Poly imines

Poly(imines), Urea Thermosetting Resins, Poly (amides), and 

Poly(imines) are polymers that contain in their backbone amino nitrogens connected by single bonds to carbon atoms. Some of these polymers have a simple structure like poly(ethylene imine) or [-CH2-CH2-NH-]n. The polymer is obtained from the polymerization of aziridine, typically generating a mix of linear and branched macromolecules with about 25% primary amine groups, 50% secondary amine groups, and 25% tertiary amine groups. The polymer is used in paper industry and for various other purposes that make use of its anionic character [1]. 

The poly(imine) dendrimers form a special type of polymer. The dendrimers have different physical properties from linear polymers, and some have been used for biomedical applications. Dendrimers typically start with a core molecule. Ammonia can be used for this purpose. In the presence of methanol, ammonia reacts with methyl acrylate forming N(CH2CH2COOCH3)3. The resulting molecule can react further with ethylenediamine or other diamines forming N(CH2CH2CONHCH2CH2NH2)3- At the end of each branch is a free amino group that can react with two methyl acrylate monomers and further with two ethylenediamine molecules. The continuation of the process leads to a dendrimer (polyamidoamine or PAMAM) [2]. A different dendrimer is poly(propylene imine), which has butylenediamine as a core molecule. 

Another polymer with special properties from the class of polyimines is polyaniline, which can be obtained in a form with good electrical conductivity [3]. The idealized formula of polyaniline (for the nonionized form) is shown below  

The polymer is used in microwave absorbers and as conductive coating with good abrasion resistance for electronic components. Polyaniline is not thermoplastic and cannot be melted or even softened by heat. It is still stable up to about 240° C and starts decomposing at higher temperatures. 

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Vogtle et al. have prepared chiral poly(imine) dendrimers of various generations by condensation of non-racemic 5-formyl-4-hydroxy[2.2]paracyclophane moieties with poly(amine) dendrimers [71]. They have found that the optical activity of these dendrimers was nearly constant with increasing generation number. 

Figure 11 Proposed poly(imine) structure observed on platinum anodes during polymerisation...

Asymmetric hydrogenations catalyzed by supported transition metal complexes have included use of both chiral support materials (poly-imines, polysaccharides, and polyalcohols), and bonded chiral phosphines, although there have been only a few reports in this area. 

The Ir(III) trication is a 5d6 center and the electronic properties of its poly-imine complexes share several features with those of other well-known octahedral complexes of Fe(II) [14], Ru(II) [3], Os(II) [4], and Re(I) [5], whose metal centers are 3d6, 4d6, 5d6, and 5d6, respectively. Figure 3 depicts useful orbital and state energy diagrams for electronic transitions taking place in polyimine complexes of such d6 metal centers. 

Polypropylene imine) dendrimers (see Scheme 1 for structure) have been constructed step by step onto an amine functionalized polystyrene [38, 130, 131]. The challenge in this synthesis is finding conditions for the polypropylene imine) synthesis under which the low MW polystyrene (MW=3200) is soluble [38]. Similar poly(imine) dendrimers with carboxylic acid end groups have also been prepared [130]. The polypropylene imine) dendrimer has also been synthesized on an amino-terminated poly(2-methyl-2-oxazoline) [132]. 

Di(p-tolyl)-1,10-phenanthroline 14 is synthesized in 70% yield from 1,10-phenanthroline 3 (1 equiv) and 4-lithiotoluene 13 (5 equiv), after hydrolysis, oxidation with Mn02 and recrystallization (Scheme 9.11). This reaction, detailed in Protocol 9, follows a literature procedure to make various poly-imines substituted by alkyl or aryl groups a to the nitrogen atoms.20... 

Poly(imines), urea thermosetting resins, poly(amides), and poly(imides) 593... 

Block copolymers combing PBI with other types of macromolecular units have also been developed for superior membrane properties, as shown in Fig. 7.6. Two types of copolymers have been prepared, characterized, and evaluated as fuel cell electrolytes. One is the sulfcmated copolymer containing PBI and snUrmated polymer moieties for low temperature PEMs in both PEM fuel cells and direct methanol fuel cells (DMFCs) [123-126]. The other is the random copolymer containing PBI and poly(imine/ amide) moieties [127, 128]. For the sulfonated PBI copolymers, benzimidazole monomers... 

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