Phthalic acid Plastics

Naphthalene, also known as tar camphor, and its alkyl derivatives, such as l-(2-propyl)naph-thalene (Figure 13.10), are important industrial chemicals. Used to make mothballs, naphthalene is a volatile white crystalline solid with a characteristic odor. Coal tar and petroleum are the major sources of naphthalene. Numerous industrial chemical derivatives are manufactured from it. The most important of these is phthalic anhydride (Figure 13.10), used to make phthalic acid plasticizers, which are discussed in Chapter 14. 

Sulfate ion was incorporated on alumina and/or silica-alumina or transition metal oxide (iron oxide or zinc oxide) the catalysts were used in the oligomerization of oct-l-ene. The results showed that these sulfated catalysts had a higher activity and selectivity in the olefin oligomerization process, while the conventional catalysts such as cobalt sulfate or magnesium sulfate supported on alumina or silica-alumina exhibited lower activity in the same process. The oligomers had a sufficiently low degree of branching and were useful as a material for, e.g. phthalic acid plasticizer. 

Reactions of the Methyl Groups. These reactions include oxidation, polycondensation, and ammoxidation. PX can be oxidized to both terephthahc acid and dimethyl terephthalate, which ate then condensed with ethylene glycol to form polyesters. Oxidation of OX yields phthaUc anhydride, which is used in the production of esters. These ate used as plasticizers for synthetic polymers. MX is oxidized to isophthaUc acid, which is also converted to esters and eventually used in plasticizers and resins (see Phthalic acids and otherbenzenepolycarboxylic acids). 

Isophthahc (y -phthahc) acid [121 -91 -5] (IPA) is selected to enhance thermal endurance as well as to produce stronger, more resiUent cross-linked plastics that demonstrate improved resistance to chemical attack. TerephthaUc (p-phthaUc) acid [100-21-0] (TA) provides somewhat similar properties as isophthahc acid but is only used in selective formulations due to the limited solubiUty of these polyester polymers in styrene [100-42-5] (see Phthalic acid AND OTHERBENZENEPOLYCARBOXYLIC ACIDS). 

Chemical Designations - Synonyms Butyl Phthalate DBF Phthalic Acid, Dibutyl Ester RC Plasticizer DBF Witcizer 300 Chemical Formula 0-CjH4[C00(CH2)3CH3]2. 

Chemical Designations - Synonyms Phthalic Acid, Bis(8-methylonyl)esler Phthalic Acid, Diisodecyl Ester Plasticizer DDP Chemical Formula CjjH jO. ... 

The most common types of plasticizer are the phthalic acid esters of Cg, Cio alcohols citric acid esters and epoxy aliphatic esters. 

Di- and mono-esters of phthalic acid, an ortho-dicarboxylic acid derivative of benzene. These compounds are widely used as industrial plasticizers to coat polyvinylchloride surfaces of plastics used in food packaging and medical devices (iv drip bags, blood storage bags, etc.) and are common environmental contaminants. Several phthalate mono-esters are peroxisome proliferator chemicals and can activate the peroxisome proliferator-activated receptor PPAR. 

The flexibility of some plastics can be improved by the addition of small molecules called plasticizers. For example, pure PVC turns brittle and cracks too easily to make useful flexible plastic products. With an added plasticizer, however, PVC can be used to make seat covers for automobiles, raincoats, garden hoses, and other flexible plastic objects. Plasticizers must be liquids that mix readily with the pol Tner. In addition, they must have low volatility so that they do not escape rapidly from the plastic. Dioctylphthalate is a liquid plasticizer that is formed by condensing two alcohol molecules with one molecule of phthalic acid, as illustrated in Figure 13-10. 

Ejlertsson J, Svensson BH (1995) A review of the possible degradation of polyvinyl chloride (PVC) plastics and its components phthalic acids esters and vinyl chloride under anaerobic conditions prevailing in landfills. Dept, of Water and Environmental Studies, Linkoping University, Linkoping, p 20... 

The important influence that sample container materials can have on seawater sample composition is illustrated next by two examples one concerning the storage of metal solutions in glass and plastic bottles, the other concerning the storage of solutions of phthalic acid esters and polychlorinated biphenyls in glass and plastic. 

GeslerRM. 1973. Toxicology of di-2-ethylhexyl phthalate and other phthalic acid ester plasticizers. Environ Health Perspect 73-79. 

The phthalic acids are made by oxidation of the corresponding xylene isomer. They are used to make plasticizers and alkyd and polyester resins and fibers. Ortho-phthalic acid usually is not isolated because it loses a molecule of water so easily, forming phthalic anhydride, the commercially traded form of this strain of phthalic acid. 

It has been shown that polymers with free phthalic acid groups dissolve much faster and at a lower pH than those esterified with acrylic or methacrylic groups. The presence of plasticizer and the nature of the salts in the dissolution medium influence the dissolution rate [62],... 

Dissolution measurements under the microscope give several results which will be discussed separately. The first and most evident result is the penetration velocity of the solvent into the polymer. In order to judge the influence of the solvent s chemical constitution on the polymer we have chosen a number of phthalic acid esters which differ only in their ester groups and which are well known plasticizers. The polymer was a vinyl chloride-vinyl acetate (87 13) copolymer. The following plasticizers have been tested, (the abbreviations are indicated)... 

Kapton - [ENGINEERING PLASTICS] (Vol 9) - [HEAT-RESISTANT POLYMERS] (Vol 12) - [PHTHALIC ACID AND OTHERBENZENEPOLYCARBOXYLIC ACIDS] (Vol 18) - [POLYMIDES] (Vol 19) -as composite matrix [COMPOSITE MATERIALS - POLYMER-MATRIX - THERMOPLASTICS] (Vol 7) -ion implantation m [ION IMPLANTATION] (Vol 14)... 

Phthalic anhydride is used to make anthraquinone (Exercise 22-19) and to make esters of phthalic acid, which are used widely to plasticize polymers. 

The stability of org peroxides (such as acetyl benzoyl peroxide) is greatly increased by prepg a soln of the peroxide in at least 25% by wt of the esters of phthalic acid (such as di-Me or de-Et phthalate)] 14)H-A. Aaronson, "Desensitization of High Explosives by Waxes, Semi-Plastic RDX Compositions , PATR 1761 (1950) (A number of commercially... 

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