RESUMO
PEG (Mn = 1000)-segmented polyurethanes, with hard segment percentage of 40%, 50% and 55% and named PU-H40, PU-H50 and PU-H55 respectively, were synthesized by bulk polymerization. The structure of PU was characterized by FTIR, DSC, and GPC. Mechanical properties, water contact angles and water vapor transmit rate(WVTR) were also tested. FTIR and DSC showed that the degree of microphase separation increased with the hard content. Mechanical test showed the tensile strength of PU-H50 to be 25 MPa, the highest tensile strength of the PU series. By the use of PEG as soft segment, the surface hydrophilicity of the materials increased dramatically. Owing to its high degree of microphase separation and the mobility of soft segment, the water contact angle of PU-H55 attained to 33 degrees. The WVTRs of PU-H40, PU-H50 and PU-H55 were 789 g/m2/24h, 705 g/m2/24h and 623g/m2/24h respectively. These data suggest that the materials are suitable for fabricating such biomedical articles as surgical gloves, wound dressing and medical protective coating.
Assuntos
Humanos , Materiais Biocompatíveis , Química , Polietilenoglicóis , Química , Poliuretanos , Química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de SuperfícieRESUMO
Adopting the two-step method and changing the proportion between PEG (Polyethylene glycol) and PTMG (poly (tetrahydrofuran), we used the MDI (4,4'-diphenylmethane diisocyanate) and short chain extender BDO (1,4-butanediol) as hard segment, the PTMG and PEG as soft segment, and hence prepared a series of polyether-based thermoplastic polyurethanes. FTIR showed the structure character of these polyurethanes. The determination of mechanics property and water contact angles revealed their good mechanics properties and hydrophilicity. Blood compatibility was evaluated by hemolysis test and platelet adhesion test, which revealed their good hemocompatibility. So those polyurethanes may be of wide application in the future.
Assuntos
Animais , Coelhos , Materiais Biocompatíveis , Química , Butileno Glicóis , Química , Isocianatos , Química , Teste de Materiais , Polietilenoglicóis , Química , Polímeros , Química , Poliuretanos , QuímicaRESUMO
Synthetic burn dressing remains the central theme for burn dressing development. The advantages and disadvantages of current available dressings were reviewed. As one of the most successful dressings, the hydrogel burn dressing, its combination with other materials and related progress in researches were presented in detail. Finally, the trend in development of synthetic burn dressing was presented.