Synthesis And Properties Of Smart Shape Memory Polyurethane

The research of smart polymers has become the hottest field of materials. Many countries are researching and developing the novel functional materials. The shape memory polyurethane studied in this article is the most notable smart material because of excellent properties and broad using field.In this paper three series of polyurethane were synthesized and the properties were studied. Then the mathematic model of shape memory was established.Firstly, the monomer and condition of shape memory polyurethane synthesized were selected The liner polyester polyurethane was synthesized. The properties of calorifics, crystallinity, mechanism and shape memory were studied and the effect of structures on propt es were studied through the relationship between them. It was found that the high , ystallinity of the soft segment regions and the formation of hard segment domains are the necessary conditions for polyurethane with good shape memory behavior.Secondly, Shape memory polyurethane ionomer was synthesized. The properties of polyurethane ionomer were studied, including calorifics, dynamic mechanism and shape memory. Comparing to the liner shape memory polyurethane non-ionomer, ionomer has superior effect on shape memory behavior and water vapor permeability Especially the water vapor permeability increased from 5-8 times of liner SMP to 20-30 times of ionomersLastly the novel crosslinked shape memory polyurethane was synthesized, which shape recovering temperature were randomly controlled and can completely recover original shape. The properties of polyurethane were studied, including calorifics, dynamic mechanism and shape memory. Comparing to the liner shape memory polyurethane, The shape recovering temperature of the crosslinked polyurethane was randomly controlled and the crosslinked polyurethane has completely shape memory behavior. To explain the process of shape memory through mathematics, the mathematic model was established and tested...