In the early 1990s, the Shanghai Ac

In the early 1990s, the Shanghai Academy of Architectural Sciences developed high aspect ratio gypsum whisker (up to 100) and adopted the hydrothermal positive pressure technology, but it was only the laboratory result, and could not persist. And I didn't really understand his role or his importance. After that, northeastern university and Shenyang Angli new material company produced Gypsum whiskers with a aspect ratio of about 20 by hydrothermal method, and used them to increase the strength of nylon, with some success, and developed a process line set up an annual production line of 600 tons. Wu Gong Da has also developed a patented technology for making Gypsum whiskers. Some experts in Shanxi and Xianyang have also conducted research. In Nanjing and Shandong, using the principle of atmospheric pressure dissolving and recrystallization, chemical gypsum and natural dihydrate gypsum have been experimented to produce some dihydrate fiber calcium sulfate, the ratio of fiber length to diameter is only 20-30, most of which are fiber bundles. Several drying and dehydration methods have also been tried. Experiments with these fibrous calcium sulfate in paper mills have not yielded the theoretical results. According to the relevant information, the international trade name of Gypsum whiskers is "ONODA-GPF" , which is basically made by hydrothermal method, semi-aqueous and anhydrous.