The rheological properties and aggregative stability of spinning solutions for obtaining aluminum-silicate fibrous materials are examined. It is shown that the acetate groups in polyvinyl alcohol affect the properties of the spinning solutions.The process of obtaining polycrystalline aluminum-silicate fibrous materials by solution technology includes obtaining homogeneous solutions which are subsequently transformed into a solid uniform xerogel [1,2]. The solutions must not contain any nonuniformity that softens the materials. In the process of concentration and transformation of the solutions into xerogel moisture is removed and the concentration of the main components increases; this can result in mutual destabilization of the solutions. In this connection, the spinning solutions (SS) must not lose aggregative stability and must not contain gel nonuniformities during preparation and concentration [3]. One of the main functions of polyvinyl alcohol (PVA) is to stabilize the spinning composition. In the present work the stabilizing power and surface activity of PVA and its capacity to form the required rheological properties of SS depending on the mass fraction of acetate groups present in them is examined.Samples of PVA with content of residual acetate groups from 7 to 18 wt.% and close values of the dynamic viscosity 4% of the solution (molecular mass) were used to investigate the effect of polyvinyl alcohol on the properties of SS.The samples obtained were used to prepare spinning solutions for aluminum-silicate fibrous materials. The compatibility of the components was observed visually. The aggregative stability of the spinning solutions was investigated with a KFK-3 photometer at wavelength 670 nm. The change in the optical density in time served as the criterion for the aggregative stability of the solutions. The rheological properties of the spinning solutions were determined with a MCR-501 rheometer in the rotation and oscillation regimes [4 -6]. The surface tension was determined by the method of ring detachment in a KRÜSS K-20 tensiometer at temperature 25 ± 0.5°C.The aggregative stability time of the samples of the PVA-based spinning solutions with acetate group content < 10 wt.% at 25°C is 11 days, and for acetate group content 15% the stability time of the solutions is at least 16 days (Fig. 1). An increase in the temperature of the SS results in sharp destabilization of the spinning composition (Fig. 2). At 40°C the stability time of the spinning solutions is 38 h (acetate group content 8 wt.%) and 72 h (acetate group content 15%). At 80°C SS with PVA and acetate group content < 10% forms a solid phase in the process of being concentrated, while SS with PVA and acetate group mass fraction from 10 to 15% remain stable for 48 h, which is adequate for concentrating the solutions and drying the materials. The increase in the aggregative stability time of solutions with the content of the acetate groups in PVA increasing from 10 to 15% is explained by a decrease in the fraction of OH-groups
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