Synthesis of polyureas with CO2 as carbonyl building block and their high performances

A series of polyureas were synthesized with CO2 as the carbonyl building block, which consist of a hard segment of CO2-based oligourea and a soft segment of soluble polyether diamine. The hard segment was formed from 1,3-bis(3-aminopropyl) tetramethyl disiloxane with CO2, and the soft segment was obtained through polyaddition of polyether diamine with an extender agent. The Number-average Molecular Weight (Mn) and Weight-average Molecular Weight (Mw) were estimated by Gel permeation chromatography (GPC). The properties of the synthesized polyureas such as thermo-stability and the tensile strength were examined, and these properties could be adjusted by varying the molecular weight of polyether diamine and oligourea segments. The synthesized polyureas have an amorphous structure and presented satisfied thermo-stability (similar to 250 degrees C) and the high tensile strength (22.4 MPa).