Polymers containing carbodiimide groups

The use of dicarbodiimides as monomers in polyaddition reactions have not as yet found wide utility. However, polymers containing carbodiimide groups are known, and further nucleophilic reactions of these polymers with numerous substrates are reported. Carbodiimides, generated in situ from isocyanates are used as catalyst in the formation of polyamides from diisocyanates and dicarboxylic acids. Also, homoleptic lanthanide amidinates, made from carbodiimides, exhibit high catalytic activity for the ring opening polymerization of e-caprolactone at room temperature. ... 

Included in Table 2.10 are miscellaneous polymers containing reactive groups such as bromide [322, 323], chloride [340], isocyanate [261, 334, 337], carbodiimide [259],... 

The covalent coupling of a serine protease to a soluble-insoluble polymer (Eudragit) is also accomplished using a water soluble carbodiimide. Mycotoxins in foods often contain carboxyl groups suitable for carbodiimide mediated coupling with amino groups in proteins useful for developing immunoassay methods. " ... 

In the above-mentioned patents post-polymerization modification is performed in a single step. An alternative is the performance of two sequential modification steps. In the first step the polymer is reacted with tin or germanium derivatives (triphenyl tin, tributyl tin, diphenyl tin dichloride, dioctyl tin dichloride, phenyl tin trichlorde etc.). In the subsequent modification step heterocumulene compounds (ketenes, thioketenes, isocyanates, thioiso-cyanates and carbodiimides) are applied [437,438]. Specific interaction with silica is obtained by end group functionalization with vinyl monomers which contain hydroxyl or epoxy groups. The effects are observed if the PDI is below 5 [439,440]. 

Modification of the protein amine groups is the procedure most frequently used to produce antibody-liposome conjugates. Early procedures used crosslinking agents, such as l-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) (27,28) in the presence of preformed liposomes containing a lipophilic carboxylic acid. Condensing agents like these tend to form protein-protein polymers. Control of these reactions is typically difficult and complex, and as a result separation of the liposomes from protein polymers is a... 

---