Ether urethanes properties

Figure 5.1.1. Dependence for equilibrium swelling of crosslinked elastomer on the base of poly ether urethane. [Adapted, by permission, from V.Yu. Senichev in Synthesis and properties of cross-linked polymers and compositions on their basis. Russian Academy of Sciences Publishing, Sverdlovsk,1990, p.l6]...

These esters may be grafted to poly(ether-urethanes) either as homopolymers or copolymers by the procedure already outlined. In addition, they may be copolymerized directly with other vinyl monomers to give materials with a wide variety of properties. 

Basirjafari, S., R. Malekfar, and S. Esmaielzadeh Khadem. 2012. Low loading of carbon nanotubes to enhance acoustical properties of poly(ether)urethane foams. Journal of Applied Physics 112(10) 104312. 

Poly(ether urethanes) are of special interest due to their good mechanical properties, broad synthetic possibilities, and rather good blood compatibility for medical applications, e.g. catheters, heart valves [47]. A poly(carbonate urethane) (PCU) comprising poly(hexamethylene carbonate), the aromatic diisocyanate 4,4 -diphenylmethane diisocyanate (MDI) and 1,4-butanediol as chain prolonger has been developed (Table 2) [133]. 

Polyester soft segments impart better thermal and oxidative stability, oil and solvent resistance, higher abrasion resistance and strength to elastomers, expecially if they crystallize under stress, but they have lower hydrolytic, acid/base and fungus resistance than poly ether urethanes. Polyether urethanes have generally lower Tg and are better suited for low temperatures than the polyester urethanes. Polypropylene oxide-based soft segments are the least expensive, do not crystallize under any conditions and have excellent flexibility. PTMO-based polyurethanes have superior characteristics and an excellent balance of properties. 

Simultaneous and sequential IPNs based on various polymeric systems have been prepared using polydimethylsiloxane (PDMS) as the host network (3-8). These systems include poly(ether-urethane), polystyrene, poly(2,6-dimethyl-1,4-phenyleneoxide), polyacrylic acid, PDMS, polymethylmethacrylate, polyethylene oxide (PEO)... as the guest network. Some semi-interpenetrating networks (s-IPNs) based either on a linear polymer embedded in a polysiloxane network (5,9,10) or on a linear polysiloxane combined with a PEO network (8) have also been described. In some cases, PDMS has been replaced by polyaromatic siloxanes such as polydiphenyl or polymethylphenylsiloxanes (10-12). The focus of this paper concerns the preparation and properties of IPNs and s-IPNs based on polysiloxanes and poly(diethyleneglycol bis-allylcarbonate) (13,14). 

---