Poly vinyl butyral

Major polymer applications safety glass interlayer (automotive windshields), control of light, heat and sound in construction glass, bulletproof glass, adhesives and sealants, binders for rocket propellant, photoconductive papers, magnetic tapes, powder coating, wood sealers and primers, inks, ceramic binders, dry toners, wash primers, composite fiber binders 

Important processing methods compounding, powder coating, extrusion 

Typical fillers calcium carbonate, aluminum hydroxide, zinc oxide, rust protective fillers 

Fatty acid amides are well known as an important class of polymer additives used as a slip agent or lubricant to prevent unwanted adhesion. Unfortunately the addition of such amides for the purpose of antiblock additives for polymer sheets, in glass laminates (reduction of imwanted adhesion between surfaces of the polymer sheet itself) adversely affects the optical characteristics of the polymer sheet, such as haze, transparency, and film clarity, as well as adhesion of the polymer sheet to glass. Consequently, the inclusion of fatty acid amides polymer sheet interlayers in glass laminates is necessary. 

Cretekos and J.R. Wagner, Jr, Block-resistant film, US Patent 6 472 077, assigned to Exxon Mobil Oil Corporation (Fairfax, VA), October 29, 2002. 

Markarian, Slip and antiblock additives Surface medication for film and sheet. Plastics, Additives and Compounding, 9(6) 32-35, Novem-ber-December 2007. 

Donovan, and R, Balloni, Ffeat sealable film and method for its preparation, US Patent 4 692 379, assigned to Mobil Oil Corporation (New York, NY), September 8,1987. 

Chuayjuljit, C. Kunsawat, and P. Potiyaraj, Use of silica from rice husk ash as an antiblocking agent in low-density polyethylene film. Journal of Applied Polymer Science, 88(3), 2003. 

As a safety glass interleaver, poly(vinyI butyral) (Butacite, Saflex) is extensively used because of its high adhesion to glass, toughness, light stability, clarity and moisture insensitivity. 

It also finds miscellaneous applications in textile and metal coatings and in adhesive formulations. Where it is to be used as a safety glass interleaver, a very pure product is required and this is most conveniently prepared from 

In a typical process 140 parts of fully hydrolysed poly(vinyl alcohol) are suspended in 800 parts of ethanol 80 parts of butyraldehyde and 8 parts of sulphuric acid are added and the reaction is carried out at about 80 C for 5-6 hours. 

The solution of poly(vinyl butyral) is diluted with methanol and the polymer precipitated by the addition of water during vigorous agitation. The polymer is then stabilised, washed and dried. 

Laminated safety glass has now become standard for automobile windscreens and is used for aircraft glazing. 

The polymer contains both six membered full acetal groups separated by hydroxyl groups. PVB should not confused with poly (vinyl butyrate). PVB is commonly used as an hot melt adhesive for safety glasses. 

PVB is a natural polymer, produced in Burkholderia saccharin bacteria. Biofilms can be produced by casting processes. The films have been characterized by a variety of methods. The properties are highly influenced by the presence of a plasticizer, i.e., PEG. The thermal properties are comparable with domestic and industrial packing materials (19). 

For applications in ultrafiltration membranes, bioimaging, and diagnostics, a special method of synthesis of PVB has been suggested (20). There, swollen PVA particles are added to a butyraldehyde solution in ethanol. This methods gives polymers with high contents of butyral moieties up to 84%. 

A maximum of butyral groups are achieved using swollen PVA particles, 95 vol-% and pH 1. The reverse dissolution method has several advantages, such as (20)  

Acetal compoimds based on PVA are widely used. The biodegradation behavior of PVA modified by formaldehyde, n-butyralde-hyde, glyoxaldehyde and glutaraldehyde was investigated (21). It has been established that the biodegradation levels of all the acetal modified samples decreased. 

---

Styrene-acrylonitrile (SAN) copolymer Poly(vinyl butyrate) (PVB)... 

Poly(vinyl Butyral). Poly(vinyl butyral) is prepared according to the following reaction ... 

Poly(vinyl chloride) and poly(vinyl acetate) Poly(vinyl chloride), 15% glass-fiber-reinforced Chlorinated poly(vinyl chloride) Poly(vinyl butyral), flexible ... 

Cy—oxo-derived acids are the principal derivatives of the C —oxo aldehydes, and ia analogy to oxo aldehyde market appHcations, are used chiedy to make neopolyol esters, ie, those based on neopentyl glycol, trimethylolpropane, or pentaerythritol. These synlubes are employed almost entirely ia aeromotive appHcations. Heptanoic acid is also employed to make tetraethylene glycol diheptanoate, a plasticizer used with poly(vinyl butyral). 

Heat-reactive resins are more compatible than oil-soluble resins with other polar-coating resins, such as amino, epoxy, and poly(vinyl butyral). They are used in interior-can and dmm linings, metal primers, and pipe coatings. The coatings have excellent resistance to solvents, acids, and salts. They can be used over a wide range of temperatures, up to 370°C for short periods of dry heat, and continuously at 150°C. Strong alkaUes should be avoided. 

Heat resistance is an important characteristic of the bond. The strength of typical abrasive stmctures is tested at RT and at 300°C. Flexural strengths are between 24.1 and 34.4 MPa (3500—5000 psi). An unmodified phenoHc resin bond loses about one-third of its room temperature strength at 298°C. Novolak phenoHc resins are used almost exclusively because these offer heat resistance and because the moisture given off during the cure of resole resins results in undesirable porosity. Some novolaks modified with epoxy or poly(vinyl butyral) resin are used for softer grinding action. 

Analogously, poly(vinyl ketals) can be prepared from ketones, but since poly(vinyl ketals) are not commercially important, they are not discussed here. The acetalization reaction strongly favors formation of the 1,3-dioxane ring, which is a characteristic feature of this class of resins. The first of this family, poly(vinyl ben2al), was prepared in 1924 by the reaction of poly(vinyl alcohol) with ben2aldehyde in concentrated hydrochloric acid (2). Although many members of this class of resins have been made since then, only poly(vinyl formal) [9003-33-2] (PVF) and poly(vinyl butyral) [63148-65-2] (PVB) continue to be made in significant commercial quantities. 

Poly(vinyl alcohol) participates in chemical reactions in a manner similar to other secondary polyhydric alcohols (82—84). Of greatest commercial importance are reactions with aldehydes to form acetals, such as poly(vinyl butyral) and poly(vinyl formal). 

Poly(vinyl butyral), prepared by reacting poly(vinyl alcohol) with -butyraldehyde, finds wide appHcation as the interlayer in safety glass and as an adhesive for hydrophilic surfaces (161). Another example is the reaction of poly(vinyl alcohol) with formaldehyde to form poly(vinyl formal), used in the production of synthetic fibers and sponges (162). 

Reaction of poly(vinyl alcohol) [9002-89-5] with //-butyraldehyde yields poly(vinyl butyral) [63148-65-2] (PVB), a commercially important resia. 

The remaining (8%) //-butyraldehyde production of the United States goes into (in decreasing order) poly(vinyl butyral), 2-ethyIhexanal, trimethylolpropane, methyl amyl ketone, and butyric acid. 

Salts of neodecanoic acid have been used in the preparation of supported catalysts, such as silver neodecanoate for the preparation of ethylene oxide catalysts (119), and the nickel soap in the preparation of a hydrogenation catalyst (120). Metal neodecanoates, such as magnesium, lead, calcium, and zinc, are used to improve the adherence of plasticized poly(vinyl butyral) sheet to safety glass in car windshields (121). Platinum complexes using neodecanoic acid have been studied for antitumor activity (122). Neodecanoic acid and its esters are used in cosmetics as emoUients, emulsifiers, and solubilizers (77,123,124). Zinc or copper salts of neoacids are used as preservatives for wood (125). 

Oxidized castor oils are excellent nonmigrating, nonvolatile plasticizers (qv) for ceUulosic resins, poly(vinyl butyral), polyamides, shellac, and natural and synthetic mbber (see Rubber, natural). The high viscosity products are also used as tackifiers in gasket compounds and adhesives (qv) because of good oil and solvent resistance. They also serve as excellent pigment grinding media and as a base for inks (qv), lubricating oils, and hydrauHc oils (62). 

The wash primer is a special type of vinyl coating. This material contains a poly(vinyl butyral) resin, zinc chromate, and phosphoric acid in an alcohol-water solvent. The coating is so thin it is HteraUy washed onto a freshly blasted steel surface, where it passivates the metal surface by converting it to a thin iron phosphate-chromate coating. The alcohol solvent makes it possible to apply the coating over damp surfaces. The coating forms the first coat of... 

An industrial example of acidolysis is the reaction of poly(vinyl acetate) with butyric acid to form poly(vinyl butyrate). Often a butyric acid—methanol... 

Transesterification has a number of important commercial uses. Methyl esters of fatty acids are produced from fats and oils. Transesterification is also the basis of recycling technology to break up poly(ethylene terephthalate) [25038-59-9] to monomer for reuse (29) (see Recycling, plastics). Because vinyl alcohol does not exist, poly(vinyl alcohol) [9002-89-5] is produced commercially by base-cataly2ed alcoholysis of poly(vinyl acetate) [9003-20-7] (see Vinyl polymers). An industrial example of acidolysis is the reaction of poly(vinyl acetate) with butyric acid to form poly(vinyl butyrate) [24991-31-9]. 

Plasticizers. Plasticizers are materials that soften and flexibilize inherently rigid, and even britde polymers. Organic esters are widely used as plasticizers in polymers (97,98). These esters include the benzoats, phthalates, terephthalates, and trimeUitates, and aUphatic dibasic acid esters. Eor example, triethylene glycol bis(2-ethylbutyrate) [95-08-9] is a plasticizer for poly(vinyl butyral) [63148-65-2] which is used in laminated safety glass (see Vinyl POLYMERS, poly(vinyl acetals)). Di(2-ethyUiexyl)phthalate [117-81-7] (DOP) is a preeminent plasticizer. Variation of acid and/or alcohol component(s) modifies the efficacy of the resultant ester as a plasticizer. In phthalate plasticizers, molecular sizes of the alcohol moiety can be varied from methyl to tridecyl to control permanence, compatibiUty, and efficiency branched (eg, 2-ethylhexyl, isodecyl) for rapid absorption and fusion linear (C6—Cll) for low temperature flexibiUty and low volatility and aromatic (benzyl) for solvating. Terephthalates are recognized for their migration resistance, and trimeUitates for their low volatility in plasticizer appHcations. 

The products are amorphous resins whose rigidity and softening point depend on the aldehyde used. Poly(vinyl butyral), with the larger side chain, is softer than poly(vinyl formal). Since the reaction between the aldehyde and the hydroxyl groups occurs at random, some hydroxyl groups become isolated and are incapable of reaction. A poly(vinyl acetal) molecule will thus contain ... 

---