Polystyrene-vinyl ketone copolymers

Blends. The type I reaction produces free radicals which, in the presence of oxygen, initiates photooxidation which also results in a decrease in the polymer molecular wei t. An indication of the relative importance of the type I reaction in these systems can be estimated from the amount of chain scission induced in a blend of the copolymers with homopolymer polystyrene. For these experiments, one part of 5% vinyl ketone copolymer was blended with four parts of styrene homopolymer to retain an overall ketone monomer concentration of 1%. 

Figure 6. Photolysis of 4 1 blends of polystyrene with polystyrene 5% vinyl ketone copolymers...

The alcohols, proprietary denatured ethyl alcohol and isopropyl alcohol, are commonly used for E-type inks. Many E-type inks benefit from the addition of small amounts of ethyl acetate, MEK, or normal propyl acetate to the solvent blends. Aromatic hydrocarbon solvents are used for M-type inks. Polystyrene resins are used to reduce the cost of top lacquers. T-type inks are also reduced with aromatic hydrocarbons. Acryflc resins are used to achieve specific properties for V-type inks. Vehicles containing vinyl chloride and vinyl acetate copolymer resins make up the vinyl ink category. Ketones are commonly used solvents for these inks. 

In this report we examine the effects of several vinyl ketone monomers on the photodegradation of polystyrene in the solid phase. Previous work Sj has indicated that copolymers containing vinyl ketones undergo photolysis by the Norrish type I and type n primary reactions. Studies by Golemba and Gulllet and by Kato and Yone-shiga 0 have shown that these processes also occur in copolymers of styrene with meUiyl vinyl ketone and widi phenyl vinyl ketone. 

Diacetone alcohol [123-42-2] (4-hydroxy-4-methyl-2-pentanone) is an almost odorless ketone alcohol that is weakly acidic as a result of rearrangement to the enol form. It is miscible with water and organic solvents except aliphatic hydrocarbons. It acts as a good solvent for cellulose esters and ethers, alcohol-soluble resins, castor oil, and plasticizers. Poly(vinyl acetate) and chlorinated rubber are partially dissolved or swollen. Polystyrene, poly(vinyl chloride), vinyl chloride copolymers, dam-ar resins, resin esters, rubber, bitumen, mineral oils, ketone resins, and maleate resins are insoluble. Diacetone alcohol is used as a high boiler in stoving enamels to improve flow and gloss. 

Isophorone [14.268], [14.269] is an unsaturated cyclic ketone. It consists of a-isophorone [78-59-1] (3,5,5-trimethyl-2-cyclohexen-l-one), which contains about 1-3% of the isomer P-isophorone [471-01-2] (3,5,5-trimethyl-3-cyclohexen-l-one). Isophorone is a stable, water-white liquid with a mild odor that is miscible in all proportions with organic solvents. It dissolves many natural and synthetic resins and polymers, such as poly(vinyl chloride) and vinyl chloride copolymers, poly(vinyI acetate), polyacrylates, polymethacrylates, polystyrene, chlorinated rubber, alkyd resins, saturated and unsaturated polyesters, epoxy resins, cellulose nitrate, cellulose ethers and esters, damar resin (dewaxed), kauri, waxes, fats, oils, phenol-, melamine-, and urea-formaldehyde resins, as well as plant protection agents. However, isophorone does not dissolve polyethylene, polypropylene, polyamides. 

Ethyl acetate [79-20-9] is a colorless, neutral liquid that is partially miscible with water and has a pleasant, fruity odor. It has a good solvency for cellulose nitrate, cellulose ethers, chlorinated rubber, poly(vinyl acetate), vinyl chloride copolymers, polyacrylates, polystyrene, fats, oils, and many natural and synthetic resins (alkyd resins, saturated polyesters, ketone resins). Cellulose acetate is, however, dissolved only in the presence of small amounts of ethanol. Poly(vinyl chloride) is insoluble. 

Isobutyl acetate [110-19-0] is a colorless, neutral liquid with a pleasant, fruity odor. It is miscible with organic solvents, but immiscible with water. Isobutyl acetate has a high solvency for cellulose nitrate, colophony, damar resin, ketone and ketone-formaldehyde resins, maleate resins, urea and melamine resins, and phenolic and alkyd resins. Polymers such as polystyrene, poly(vinyl ethers), poly(vinyl acetate), polyacrylates, chlorinated rubber and vinyl chloride copolymers, as well as fats, greases, and oils are readily dissolved. Postchlorinated poly(vinyl chloride) is less soluble. Polyisobutene, cellulose ethers, polymethacrylates, poly(vinyl butyrals), natural rubber, and manila copal are swollen. Shellac, cellulose acetate, cellulose acetobutyrate, poly(vinyl chloride), and poly(vinyl formal) are insoluble. 

N.N-Dimethylformamide [68-12-2] (DMF) [14.276] is miscible with water and organic solvents except aliphatic hydrocarbons. It is a good high-boiling solvent for cellulose esters, cellulose ethers, poly(vinyl chloride), vinyl chloride copolymers, poly(vinyl acetate), polyacrylonitrile, polystyrene, chlorinated rubber, polyacrylates, ketone resins, and phenolic resins. Alkyd resins and resin esters are partially soluble. Dimethylformamide does not dissolve polyethylene, polypropylene, urea-formaldehyde resins, rubber, and polyamides. It is used as a solvent in printing inks, for polyacrylonitrile spinning solutions [14.277], and as a solvent in the synthesis of acetylene. 

Cyclohexanone [108-94-1] (Hexanone) is insoluble in water, miscible with organic solvents. It is a high boiler with very good solvency for cellulose nitrate, cellulose ethers and esters, colophony, shellac, alkyd resins, natural and synthetic resins, chlorinated rubber, rubber, vinyl polymers and copolymers, polystyrene, ketone and ketone-formaldehyde resins, fats, oils, waxes, blown oils, and bitumen. [14.268],... 

Methyl Ethyl Ketone n (1876) (MEK, 2-butanone) CH3COC2H5. A low-boiling colorless, flammable solvent, possessing all the properties of acetone without its extremely high volatility. One of the most widely used solvents for several thermoplastics including cellulosics, acrylics, polystyrene, and vinyl copolymers. Bp, 80° C flp, 3°C (35°F) vp, 77 mmHg/20°C. Also known as MEK and Butanone. 

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