Study On Ultrahigh Molecular Weight Poly (Vinyl Alcohol) And Its Pilot Plant Design

This is a self-suggested research project, proposed according to the guideline of national "9.5" layout and 2010 long-term development plan. Ultrahigh molecular weight poly(vinyl alcohol) fiber is of a very important high performance fiber, which has a high tensile strength and modulus and can find many potential applications in national defense, aerospace and construction industry. So far this kind of high performance fiber is monopolized by Japan and embargoed to China. Otherwise, the application of high performance poly(vinyl alcohol) fiber can also promote the development of relative industries. So the research on high performance poly(vinyl alcohol) fiber and its industrialization have both economic and society benefit.During the study, a great deal of experimental schemes were compared and the better one has been selected:1. Unique monomer purification technology assures to get the high purification monomer, which is a basic requirement for synthesis of high molecular weight poly(vinyl alcohol). The successful monomer purification technology has established a sound fundamental for the completion of this project.2. The ultrahigh molecular weight poly(vinyl alcohol) was prepared by a seeded emulsification polymerization. In this study, an effective emulsion polymerization procedure has developed. During polymerization, the low temperature redox initiation system and low initiator and emulsifier content has been used. The final polymer has a very high molecular weight and narrow molecular weight distribution, which is a required raw material for spinning high performance poly(vinyl alcohol) fiber.3. AH chemicals used in this project are made in China, so it is easy to industrialize and the low product cost is in favor of its competition in international market.4. Based on a large amount of laboratory and pilot plant scale experiments, it can be concluded that the technical approach for ultrahigh molecular weight poly(vinyl alcohol) is reliable and this study offers a set of important technical parameters for the industrialization of high performance po!y(vinyl alcohol) fiber.