Polyvinyl Acetate PVA

The macromolecule of polyvinyl acetate (PVA) is based on a monomer where an acetate group replaces a hydrogen atom in the ethylene monomer. It is not used as a structural polymer because it is a relatively soft thermoplastic and hence it is only used for coatings and adhesives. 

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Polyvinyl acetate (PVA), acrylic and other polymer dispersions have been widely used as anti-dust treatments for concrete floors for many years. In general, the polymer dispersions have been similar to those used in the manufacture of emulsion paints, and until recently have tended to be based on dispersions of relatively large polymer particles (particle size 0.15-0.25 x 10 m). Dispersions are now becoming available which offer superior performance as floor sealers. The chemical and water resistance of the various polymer dispersions which have been used in the past vary considerably from the PVA types, which are rapidly softened and eventually washed out by water, to acrylic and SBR types which exhibit excellent resistance to a wide range of chemicals. Water-based sealers are gaining wider acceptance because of... 

A bond coat of a polymer latex (also called polymer emulsions or dispersions) such as styrene butadiene (SBR), polyvinyl acetate (PVA) acrylics or modified acrylics. These are applied to the prepared concrete as... 

Acetic acid is an important industrial chemical. The reaction of acetic acid with hydroxyl-containing compounds, especially alcohols, results in the formation of acetate esters. The largest use of acetic acid is in the production ofvinyl acetate (Figure 1.1). Vinyl acetate can be produced through the reaction of acetylene and acetic acid. It is also produced from ethylene and acetic acid. Vinyl acetate is polymerized into polyvinyl acetate (PVA), which is used in the production of fibers, films, adhesives, and latex paints. 

In spite of Baekeland s success, it was another two decades before the Age of Polymers can really be said to have been born. The 1920s and 1930s saw the invention and/or commercialization of a number of new polymeric products ("plastics") that most consumers now consider to he essential chemicals in their lives. These products include the urea formaldehyde plastics (1923), polyvinyl chloride (PVC 1926), polystyrene (1929), nylon (1930), polymethylmethacrylate (acrylics 1931), polyethylene (1933), the melamine plastics (1933), polyvinylidene chloride (Saran 1933), polyvinyl acetate (PVA 1937), and tetrafluoroethylene (Teflon 1938). 

Acetylcholineesterase Miniaturized multichannel transduc-tor with planar Au electrode which was first covered with a choline-selective liquid membrane made from 66% PVC-polyvinyl acetate (PVA), 33% 2-nitrophenyl octyl ether plasticizer and 1% ion-pair choline phosphotungstate. A second layer of 2% AChE in the PVA-polyethylene dispersion was spread on the top. The electrode was used as working electrode versus Ag/AgCl for potentiometric measurement of Ch and ACh in 0.1 M Tris buffer at 7.4. Optimum pH range for the sensor was 7-9. The calibration graph was linear from 0.02-10 mm ACh and detection limit was 5 pM. Response time was 3-5 min. Sensor was suitable for determination of ACh in biological fluids. [86]... 

Polyvinyl chloride (PVC) and polyvinyl acetate (PVA) are considered to be the first synthetic polymers created. Safe-handling cellulose acetate soon replaced explosive cellulose nitrate. Polyacrylonitrile and polyamides (Nylon) soon followed. American companies such as DuPont pioneered the development of plastics. England was responsible for the early development of polyester polymerization. 

Vinyl acetate, the structure of which is shown below, undergoes addition polymerization to form polyvinyl acetate (PVA), used in paints and adhesives ... 

Most vinyl acetate is converted into polyvinyl acetate (PVA) which is used in the manufacture of dispersions for paints and binders and as a raw material for paints. It is also copolymerized with vinyl chloride and ethylene and to a lesser extent with acrylic esters. A substantial proportion of vinyl acetate is converted into polyvinyl alcohol by saponification or transesterification of polyvinyl acetate. The main applications for polyvinyl alcohol are either as raw material for adhesives or for fibres. It is also employed in textile finishing and paper glueing, and as a dispersion agent (protective colloid). The world production capacity of PVA was 4.35 Mt/a in 2005, of which 2.1 Mt were converted into polyvinyl alcohol. 

Int. Technol. Corp. 1992. Exposure to Volatile Components of Polyvinyl. Acetate (PVA) Emulsion Paints During Application and Drying. Washington, DC Natl. Paint Coat. Assoc., Inc., Vinyl Acetate Toxicol. Group... 

So-called white glues are particularly important. The chemical basis is polyvinyl acetate (PVA), the bonded joints - or traditionally adhesive gluings - are characterized by very high adhesive strengths, which usually result in adherend fractions after destructive testing. In order to avoid possible tensions, it is recommended to let the bonded joint set under even pressure (clamp) for more than the indicated... 

More than half of all the benzoic acid produced in the United States is used in the manufacture of various polymeric products, primarily the family of plastics known as the polyvinyl acetates (PVAs). The PVAs, in turn, are used as adhesives, caulks, sealants, and coatings for paper, film, and plastic foil. About a quarter of all benzoic acid is converted to its sodium and potassium salts, sodium benzoate (C6HsC00Na) and potassium benzoate (C6H5C00K), for use as food preservatives. Sodium benzoate and potassium benzoate are now the most widely used food preservatives in the world. They are added to a host of products, such as soft drinks and fruit juices, jams and jellies, baked goods, and salad dressings. They are also added to a number of non-food products such as mouthwashes, toothpastes, cosmetic creams, and deodorants. 

Polyvinyl chloride (PVC), which belongs to the family of vinyl polymers, and its copolymers vjith vinylidene chloride (PVDC), polystyrene (PS) and its copolymers, polyvinyl acetate (PVA), polyvinyl alcohol (PVAL), ethylene copolymers with vinyl alcohol (CEVA) are also employed in anticorrosion films [3,18,20,22-24]. 

High density polyethylene (HDPE) Polycarbonate (PC) Polyvinyl chloride (PVC) Polystyrene (PS) Polyurethane (PUR) Polyurea + PUR Low density polyethylene ethyl + vinyl acetate (LDPE + EVA) Polyvinyl acetate (PVA) Acrylonitrile-styrene-butadiene (ABS) Acrylonitrile-styrene copolymer (AS) Styrene-butadiene-styrene (SBS) Polysiloxane Gelatin/arabic gum (G/AG)... 

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. 

Break-in tools used to gain access to premises may well carry traces of paint that have abraded from painted surfaces at the point of entry. Commonly encountered household paint types include polyvinyl acetate (PVA), acrylics, alkyd enamels, epoxies, and chlorinated rubbers. Py-GC can distinguish between these different classes (Figure 8.4). 

In this section, the preparation of electrically conductive polyvinyl acetate (PVA) nanofibres, using vapour phase chemical polymerisation of pyrrole onto the surface of the nanofibres, is investigated. PVA is highly biocompatible and nontoxic and was selected for this study because of its excellent chemical resistance and physical properties. 

Polyvinyl acetate (PVA) - not recommended in external applications or under wet service conditions. 

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