Use in Polymer Synthesis

In the polycondensation of aliphatic dicarboxylic acids with diols, DCC is used to mediate the reaction. In this manner biodegradable and surface active aliphatic polyesters are obtained. Also, hydroxycarboxylic acids derived from maleic or succinic acid are ho-mopolymerized in the presence of EDCCl in DMF at room temperature. In this manner 

The AB2 monomer, 3,5-bis-(3-hydroxypropyl-l-yl)benzoic acid is converted to a hyper-branched polyester using a carbodiimide to affect the polymerization. In this manner, soluble polyesters with molecular weights ranging from 500 to 11 000 and branching from 

22 to 0.33 are obtained. Using hexahydroxybenzene as the core highly branched den-drimers are prepared with 4-hydroxybiphenyl-4 -carboxylic acid, followed by reaction with 

3-PEO-5-PB substituted benzoic acid. All reactions are mediated by DIPCD.  

Carbodiimides are also used as catalysts in the formation of polyamides from dicarboxylic acids and diisocyanates. The carbodiimide catalyst is generated in situ from the diisocyanate using dimethylphospholene oxide as the catalyst. In this manner segmented thermoplastic poly(ether amides) and poly(ester amides) are obtained from the acid terminated monomers and diisocyanates by reaction polymerization processes. This reaction is best conducted in a vented extruder because carbon dioxide is the byproduct. 

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Simple conjugated dienes used in polymer synthesis include 1,3-butadiene, chloroprene (Z-chloro-l -butadiene), and isoprene (2-methyl-l,3-butadiene). Isoprene has been prepared industrially by several methods, including the acid-catalyzed double dehydration of S-methyl-l/S-butanediol. 

Diacetoxy-2-butene. Mitsubishi commercialized a new proces, the acetoxy-lation of 1,3-butadiene, as an alternative to the Reppe (acetylene-formaldehyde) process for the production of l,4-diacetoxy-2-butene. l,4-Diacetoxy-2-butene is tranformed to 1,4-butanediol used in polymer manufacture (polyesters, polyurethanes). Additionally, 1,4-butanediol is converted to tetrahydrofuran, which is an important solvent and also used in polymer synthesis. 

This volume closes with three chapters on different aspects of free radical chemistry in macromolecules. Several photoinitiation reactions that are widely used in polymer synthesis are discussed by Khudyakov and Turro in Chapter 12. This chapter also gives an informative description of how CIDEP can be used to simultaneously study... 

Other simple conjugated dienes used in polymer synthesis Lnclw. chloropreue 2-chloro-1.3-butactienre>and u)oprene(2-in thyM,3 huLa(li ni iMprene has been prepared industrially by several rndthods. including c> acid-catalyzed double dehydration of 3-methyM,3-buUnediol. 

Hydrophobic siloxane based liquid polymers have recently been used as inert reaction media in transition metal catalysed and yeast catalysed reactions. Reactive siloxane liquids have been used in polymer synthesis as the de facto solvent. There are probably many more reactions that could be performed in these liquid polymers, and isolation of water soluble products could easily be achieved in a separate aqueous phase. 

Introduction. Epichlorohydrin (1) is most widely used in polymer synthesis. Other common uses include an in situ trapping agent for HCl, HBr, or the alcohol generated during formation of Meerwein s reagent (eq 1). ... 

A recent addition to the realm of rosin derivatives used in polymer synthesis dealt with rosin-based acid anhydrides as curing agents for epoxy compositions [15] and showed that their performance was entirely comparable with that of petroleum-based counterparts, with the advantage of a simple process and, of course, their renewable character. 

Polyoxazolines have not yet been commercialized, but several derived polymers found various uses in polymer synthesis. Particularly, the conversion of these polymers into linear crystalline polyethyleneimine, unavailable otherwise, has interesting potentials. 

An aqueous Friedel-Crafts reaction has also been used in polymer synthesis. The acid-catalyzed polymerization of benzylic alcohol and fluoride functionality in monomeric and polymeric fluorenes was investigated in both organic and aqueous reaction media. Polymeric products are consistent with the generation of benzylic cations that participate in electrophilic aromatic substitution reactions. Similar reactions occurred in a water-insoluble Kraft pine lignin by treatment with aqueous acid. A Bisphenol A-type epoxy resin is readily emulsified in aqueous medium with an ethylene oxide adduct to a Friedel-Crafts reaction product of styrene and 4-(4-cumyl)phenol as emulsifier.Electrophilic substitution reaction of indoles with various aldehydes and ketones proceeded smoothly in water using the hexamethylenetetramine-bromine complex to afford the corresponding Z A(indolyl)methanes in excellent yields.InFs-catalyzed electrophilic substitution reactions of indoles with aldehydes and ketones are carried out in water.Enzymatic Friedel-Crafts-type electrophilic substitution reactions have been reported. ... 

Homogeneous hydrogenation is used in polymer synthesis, the hydrogenation of aldehydes to alcohols (oxo process), in asymmetric hydrogenation (L-dopa, Monsanto), and for the hydrogenation of benzene to cyclohexane (Procatalyse). 

F. Chen and S. Ying in Mechanics and Kinetics of Polymer Reactions and their Use in Polymer Synthesis International Symposium Honored Professor Pierre Sigwalt Occas, Paris, France, 1990. 

PD is currently produced commercially in small quantities by chemical synthesis using the toxic feedstock acrolein. Although 1,3-PD has not been produced on a large scale, there are dozens of potential uses in polymer synthesis and as a chemical intermediate (26), Cameron has also been involved in studies on strains of Clostridium thermosaccharolyticum that produce R(-)-1,2-propanediol, a useful chiral building block in organic synthesis (27),... 

Figure 12.4 Some common click reactions used in polymer synthesis and functionalization. (Adapted from Sumerlin and Vogt, 2010.)...

Most abbreviations are based on the form poly(monomer) , i.e. on the names of the monomers used in polymer synthesis, often with the prefix P for poly . In case of copolymers, the monomers are given in alphabetic order. Some abbreviations also catch structural features or physical properties. ... 

Diels-Alder reactions have been used in polymer synthesis as a method of producing highly crosslinked structures (Hay et ah, 1989 Stork et ah, 1999 Watson and Bass, 2000 Nenov et ah, 2002) and even as the polymerization mechanism itself (Bailey, 1972 Kamahori et ah, 1999). It has only been rather recently that it has been effectively utilized in the modular... 

Fig. 8.11 Nickel-catalyzed couplings, (a) Colon s initial experiments (b) the first use in polymer synthesis, (c) Max-dem s commercialized product Poly-X 25.

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