Polycarbonate polyester monomers

Ttihaloacyl aromatics have been prepared by Friedel-Crafts acylation of aromatics with CX COCl (X = Cl, Br) in the presence of AlCl. They are used as monomers in the preparation of polycarbonates, polyesters, polyamides, polyketones, and polyurethanes (91). 

Polycarbonates, polyesters and polyamides having 8-hydroxyquinoline end groups are prepared by carrying out the polymerizations in the presence of monomers such as derivative (121) (76MI11103), which act as chain terminators. The polymers could be chain-extended... 

Most polymerisation reactions do not progress to completion, resulting in the residues of starting materials in the plastic. Approximately 1-3% of residual monomer is found in acrylics, PVC, polystyrene, polycarbonates, polyesters, polyurethanes and formaldehyde polymers immediately after production. Monomers with boiling points lower than ambient are likely to have evaporated before the final product is used, while those with higher boiling points, including styrene monomer and terephthalates used in saturated polyesters, off-gas slowly from the plastic formulation and can often be detected by odour. 

The production of many organic compounds requires the use of a variety of industrial processes and feedstock chemicals (Wise and Fahrenthold, 1981). This results in wastewater that contains a range of aromatics including benzene, toluene, ethylbenzene, chlorinated benzenes, and nitrobenzenes. It is also known that the production of most resins (acrylic, epoxy, alkyl, polypropylene, and phenolic polyester) requires the use of monomers, which again leads to discharge of benzene, toluene, and ethyl benzene. The same may be said about the production of polycarbonates, polyester, and styrene. 

Figure 6.2 Chemical structures of monomers used to make polycarbonate polyester.

As with polyesters, the amidation reaction of acid chlorides may be carried out in solution because of the enhanced reactivity of acid chlorides compared with carboxylic acids. A technique known as interfacial polymerization has been employed for the formation of polyamides and other step-growth polymers, including polyesters, polyurethanes, and polycarbonates. In this method the polymerization is carried out at the interface between two immiscible solutions, one of which contains one of the dissolved reactants, while the second monomer is dissolved in the other. Figure 5.7 shows a polyamide film forming at the interface between an aqueous solution of a diamine layered on a solution of a diacid chloride in an organic solvent. In this form interfacial polymerization is part of the standard repertoire of chemical demonstrations. It is sometimes called the nylon rope trick because of the filament of nylon produced by withdrawing the collapsed film. 

These compds may be modified by monocar-boxy lie acids or poly hydroxy alcohols. This definition includes the polycarbonates (qv), which are a well-defined segment of the general class of polyesters. Unsaturated polyesters, which are produced when any of the reactants contain non-aromatic unsaturation, can be cross-linked or copolymerized with an un-saturated copolymerizable monomer. The formulas and properties of the class polyester are as varied and extensive as the reactants themselves. For specific information on the various sub-classes and sub-sub classes, the following refs should be consulted 9, 10, II, 16a, 17,18,... 

Nearly all of the polymers produced by step-growth polymerization contain heteroatoms and/or aromatic rings in the backbone. One exception is polymers produced from acyclic diene metathesis (ADMET) polymerization.22 Hydrocarbon polymers with carbon-carbon double bonds are readily produced using ADMET polymerization techniques. Polyesters, polycarbonates, polyamides, and polyurethanes can be produced from aliphatic monomers with appropriate functional groups (Fig. 1.1). In these aliphatic polymers, the concentration of the linking groups (ester, carbonate, amide, or urethane) in the backbone greatly influences the physical properties. 

Economic and ecological aspects of chemical recycling are examined, and the application of such processes to the recovery of monomers and intermediates from PETP, polyamides, polyurethanes, polycarbonates, unsaturated polyesters, polyacetals, PMMA and PS is discussed. 17 refs. SNIA... 

Extraction or dissolution almost invariably will cause low-MW material in a polymer to be present to some extent in the solution to be chromatographed. Solvent peaks interfere especially in trace analysis solvent impurities also may interfere. For identification or determination of residual solvents in polymers it is mandatory to use solventless methods of analysis so as not to confuse solvents in which the sample is dissolved for analysis with residual solvents in the sample. Gas chromatographic methods for the analysis of some low-boiling substances in the manufacture of polyester polymers have been reviewed [129]. The contents of residual solvents (CH2C12, CgHsCI) and monomers (bisphenol A, dichlorodiphenyl sulfone) in commercial polycarbonates and polysulfones were determined. Also residual monomers in PVAc latices were analysed by GC methods [130]. GC was also... 

Bisphenols is a broad term that includes many chemicals with the common chemical structure of two phenolic rings joined together by a bridging carbon. Bisphenol A is a monomer widely used in the manufacture of epoxy and phenolic resins, polycarbonates, polyacrylates and corrosion-resistant unsaturated polyester-styrene resins. It can be found in a diverse range of products, including the interior coatings of food cans and filters, water containers, dental composites and sealants. [4]. BPA and BP-5 were selected for testing by the whole... 

There are numerous bifunctional monomers used in condensation polymerization. Some of the more popular signature groups that turn up frequently are shown in Figure 22-3. Important copolymers made by condensation include epoxies, nylon, polyesters, polycarbonate, and polyimides. As always, there are exceptions, and one is Nylon 6 made by a ring opening reaction of caprolactam. All of these will be covered in the next two chapters. 

Extension of DKR to polymer chemistry would readily result in chiral polyesters, polycarbonates, or polyamides from an optically inactive monomer mixture. Scheme 10 describes three variants of chemoenzymatic catalysis applied in polymer chemistry that recently appeared in the literature. Route A uses AA and BB monomers to prepare chiral polymers from racemic/diasteromeric diols. Route B converts an enantiomer mixture of AB monomers to homochiral polymers. Route C is the enzymatic ring-opening polymerization of co-methylated lactones to homochiral polyesters. Details will be given in Sect. 3.4.2. 

Polymers are large molecules (macromolecules) that consist of one or two small molecules (monomers) joined to each other in long, often highly branched, chains in a process called polymerization. Both natural and synthetic polymers exist. Some examples of natural polymers are starch, cellulose, chitin (the material of which shells are made), nucleic acids, and proteins. Synthetic polymers, the subject of this chapter, include polyethylene, polypropylene, polystyrene, polyesters, polycarbonates, and polyurethanes. In their raw, unprocessed form, synthetic polymers are sometimes referred to as resins. Polymers are formed in two general ways by addition or by condensation. 

If this complex is sufficiently stable, then no further reaction occurs, and the polycondensation is obviated. However, as mentioned above, by using controlled monomer design, a variety of functionalised polymers (typical by with Mn = 10 000—30 000 and Mw/Mn = 2.0) can be synthesised polyethers [15,48 50], poly(thioether)s [48], polyesters [51,52], polycarbonates [53], polyketones [54], polysiloxanes [55-58], poly(carbosiloxane)s [59], poly(carbosilane)s [60], poly(carbodichlorosilane)s [61] and polymers with a conjugated % system [62]. 

Condensation polymers result from formation of ester or amide linkages between difunctional molecules. Condensation polymerization usually proceeds by step-growth polymerization, in which any two monomer molecules may react to form a dimer, and dimers may condense to give tetramers, and so on. Each condensation is an individual step in the growth of the polymer, and there is no chain reaction. Many kinds of condensation polymers are known. We discuss the four most common types polyamides, polyesters, polycarbonates, and polyurethanes. 

Polymers are long-chain molecules composed of repeated smaller units called monomers. The term polymer spans an enormous spectrum of substances that find widespread use in virtually all aspects of modern society. Polymers range from high-volume commodity types (polyethylene, polystyrene, etc. ), to synthetic fibers (polyesters, polyamides, etc.), to engineering resins (polycarbonates, polyacetals, etc.), and beyond. 

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