roads. We also drag them back to the factory, crush them as compost, and improve the soil. To the earth, we humans are just passing by at a glance. To balance the use of resources and ecological maintenance is the work that we humans must continue to work hard.
Knowledge § What is a light absorber?
Simply put, a UV absorber is a chemical substance that absorbs the energy of light and converts it into heat energy. This characteristic of light absorbers is used in cosmetics, plastics, coatings, etc., to absorb higher-energy light (usually UVA, UVB) to avoid aging reactions. The main light absorbers are Benzophenone and Triazine, and other systems account for a smaller proportion. Light absorbers are also developed for inorganic systems, which have better durability than organic systems.
Living § How much do you know about temperature (1)
Today is my 38th birthday, the mother of an eight and three-year-old. On this beautiful autumn weekend, some of our parents and children came to Chenggong Elementary School in Pingding Village, Linnei Township, Yunlin County, to conduct a science experiment class.
This school is quite well-known in Taiwan. It is the only place for the purple monarch butterfly to migrate northward. After Chenggong Elementary School, the purple monarch butterfly passed through brave Formosa High for a difficult journey. We wanted Yun's mother to be the school nurse, so we borrowed the school's auditorium for a two-hour temperature science experiment class. Today's content is exciting! We first ask the children to draw a thermometer and carefully observe it before describing it well. Some children will think about it before drawing, and some will concentrate on drawing the thermometer in their minds. Studying science is to learn in fun, and it is more effective to present it in a life-like way. The weather is good today. We prepare cloths of various colors (white, red, green, black) to wrap the thermometer and place it in the sun to observe the temperature changes. After an hour, we can see the temperature change from the thermometer's scale.
─Author: Ms. Miao-ling, Lin, R&D Engineer, Everwide Chemical
