Polyesters chemical formula

Fig. 12.20 Random co-polyesters (a) Xydar series and (b) Vectra series. Uniike the usuai chemical formulae, the subscripts merely give the fractions of the various types of unit, which are distributed randomly along the polymer chain.

The following chemical formulas describe general stmcture of polyester plasticizers Acid terminated-polyester... 

Condensation (or step reaction) polymerization is the formation of polymers by stepwise intermolecular chemical reactions that may involve more than one monomer species. There is usually a low-molecular-weight by-product such as water that is eliminated (or condensed). No reactant species has the chemical formula of the repeat unit, and the intermolecular reaction occurs every time a repeat unit is formed. For example, consider the formation of the polyester poly(ethylene terephthalate) (PET) from the reaction between dimethyl terephthalate and ethylene glycol to form a linear... 

In 1929 Carothers proposed a generally useful differentiation between two broad classes of polymers condensation polymers in which the molecular formula of the structural unit (or units) lacks certain atoms present in the monomer from which it is formed, or to which it may be degraded by chemical means, and addition polymers, in which the molecular formula of the structural unit (or units) is identical with that of the monomer from which the polymer is derived. Condensation polymers may be formed from monomers bearing two or more reactive groups of such a character that they may condense intermolecu-larly with the elimination of a by-product, often water. The polyamides and polyesters referred to above afford prime examples of condensation polymers. The formation of a polyester from a suitable hydroxy acid takes place as follows ... 

TEREPHTHALIC ACID. CAS 100-21-01. Cf,H4(COOH)2, formula weight 166.13, crystalline solid sublimes upon heating, sp gr 1.510. The compound is almost insoluble in H2O, only slightly soluble in warm alcohol, and insoluble in ether. Terephtlialic acid (TPA) is a high-tonnage chemical, widely used in the production of synthetic materials, notably polyester fibers (poly-(ethylene terephthalate)). 

Terephthalic acid is an important chemical used in the manufacture of polyesters and plasticizers. It contains only C, H, and O. Combustion of 19.81 mg terephthalic acid produces 41.98 mg C02 and 6.45 mg H20. If 0.250 mol of terephthalic acid has a mass of 41.5 g, determine the molecular formula for terephthalic acid. 

This product was designed to give the textile trade the first trouble free soil-release in one bath. Thousands of yards of 65/35 polyester-cotton and 50/50 polyester-cotton have been processed with SUPERKLEEN as one of the key ingredients with excellent results. Naturally, it is very important that every chemical used in the finishing formula be of the quality that will not detract from soil-release properties. 

A 40-70 mol % of the compound of formula Ac- -CgH COOH are used to produce complex polyesters of high mechanical strength [45]. The polyesters with improved physic-chemical characteristics can be obtained... 

Eastman Chemical (UK) Ltd for the coil coating enamel formula in Table 13.3 and the polyester epoxy powder formulae in Table 14.4. Shell Chemicals for the can coating formula in Table 14.1 and the electrodeposition primer formula in Table 14.2. CIBA Polymers for the solventless epoxy formula in Table 14.3. Cargill Blagden for the one-pack polyurethane formulae in Tables 15.1 and 15.2. UCB sa for the UV-curing acrylic formula in Table 16.2. 

Source Kodak Technical Literature (ACCUMAX 2000) for polyester film Tables of Physical and Chemical Constants, Longman, London, 1973, p. 254 H. J. I ischbcck and K. H. Fischbeck, Formulas, Facts and Constants, Spiinger-Verlag, Berlin, 1987, for glass data. 

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