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Aspects of a gel technology for obtaining polyvinyl alcohol fi bers from the high-molecular-weight polymer are examined, and studies are made of the rheological and morphological characteristics of fi bers formed from solutions of different concentrations. It is shown that the use of a dry-wet forming method instead of the competing methods of thermotropic transformation and wet precipitation makes it possible to obtain fi bers having a strength of 2.2 GPa and an elastic modulus of up to 32 GPa.The successful development of gel technology for obtaining high-strength fi bers of ultrahigh-molecular-weight polyethylene (PE) [1] served as the impetus for research aimed at developing similar materials based on different fl exiblechain polymers, particularly polyvinyl alcohol (PVA). The trans-conformation of PVA chains in a crystal has an elastic modulus on the order of 250 GPa, which also makes it possible to obtain good mechanical characteristics for fi bers that are based on them [2]. The mechanical properties of these fi bers are in turn important for improving the service properties of various types of composite materials.Composites are presently being reinforced by using fi bers based on aliphatic and aromatic polyamides, carbon fi bers, and fi bers of high-molecular-weight PE. Each of these types of fi bers has its own advantages and disadvantages. High mechanical indices have yet to be obtained for fi bers made from aliphatic polyamides, while the production of fi bers based on aromatic polyamides is technologically complex. Aromatic-polyamide-based fi bers are expensive, as are carbon fi bers. In addition to the fact that high-strength PE fi bers are made by a complicated and environmentally unsafe technology, they are characterized by low adhesive strength, high creep rate, high fl ammability, and a limited range of service temperatures.The factors just mentioned and industry's strong need for different types of composite materials are serving as an impetus for the development and production of new types of fi bers for composites. Fibers obtained from high-molecularweight PVA (HMPVA) by gel technology are very promising in this regard. However, the production of HMPVA fi bers is complicated by the fact that the system must be cooled to below-zero temperatures in order to perform the thermotropic solution-gel conversion [3,4]. In this article, we report results of research focused on creating and examining the properties of HMPVA-based fi bers that are obtained by gel technology while avoiding the use of low temperatures and still preserving the advantages that gel technology offers for the production of high-strength fi bers. The wet-forming method [3] used for the production of low-molecular PVA is not well-suited for the production of high-molecular PVA because it does not make it possible to produce a stable gel. To solve the problem of obtaining high-strength HMPVA fi bers, we chose to analyze a drywet-forming method in which the precipitating bath is designed to fi x the shape of the fi lament by forming...

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