Study On The Intermolecular H-bond Interactions In Segmented Polyurethane-Ureas

Intermolecular interaction is one of the basic investigations in polymer physics. Hydrogen bonding is the most important interaction that has been the topic of research for many years. Segmented polyurethanes are one of the most widely investigated types of copolymers composed of alternating soft and hard segments. Typical polyurethanes are extensively H-bonded. Diamine extenders based polyurethane-ureas, where there are more than one H-bond donor (including two N-H in urethane-urea group and one N-H in urethane group) and more than one H-bond accepters (including two C=O in urethane group and urethane-urea, and C-O-C in soft segment), are much more complicated, as there are two N-H in urethane-urea group. There are fewer references, however, studying on PUU than that dealing with PU, possibly due to more complicated structure and H-bond properties. In the present paper, model compound, FTIR and molecular mechanics (MM) were used to study the intermolecular H-bond interactions in model soft segments, model hard segments and segmented PUU, respectively, in order to open out the rule of the H-bond interactions in PUU and its relationship with PUU chian structure. The effect of the phenyl ring on the H-bond interaction in PUU was also preliminarily studied. Besides, MM has been used, for the first time, to systematically investigate the H-bond of PUU, and has established the way of using MM to study the H-bond interactions in PUU.First, model soft segments, model hard segments and segmented model PUUs...