Preparation Of Antistatic Acrylic Modified With Nano-Metal Oxides

Polyacrylonitrile (PAN) fiber has a lot of good properties, such as fluffy texture, soft handfeel, low density, good resilience. It was widely used in both industrial and civil fields and it was also known as " synthetic wool". However, its inherent hydrophobic and insulating properties make itself easy to produce static electricity, so it was greatly significant to study and develop a kind of PAN fiber with antistatic properties.Currently, two main kinds of antistatic agents are utilized to modify the property of PAN fiber:one is carbon black filler, which has high oil absorption. It was very hard to disperse and needs a big addition. The thus-produced black PAN fibers restrict the area of its application. The other is nano-metal oxide, used to produce white and light-colored fibers. The development trend of antistatic acrylic is to produce light-colored fibers and inexpensive (low conductive filler content). Also the lasting antistatic effects and the good spinnability and mechanical properties of fibers should be considered.Nano powder has high surface energy and activity, so it was easy to generate agglomeration and lose the unique property and excellent performance of nanomaterials. Therefore, it was necessary to utilize an appropriate dispersion process to disperse nano metal oxide used in experiments. This paper selects four kinds of nano-metal oxide as the antistatic agents of antistatic acrylics, namely, nano-ZnO, AZO, ATO and ATO coated BaSO4. Firstly, we adopted best dispersion process through which the dispersed nano-ZnO, AZO, ATO and ATO coated BaSO4powder’s aqueous suspension has better stability:we select FCY (2%wt.) from other dispersants as our dispersing agent by observing subsidence phenomenon. The particle size of nanoparticles in suspension is under1μm and can meet the requirement of wet spinning process.Secondly, this paper, by directly adding aqueous suspension of nano-metal oxide, prepares polyacrylonitrile dope, which was easy and practicable. Moreover, this method can make nano-metal oxide well dispersed in dope. Through the polarizing microscope, we can observe that nanoparticles under2μm in PAN dope can be well dispersed and that no obvious agglomeration phenomenon happens, so it can be further applied to the wet spinning experiment. The rheological test shows that as the sheer rate increase, PAN dope was a shear-thinning fluid accord with non-newtonian fluids’rheological behavior. As temperature increase, the viscosity declined because of the macromolecule in PAN dope faster motion. As nano powder adds, because of the plasticization of dispersing agent and water, the viscosity of PAN dope declined. According to this result, spinning process can be appropriately adjusted.Last but not least, wet spinning process helps spin antistatic acrylic modified by different kind of nano-metal oxides with different content, thus determining the spinning process. This paper conducts a test on the volume resistivity and washability of spun fibers. Its results show that when ATO is the antistatic agent, the volume resistivity of fibers is the lowest, between about108-109Ω·cm. Therefore, modified antistatic fibers have better antistatic effects.