No abstract

No abstract

A polyion complex was formed from poly(acrylic acid) (PAA) and poly(4‐vinylpyridine) (PVP). Its structure and composition were examined by means of infrared spectroscopy (IR), x‐ray photoelectron spectroscopy (XPS), and elemental analysis. The polyion complex was obtained by dissolving PAA and PVP together in methanol. The composition of the polyion complex was independent of stirring speed, mixing sequence, and standing time after mixing. However, the composition depended on the concentrations and the ratio of the components in the reaction mixture. Excess of PAA in the product was observed when concentrated solutions (2.0 × 10−1M) were used for the preparation or when an excess of PAA was added to PVP. The sorption of water vapor by an equimolar PAA/PVP complex at 293 and 303 K was higher than that by the pure components, especially in the low‐ and middle‐pressure regions. In the high‐pressure region, however, the uptake was not affected by the complex formation. While hydrogen bond interactions in general decrease sorption, Coulombic interactions between polymer chains increased the sorption capacity.

Succinylation and reduction of wool fibers increase their water absorbability and enhance the re-use of waste wool fibers for functional materials. Water absorbability of these fibers improves with simple reduction and corresponds fairly well with the SH content of the reduced wool. When wool fibers are reduced and succinylated, water absorbability rises remarkably with increased add-on of succinic anhydride. In its most absorbent state, the reduced and succinylated wool holds 39 g · water/g · wool. The carboxyl groups introduced by succinylation into the fibers significantly contribute to the increased water absorbance of reduced and succinylated wool.

No abstract