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Terephthalic acid, 762 table

The oxidation of p-xylene to terephthalic acid (Table 4, entry 33) would only result in the formation of p-toluic acid. To convert the second group in high yield and selectivity, the oxidation must be influenced in one of three ways ... [Pg.23]

Table 13. Physical Constants of Terephthalic Acid and Dimethyl Terephthalate... Table 13. Physical Constants of Terephthalic Acid and Dimethyl Terephthalate...
Table 18. World Capacities for Terephthalic Acid/Dimethyl Terephthalate, 10 t... Table 18. World Capacities for Terephthalic Acid/Dimethyl Terephthalate, 10 t...
Table 20. Specifications for Polymer-Grade Terephthalic Acid... Table 20. Specifications for Polymer-Grade Terephthalic Acid...
Table 23. Properties of terephthalic acid ester and Terephthaloyl Chloride... Table 23. Properties of terephthalic acid ester and Terephthaloyl Chloride...
You will recognize the side-chain oxidation of p-xylene to terephthalic acid as a reaction type discussed previously (Section 11.13). Examples of other reactions encountered earlier that can be applied to the synthesis of carboxylic acids are collected in Table 19.4. [Pg.806]

Polk et al. reported27 that PET fibers could be hydrolyzed with 5% aqueous sodium hydroxide at 80°C in the presence of trioctylmethylammonium bromide in 60 min to obtain terephthalic acid in 93% yield. The results of catalytic depolymerization of PET without agitation are listed in Table 10.1. The results of catalytic depolymerization of PET with agitation are listed in Table 10.2. As expected, agitation shortened the time required for 100% conversion. Results (Table 10.1) for the quaternary salts with a halide counterion were promising. Phenyltrimethylammonium chloride (PTMAC) was chosen to ascertain whether steric effects would hinder catalytic activity. Bulky alkyl groups of the quaternary ammonium compounds were expected to hinder close approach of the catalyst to the somewhat hidden carbonyl groups of the fiber structure. The results indicate that steric hindrance is not a problem for PET hydrolysis under this set of conditions since the depolymerization results were substantially lower for PTMAC than for die more sterically hindered quaternary salts. [Pg.547]

The important question of comparative value, mentioned earlier in Section 6, now must be considered. The material output of each process per unit of feed is estimated and multiplied by the market price of the material to arrive at a value of product. The output of the methanolysis processes, DMT and EG, are shown as a methanolysis-type product value in Table 16.5. The stoichiometric ratios are adjusted with a presumed 99 % recovery of DMT and 93 % recovery of EG. The output of the hydrolysis processes, TPA and EG, have the stoichiometric ratios adjusted for a presumed 99 % recovery of TPA and 93 % recovery of EG. The glycolysis processes, including methanolysis/BHET hybrid, are valued at 99 % recovery of terephthalic acid, 95 % recovery of ethylene glycol, and a US 0.022/kg esterification credit for making BHET. The EG recovery is higher for glycolysis-type products because of less loss of useful moieties. The three... [Pg.582]

Table 9.2 summarizes the uses of acetic acid. Vinyl acetate is another top 50 chemical. Acetic anhydride is used to make cellulose acetate and at times has been in the top 50 chemicals itself. Cellulose acetate is a polymer used mainly as a fiber in clothing and cigarette filters. Ethyl acetate is a common organic solvent. Acetic acid is used as a solvent in the manufacture of terephthalic acid (TA) and dimethyl terephthalate (DMT), which are monomers for the synthesis of poly(ethylene terephthalate), the polyester of the textile industry. A minor household use of acetic acid is as a 3-5% aqueous solution, which is called vinegar. [Pg.152]

Polymerization of esters to produce polyesters is an important commercial process. Polyethylene terephthalate or PET is one of the most common plastics used in food containers (Table 15.4). This ester is formed by the reaction of ethylene glycol and terephthalic acid (Figure 15.17). PET and other polyesters consist of esters linked together. Notice that both terephthalic acid and ethylene glycol have two carboxyls and two hydroxyls, respectively. When a polyester such as PET is formed, a monomer con-... [Pg.214]

Table 6.1 Polycondensation of terephthalic acid, TPA, and 4,4 -diaminodiphenylmethane, MDA, in the presence of poly(4-vinylpyridine) in N-methylpyrrolidone-pyridine solvent. [Reprinted from N. Yamazaki and F. Higashi, Adv. Polym. Sci., 38,1 (1981)]... Table 6.1 Polycondensation of terephthalic acid, TPA, and 4,4 -diaminodiphenylmethane, MDA, in the presence of poly(4-vinylpyridine) in N-methylpyrrolidone-pyridine solvent. [Reprinted from N. Yamazaki and F. Higashi, Adv. Polym. Sci., 38,1 (1981)]...
Tautomeric substance, 475, 1147 Teflon, 5, 64, 1015 Terephthalic acid, 751, 760 Tertiary amines, 414, 559, 1073 table of, and derivatives of, 661 Tertiary aromatic amines, crystalline derivatives of, 650 reactions of, 649, 1073 Tetrabromophenolsulphonephthalein, 989, 990... [Pg.1186]

A number of high melting point semiaromatic nylons, introduced in the 1990s, have lower moisture absorption and increased stiffness and strength. Apart from nylon-6 /6,T (copolymer of 6 and 6,T), the exact structure of these is usually proprietary and they are identified by trade names. Examples include Zytel HTN (Du Pont) Amodel, referred to as polyphthalamide or PPA (Amoco) and Aden (Mitsui Petrochemical). Properties for polyphthalamide are given in Table 2. A polyphthalamide has been defined by ASTM as "a polyamide in which the residues of terephthalic acid or isophthalic acid or a combination of the two comprise at least 60 molar percent of the dicarboxylic acid portion of the repeating structural units in the polymer chain" (18). [Pg.272]

Properties of PGT. Typical properties of PCT are shown in Tables 5 and 6 (154). Table 5 shows the standard grades and Table 6 the FR grades. This material is in effect a copolymer of terephthalic acid with two diols, the cis and trans forms of cydohexanedimethanol. These two isomers do not form a eutectic copolymer with a minimum melting point, but instead the melting point rises monotonically between the two Tm values of the pure... [Pg.299]

Results obtained for two mixed plastics are summarized in Table 4. A balance exists between process temperature, plastics feed rate, and product yields (67). For example, lower temperatures increase wax formation due to incomplete depolymerization. Slower feed rates and increased residence times reduce wax formation and increase the yield of liquids. The data summarized in Table 4 illustrate that the addition of PET to a HDPE PP PS mixture changes the performance of the Conrad process. Compared to the reference HDPE PP PS mixture, increased amounts of solids are formed. These are 95% terephthalic acid and 5% mono- and bis-hydroxyethyl esters. At higher temperatures, apparendy enough water remains to promote decarboxylation. [Pg.232]

As a dicarboxylic acid Gabler et al. used primarily terephthalic acid and in some cases isophthalic acid also. As diamine they used a number of branched aliphatic products, and the emphasis was on products having C-6 chain members separating the two NH2 groups. Table I lists some of Gabler s products. [Pg.630]

Table I. Amorphous Polyamides Based on Terephthalic Acid by Gabler et al. Table I. Amorphous Polyamides Based on Terephthalic Acid by Gabler et al.
Branched and Unbranched Diamines. To examine the influence of branching, polyamides based on adipic acid and terephthalic acid have been prepared with branched and unbranched diamines of equal chain length. Their melting points and glass temperatures are listed in Table II. [Pg.632]

Polyethylene Terephthalate. PET (Table 15.9) is produced by continuous melt condensation polymerization of ethylene glycol plus terephthalic acid,... [Pg.646]

In the second phase of the parametric study the removal of halogens from the reaction products was examined. Two different halogen removal methods were studied. The first method used a calcium oxide fixed bed placed between the reactor and condenser to remove organochloride vapours. However, it was found that the calcium oxide bed would plug up very rapidly if PET was present in the feed mixture and would become ineffective. This is because the PET would depolymerize into terephthalic acid and CO2 and would react with calcium oxide and cause it to plug up. The second method that was used for removal of chlorine was to add calcium oxide or hydroxide directly into the reactor with the plastic feed. It was found that this approach is far more effective than the previous method. Through trial and error it was found that calcium hydroxide feed of 10 wt% would remove the highest amount of chlorine (Table 19.7) [9]. [Pg.540]

In Table 26.8, the properties of the residue are also shown. It is notable that aluminum arising from laminated material and foil, and terephthalic acid from PET materials are dominant. The chlorine in the raw fluff transferred some 2.4% or so to the residue [3]. [Pg.675]

Table 4.2 Crystallographic cell constants for the two polymorphs of terephthalic acid... Table 4.2 Crystallographic cell constants for the two polymorphs of terephthalic acid...
Despite the usual preference in GC for the application of more polar stationary phases for the resolution of polar species, the former may be applied usefully for nonpolar separations. Figure 4 illustrates the resolution of the alkane-alkene pairs of the hydrocarbon fraction of shale oil (sample as in Figure 2), on a FFAP PLOT column (100ft). FFAP is Carbowax 20M terminated with terephthalic acid residues. This column selectively retains olefins and enables base-line resolution of the alkane-alkene pairs. The only disadvantage of this phase is its temperature limitation of ca. 250°C. Identification of the numbered peaks in Figure 4 was achieved by interfaced MS (components are listed in Table 1). [Pg.219]

In recent years, the relaxation and yield behavior of amorphous semi-aromatic polyamides has been the subject of a detailed analysis at the molecular level [1-6], Two series of materials were investigated, so-called SAPA-R and SAPA-A (Table 1). In the SAPA-R series, the chemical structure is based on isophthalic or terephthalic acid and 2-methyl 1,5-pentanediamine. In the SAPA-A series, the chemical formulae include isophthalic or terephthalic acid residues, diamino dimethylcyclohexylmethane residues, and lactam-12 sequences. [Pg.15]


See other pages where Terephthalic acid, 762 table is mentioned: [Pg.854]    [Pg.313]    [Pg.492]    [Pg.725]    [Pg.295]    [Pg.52]    [Pg.179]    [Pg.547]    [Pg.61]    [Pg.170]    [Pg.360]    [Pg.173]    [Pg.411]    [Pg.634]    [Pg.185]    [Pg.158]    [Pg.113]    [Pg.87]    [Pg.150]    [Pg.505]   


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