Effects of interface affinity on the rheological properties of zinc oxide nanoparticle-suspended polymer solutions

Abstract

The effects of the interface affinity between the nanoparticle and polymer matrix on the rheological properties of nanoparticle suspended-polymer solutions were investigated. Two polymers, polar polyacrylonitrile (PAN) and nonpolar polystyrene (PS), were selected, and the cosolvent was N,N-dimethylacetamide and 0.1~5 wt% of polar ZnO nanoparticles in the polymer were used. The inclusion of ZnO notably increased the viscosity (η') of the PAN solutions, even at such a low loading level of 0.1 wt%. A maximum value of η' was observed at a 1 wt% of ZnO content. On the other hand, the η' of the PS solutions decreased with increasing ZnO content. Both the PAN and PS suspension systems exhibited a notable decrease in η' above a critical ZnO content.Although the PAN solutions showed a lower loss tangent (tanδ) at higher ZnO contents, the PS solutions containing > 2 wt% ZnO showed higher tanδ above a frequency of 2 rad/s. On the Cole-Cole plot, the PAN solutions did not give a single master curve depending on the ZnO content. However, the PS solutions showed little scattering from the master curve of a slope of ca. 1. ZnO increased the relaxation time of the PAN solutions but decreased the relaxation time of the PS solutions.

Electrospinning of poly(ε‐caprolactone) solutions containing graphene oxide: Effects of graphene oxide content and oxidation level

“…The polar–polar interaction between ZnO and polyacrylonitrile (PAN) chains causes the viscosity to increase, whereas the repulsion between nonpolar PS chains and polar ZnO causes the viscosity to decrease. Agglomeration of ZnO nanoparticles above the critical amount of ZnO (1 wt%) decreases the viscosity of PAN solutions as a result of a reduction in the interacting sites .…”

Preparation of 3D crimped ZnO/PAN hybrid nanofiber mats with photocatalytic activity and antibacterial properties by blow‐spinning

“…The discrepancy between fiber diameter and solution viscosity for the sample containing 5 wt% is explained by greater air traction during fiber formation that overcomes the effect of higher viscosity 58 . When the ZnO NP content is low, the strong interaction between the polar ZnO and polar PAN molecular segments limits the movement of polymer molecular chains in the suspension, resulting in the rising viscosity 59 . Upon further increase in ZnO content, a small amount of Zn 2+ diffuses into the PAN molecule to neutralize the negative charge on the surface of the PAN nanofibers.…”

Mechanical and UV‐shielding properties of in situ synthesized poly(acrylonitrile‐butadiene‐styrene)/zinc oxide nanocomposites

“…The delay in PI can be due to the difficulty of mass transfer,19 as it was shown in Figure 2, the reaction mixture solutions in the presence of nanoparticles showed higher viscosity (up to 400%) in the conversion range analyzed. This fact can be explained in terms of chain polymer‐nanoparticles interaction, as mentioned by Chae and Kim20 in the case of polyacrylonitrile solutions. In the case of the particles used in this work, both ZnO surface and aminosilane modifier possess polar groups (hydroxyl and amino) which can form hydrogen bonds with the SAN matrix and/or SAN grafts 21,22…”