Polymerization, interfacial polyamides production

Acid chlorides are very reactive and have as a condensation product hydrochloric acid.4,7 9 This hydrochloric acid can form an amine salt with unreacted amine groups, which should be avoided. To prevent this happening, acid binders, which are more reactive than the amines, are added. Polyamidation can be earned out using a solution and with an interfacial method. With the interfacial method one has the choice between a stirred and an unstirred process. In an unstirred process, the polymerization is at the interface and a rope can be drawn from the interface,... 

Synthesis of piperazine-terminated oligomers as prepolymers for interfacial membrane formation was also examined.46 48 Excess piperazine was reacted with di- and triacyl chlorides in an inert solvent such as 1,2-dichloroethane. The resulting amine-terminated polyamide oligomers had low solubility in the solvent system and precipitated. This served to limit the degree of polymerization of the oligomer. Even so, a portion of the product was insoluble in water and was filtered out during preparation of the aqueous oligomeric amine solution for the interfacial reaction step. 

Polyamides clearly dominate the field of thin-film composites by interfacial polymerization. The composition and morphology of the membranes depend on different parameters, including the concentration of the reactants, their partition coefficients and reactivities, the kinetics and diffusion rates of the reactants, the presence of by-products, competitive side-reactions, cross-linking reactions and postreaction treatment... 

Returning to our mysterious demonstration, the material could have been polyamide 610, synthesized via interfacial polymerization. Then elemental analysis would show the percent nitrogen, carbon, oxygen, and hydrogen, and each of the methods described above would be brought to play their roles. Ik however, it was concentrated hydrochloric acid and concentrated sodium hydroxide that were mixed, the result would eventually be shown to be sodium chloride, ordinary salt Philosophically, of course, conclusions are the product of reasoning power. It must be remembered that experiments provide evidence, and nothing else. 

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