Polyvinyl alcohol, PVOH

The stabilizing of aqueous latexes succeeded by using emulsifiers (anionic, nonionic) and/or their mixture, steric stabilizators (polyvinyl alcohol (PVOH), hydroxyethyl cellulose, polyethylene glycol, new protective colloids etc.), and polymerizable surfaces active agents, in general. Vinyl acetate (VAc) emulsion homopolymers and copolymers (latexes) are widely used as binders in water-based interior and exterior architectural paints, coatings, and adhesives, since they have higher mechanical and water resistance properties than the homopolymers of both monomers [2, 4, 7]. 

For evaluation of a resin as a creping adhesive, a 1% solids aqueous solution of the formulated resin is sprayed onto the siuface of a Yankee Dryer along with the appropriate amount of release agent to provide a good balance of adhesion and release. This application optimizes both the productivity of the paper machine and the quality of the product produced on the machine. The solid consists of about 50% polyvinyl alcohol (PVOH) and 10-50% (polyamide-epihalohydrin resin). A cellulosic fibrous web is pressed against the drying surface to adhere the web to the surface. The dry web is then dislodged from the... 

Microcapsules containing polymer and pigment were prepared in [299] by dispersing a viscous suspension of pigment and oil-soluble shell monomer forming o/w emulsions. Subsequently, a water-soluble shell monomer was added to the emulsion droplets, encapsulating them via interfacial polycondensation. These microcapsules were then heated for free radical polymerisation of the core monomers. It has been shown that polyvinyl alcohol (PVOH) used as stabiliser reacts with the oil-soluble shell monomers. The decrease of PVOH concentration as result of this interaction leads to coalescence of the particles and to the increase of their equilibrium particle size, however, methods are proposed to prevent the depletion of PVOH. 

Polyvinyl Alcohol (PVOH) and Ethylene Vinyl Alcohol (EVOH)... 

PVAL polyvinyl alcohol (PVOH) R D research and development... 

General Description A white-to-cream granular powder, DuPont Elvanol polyvinyl alcohol (PVOH) is a water-soluble synthetic polymer with excellent film-forming, emulsifying, and adhesive properties. This versatile polymer offers a high oxygen bar-... 

Polyvinyl Alcohol Polyvinyl Alcohol (PVOH) is awater-soluble synthetic polymer made by alcoholysis of polyvinyl acetate (PVA) and is available hydrolyzed, or partially hydrolyzed, and as a copolymer. 

A grass roots facility to produce polyvinyl alcohol (PVOH) is being constructed in a chemical complex on the U S. Gulf Coast. Your design team will complete the process engineering for the unit which produces polyvinyl acetate (PVAC). PVAC is further reacted in another part of the facility to produce the PVOH final product. The polyvinyl acetate unit includes the polymerization reactor system and the downstream recovery process. Your design must be capable of an annual production rate of 100 MMlb of PVAC intermediate. 

Formulations based on thermoplastic starch, EAA and polyethylene (PE) in different ratio, are suitable for film production. In Table 2.1 a few examples of such compositions (some of them containing also polyvinyl alcohol, PVOH) with their related tensile strength properties are reported. As can be seen, the film obtained with a gelatinized starch level of about 50% shows good tensile properties. 

Such products are normally based on cellulosic fibres such as viscose rayon 4iich are wetlaid using a water soluble binder, such as polyvinyl alcohol (PVOH), or can also be wetlaid using high-pressure, water jets (hydroentimglement). 

The main component of warp size is usually starch, polyvinyl alcohol (PVOH) or a blend of the two. Other size materials are sometimes used commercially to a lesser extent. These other, less often used types, include derivatized natural sizes and synthetic sizes listed in Table 7.12. In addition to the main size components... 

One of the first manufacturers of polyvinyl alcohol (PVOH) was Air Products Chemicals, which manufactured it under the Airvol trade name. It appears that the product may no longer be available, however. Another early manufacturer was ChrisCraft Industrial products, Inc., which still makes PVOH through its Monosol division. Another major supplier is Kuraray, which makes a variety of water soluble plastics, including PVOH under the name Poval. DuPont sells PVOH under the Elvanol tradename and Polyval under the name Enpol. There are other supphers as well. 

The complex formed by amylose with the complexing agent is usually crystalline, characterized by an amylose single helix around the complexing pol3mer [32]. Amylopectin does not interact with the complexing polymer, remaining in the amorphous phase. Starch can also be blended with polyvinyl alcohol (PVOH), for the production of foamed products, such as trays for food. Starch esters reinforced with natural fibers exhibit properties similar to those of polystyrene (PS). 

The initial popularity of tablets led to the logical question as to whether liquid detergents could be made available in a unit dose form. The resolution came with the development of a polymer pouch using polyvinyl alcohol (PVOH) as the container (Figure 19.4). 

Other polymers for which DSC-based studies of crystallinity have been reported include PET [1, 3], ethylene-propylene copolymers [4], PE gels [5], polyazomettine esters [6], polyvinyl alcohol (PVOH) microfibrils [7], polylactides [8], polycyclohexadiene [9], PET-polycarbonate (PC) copolymer [10], PE-like polyesters [11], cyclohexylene dimethylene terephthalate-PET copolymers [12], poly(trimethylene) 2,6-naphthalate [13], and isotactic polypropylene (iPP) [14]. 

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