Ethylene oxybenzoate

Polyesters [2] find use in fibers [poly(ethylene terephthalate), poly(ethylene oxybenzoate), poly(ester ethers), poly(ester amides), etc.] [1], coatings (especially unsaturated polyesters) [4], plasticizers, adhesives, polyurethane base resins, films, etc. Cross-linked polyesters prepared from glycerol and phthalic anhydride (alkyd resins) have been reviewed [20], High-melting poly aryl esters have been investigated for high-temperature applications. 

Table II. Internal Rotation Angles of Poly(ethylene Oxybenzoate) cx-Form on the Process of Analysis (U)...

In 1973, the Federal Trade Commission modified the generic definition of polyester to include in the polyester category materials that previously were polyester ethers or benzoate polyesters. As a result, the fiber known as poly (ethylene oxybenzoate) or PEB and manufactured under the trade name A-Tell in Japan came to be known as polyester. This material is made by reacting parahydroxy-benzoic acid and ethylene oxide to give... 

The ether group is common in some other a/f-copolymers. Many of these compounds have practical applications. For example, poly(ethylene oxybenzoate) is used as a filament yarn in the silk clothing industry. Other polymers are used as epoxy resins. Several examples of such ether-a/f-different groups are given in Table 9.3.3. Pyrolysis of these macromolecules generates compounds indicative of their composition. 

C14H12 = 3,3 -dimethyl-4,4 -biphenyldiyl j) Mol- % ratio ethylene terephthalate to oxybenzoate... 

Fig. 16a and b. Phase diagrams of poly(ethylene terephthalate-co-oxybenzoate). a. Crystal melting temperatures b. Glass transition temperatures. All samples with two glass transitions are most likely two-phase samples. The black circles up to 63 mol- % represent one-phase samples. Filled triangles W. J. Jackson, Jr. and H. F. Kuhfuss, J. Polymer Sci., Polymer Chem. Ed. 14, 2043 (1976). Open triangles R. W. Lenz and K. A. Feichtinger, Polymer Preprints, Am. Chem. Soc. Div. Polymer Chem. 20, 114 (1979). Filled circles Ref. 20). Open circle J. Menczel and B. Wunderlich, J. Polymer Sci, Polymer Phys. Ed., 18, 1433 (1980)... 

Hashimoto et al. [132] studied the fluorescence of the MCLC polyesters, poly[(ethylene terephthalate)-co-(p-oxybenzoate)], 66, and poly[(ethylene 2,6-naphthalene dicarboxylate)-co-(/ -oxybenzoate)], 67. The fluorescence of 66, both at relatively high concentration (5 x 10 3 mol dm-3) in hexafluoro-2-propanol,... 

Materials and Processing. Copolyesters of poly(ethylene terephtha-late) (PET) and para-oxybenzoic acid (FOB) were supplied by the Tennessee Eastman Corporation. Past work Indicates the copolyesters form thermotropic liquid crystalline phases at compositions containing more than 30 mole% POB (26,27,28). The composition of the copolyester studied here contains 60 mole% POB. Quiescent liquid crystalline films were made by compression molding the copolyester at 210, 230, 255, and 285 C, and followed by a quench Into Ice water, ambient air, or cooled In the press with the power off. Film thicknesses ranged between 0.05-0.15 mm. Another sa(q>le of the 40/60 PET/POB copolyester was melted at 270 °C In a Mettler hot stage, manually sheared between glass slides, and then ambient air cooled. 

The diazotization of anthranilic acid, a classic route to benzyne, when carried out in the presence of vinyl acetate, vinyl ethers or 1,1-dichloroethylene gives the expected benzocyclobutenes in about 40% yield. Despite the rather moderate yields this method represents a convenient route to multigram quantities of the parent compounds, benzocyclobutenol and benzocyclobutenone. The latter is easily converted to benzocyclobutene-1,2-dione. The diazotization sequence applied to 2-amino-3,6-dimeth-oxybenzoic acid and 1,1-dichloroethylene results in a 80% yield of 3, imethoxycyclobuten-l-one. Trapping of benzynes with other ethylene derivatives, and especially more substituted alkenes, has given generally poorer, variable results. ... 

Copolyesters of poly(ethylene terephthalate) and 4-acetoxybenzoic acid (PET / oxybenzoate) were synthesized by Jackson et al. through high temperature melt transesterification. However intricate details pertaining to the polyesterification kinetics have remained unexamined. In this system, insertion of 4-oxybenzoate moieties, with stiff rod like conformations, into flexible PET chains fosters the development of thermotropic character within a definite range of copolyester composition. 

Meesiti W, Menczd J, Gaur U, Wunderlich B (1982) Phase transitions in mesophase macromolecules. IIL The transitions in poly(ethylene terephthalate-co-p-oxybenzoate). J. Polymer Sd., Polymer Phys. Ed. 20 719... 

Fig. 7. Binary phase diagram for mixtures of hydrogen-bonding components of 4-but-oxybenzoic acid (2, n = 4) and trans-l,2-bis(4-pyridyl)ethylene 9...

EI-MS was used to analyze an aromatic copolyester with units of p-oxybenzoate (PO) and of ethylene terephthalate (ET). The El mass spectra were recorded up to 480°C. At these temperatures, the chain cleavage is totally selective, since PO units are stable and ET units are not. Chain statistics was applied to the El mass spectra and a good agreement was foimd between the computed and the known composition. ... 

Shinn Ted-Hong, Lin Chen-Chong, Lin David, C. (1995). Studies on Co [Poly( Ethylene Terephthalate-p-oxybenzoate)] Thermotropic Copolyester Sequence Distribution Evaluated from TSC Measurements. Polym, 36(2), 283-289. 

The three-phase structures 12, 13, and 14 are of particular interest because of the even more severe violation of the phase rule. At constant pressure, in equilibrium, only one-phase areas should be stable. Drawn fibers of poly(ethylene terephthalate) (PET) are discussed as three-phase sttucture with Figs. 5.68-72 and 5.113-115. As in polyethylene, the drawing to fibers or films orients the amorphous nanophase and achieves an arrested mesophase order, proven with Fig. 5.72. Since the drawing of PET fibers is much less efficient in extending the molecules than gel-spinning, there remains a sizeable portion of the amorphous phase, as shown in Fig. 5.71. The mobile mesophase of PET has not been found as a stable phase, as in polyethylene. Copolymers of PET with stiffer repeating units, such as oxybenzoate, however, have stable mesophases (see Chap. 7). 

In this section, copolymers of polyethylene are discussed, starting with low-density, branched polyethylene and culminating with crystallization, melting, and annealing of poly(ethylene-co-octene-l), also described as linear-low-density polyethylene, LLDPE. Furthermore, partial phase diagrams of poly(ethylene terephthalate-co-oxybenzoate), PETcoOB, andpoly(oxybenzoate-co-oxynaphthoate), POBcoON, are presented. The latter systems are examples of increasing chain stiffness by cocrystalUzation which leads to mesophase behavior (see Sect. 5.5). 

PETcoOB and POBcoON. A second example of thermal analysis of copolymers involves the two systems, poly(ethylene terephthalate-co-oxybenzoate), PETcoOB, and poly(oxybenzoate-co-oxynaphthoate), POBcoON. The structural formulas of the CRUs are as follows ... 

Of special importance is in this case that the backbone of the copolymer can change chemically by trans-esterification (see Fig. 3.47). In fact, heating poly(ethylene terephthalate) and acetoxybenzoic acid in the melt is a common synthetic route to PETcoOB. The inclusion of oxybenzoate groups makes poly(ethylene terephthalate) increasingly stiffer (see Fig. 1.50). In POBcoON, oxynaphthoate adds an additional off-set of the large zig-zag of the benzoate. As a result of this chain stiffening, the PETcoOB with more than 30 mol-% oxybenzoate shows an anisotropic melt, as for a nematic main-chain liquid crystal (see Fig. 5.136) and the system POBcoON has a mesophase character over the whole concentration range. 

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