Microwave-assisted synthesis of poly(aspartic acid)

摘要

The reactions of polyCaspartic acid) syntheses were carried out in the microwave reactor. The cyclic form obtained,i.e. polysuccinimide [PSI,formula(IV) in Scheme A] was then subjected to alkaline hydrolysis in the presence of NaOH to reach finally the linear form,sodium salt of polyCaspartic acid) (PAspNa) [formula (V) in Scheme A presents its anion]. D,L-aspartic acid being a monomer [formula (III)] was dispersed in propylene carbonate and polimerized without the catalyst at temp. 160-230 °C for 41 min. The polymer obtained was precipitated with non-solvent,filtered and washed first with the same non-solvent and then with distilled water,and dried at room temperature. The effects of weight ratio monomer:solvent and the type of non-solvent on the reaction yield and molecular weight and polydispersity of the product were investigated changing the parameters mentioned.