改性聚乙烯醇新型纺丝工艺分析.docx

STUDY ON MODIFIED POLY(VINYL ALCOHOL) FIBERS PREPARED BY A NEW KIND OF SPINNING
Abstract
Poly(vinyl alcohol) is a multi-hydroxyl polymer with excellent mechanical properties, thermal properties, moisture absorption, corrosion resistance, weather resistance and interfacial bonding properties, which is the raw material of vinylon. However, the multi-hydroxyls of PVA make its melting point close to its position temperature. As a result the thermal processing of PVA is difficult. So PVA fibers are usually prepared by wet spinning. However, plicated processing, heavy pollution and poor mechanical properties of wet spinning limit PVA fibers applications. Therefore, it has great theoretical and socio-economic values to explore a new green spinning process and preparing high-performance PVA fibers.
In this paper, a metal plexing agent M, environmentally friendly plasticizer A and polyether plasticizer B formed pound modifier. I added it to raw PVA to prepare modified PVA. By FTIR, DTA-TG and XRD, this paper studied the effects of different contents of modifier on hydrogen bonding, thermal properties and crystallization of modified PVA. By capillary rheometer, this paper studied the effects of different contents of each modifier, processing temperature and shear rate on the rheological behavior of modified PVA. I spun below the melting point of the modified PVA, which is called quasi-melt-spinning process. By polarizing fiberscope, FTIR, XRD, DTA-TG, I studied the surface morphology of as-quasi-melt-spun fibers of modified PVA, changes of hydrogen bonds, crystallization and thermal properties. By a drafting equipment, I studied the effects of drawing temperature, drawing speed and the content of metal plexing agent M on breaking elongation of modified
III
PVA fibers, and thus got the best parameters of drawing process.
The results show that: adding a metal plexing agents can improve the thermal stability of the M-modified PVA, lower the melting point. It is not contrib