Blends with water-soluble polymers

Casein nanofibers electrospun Xie and Hsieh (2003) as blends with water-soluble polymers to obtain blend nanofiber and subsequently crosslinked with isocyanate. 

Blends of polyphenylenevinylene with water-soluble polymers have been prepared by mixing solutions of the sulfonium precursor with polyethyleneoxide, hydroxy-propylcellulose and polyvinylmethylether317). Polyethyleneoxide forms spherulites which impose a spherulitic texture to the polyphenylenevinylene that is retained after transformation. As a result of this open network, high conductivities are reached at only 10% conducting polymer. 

Spray Drying. Spray-dry encapsulation processes (Fig. 7) consist of spraying an intimate mixture of core and shell material into a heated chamber where rapid desolvation occurs to thereby produce microcapsules (24,25). The first step in such processes is to form a concentrated solution of the carrier or shell material in the solvent from which spray drying is to be done. Any water- or solvent-soluble film-forming shell material can, in principle, be used. Water-soluble polymers such as gum arable, modified starch, and hydrolyzed gelatin are used most often. Solutions of these shell materials at 50 wt % soHds have sufficiently low viscosities that they stiU can be atomized without difficulty. It is not unusual to blend gum arable and modified starch with maltodextrins, sucrose, or sorbitol. 

HPC is compatible with many natural and synthetic water-soluble polymers and gums (50). Generally, blends of HPC with another nonionic polymer such as HEC yield water solutions having viscosities in agreement with the calculated value. Blends of HPC and anionic CMC, however, produce solution viscosities greater than calculated. This synergistic effect may be reduced in the presence of dissolved salts or if the pH is below 3 or above 10. 

If specific interactions do occur between the components of a polymer blend, the mixing process will be exothermic (AWm negative) and miscibility can be realized. Water-soluble polymers are often miscible with each other, for example, because they participate in hydrogen bonding. 

An unusually stable foam that remains intact much longer than fire-fighting foams has been developed at Sandia National Laboratories. It results from a synergistic action caused when a water-soluble polymer and a fatty alcohol are blended with a solvent and a surfactant. A possible agricultural use would be in insecticide application. 

PVP is a nonionic water-soluble polymer that interacts with water-soluble dyes to form water-soluble complexes with less fabric substantivity than the free dye. Additionally, PVP inhibits soil redeposition and is particularly effective with synthetic fibers and synthetic cotton blends. The polymer comprises hydrophilic, dipolar imido groups in conjunction with hydrophobic, apolar methylene and methine groups. The combination of dipolar and amphiphilic character make PVP soluble in water and organic solvents such as alcohols and partially halogenated alkanes, and will complex a variety of polarizable and acidic compounds. PVP is particularly effective with blue dyes and not as effective with acid red dyes. 

Nishio, Y., Koide, T., Miyashita, Y., Kimura, N., Suzuki, H.J. Water-Soluble Polymer Blends with Partially Deacetylated Chitin A Miscibility Characterization. Appl. Polym. Sci. 37, 1533-1538 (1999)... 

The combination of starch with a water soluble polymer such as PVOH (or polyalkylene glycols) has been widely considered since 1970 [100]. Since the early 1990s these compositions have been mainly studied for starch-based loose-fill production as a substitute for expanded PS [101-107], using compositional water as expanding gas. In this kind of blends, not only natural starch but also modified ones such as hydroxy propylated high amylose starch can be used, especially to improve foam resilience and density [101-105]. 

J. A. Faucher and M. R. Rosen, Shaped Article for Conditioning Hair, a Blend of Water-Soluble and Water-Insoluble Polymers with Interpenetrating Networks, U.S. Pat. 4,018,729 (1977). Polymer blend, hair conditioning combs of (polycaprolactone blend, hair conditioning combs. Hair preparations, conditioners water insoluble/water soluble polymer blends and IPN-related materials. Combs and shaped articles. 

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