Segmented Polyether Polyurethane Ureas

The change of PU properties as a result of the plasticization process does not always correspond to the well-known views on the plasticization pattern, which were developed based on investigations of plasticized polymers having a uniform chemical stmcture of soft and hard phases (for example, PVC and esters of cellulose). In fact, the traditional views on plasticization of polymers are not suitable for explanation of maity effects observed by blending different plasticizers in polyurethane material. This behavior can be demonstrated on an example of segmented polyether-urethane-ureas. Their initial stmcture and properties (without plasticizers) are widely investigated. 

Block copolymers were developed rapidly in the 1960s when living anionic polymerization was first utilized to synthesize triblock thermoplastic elastomers or elastoplastics. At the same time, step or condensation polymerization to produce thermoplastic polyurethanes, urea-urethane spandex fibers, and later more specialized materials, such as the semicrystalline polyester-polyether copolymers were developed [10]. Imide block or segmented copolymers utilizing... 

It has been recognized that many of the unique properties of the polyether or ester based polyurethanes are due to their phase-separated structure the hard segment (urethane or urea) rich domains provide the "solid attributes, while the soft segment (polyether or ester) rich domains... 

---