Document Detail

Synthesis of HMDI-based segmented polyurethanes and their use in the manufacture of elastomeric composites for cardiovascular applications.
MedLine Citation:
PMID:  17550659     Owner:  NLM     Status:  MEDLINE    
For short-term cardiovascular application, segmented polyurethanes (SPUs) based on 4,4-methylenebis(cyclohexyl isocyanate) (HMDI), polytetramethylenglycol (PTMG) and 1,4-butanediol (BD) were synthesized and characterized by spectroscopy (FT-IR, (1)H-NMR) and thermal (TGA, DMA, DSC) and mechanical techniques. The segmented nature of the SPUs was not easily established by spectroscopic means; however, TGA allowed the quantification of the rigid segments content by the significant mass loss between 348 and 356 degrees C. The alpha transition was detected by DMA and related to the T(g) of the soft segments at -50 degrees C, while DSC showed the presence of an endothermic transition above 80 degrees C attributed to the melting of rigid segments. Two types of composites were prepared using the synthesized SPUs and Lycra (either T162B or T162C). The first one consisted of a two layers casting laminated while the second one was a classic unidirectional fibre-reinforced material. Laminate composites prepared with SPU containing 23.9% and 33.9% of rigid segments and Lycra T162C exhibited a higher tensile modulus but lower tensile strength than composites prepared with Tecoflex SG-80A (39.7% of rigid segments). The energy of adhesion between layers on these composites ranged from 475 to 2150 J. Fibre-reinforced SPUs exhibited higher moduli than the two layer laminated composites with increasing amounts of rigid segments in the matrix and by increasing Lycra T162C content (up to 10%). This behaviour was explained by SEM, which showed a good fibre-matrix bonding.
R E Solís-Correa; R Vargas-Coronado; M Aguilar-Vega; J V Cauich-Rodríguez; J San Román; A Marcos
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of biomaterials science. Polymer edition     Volume:  18     ISSN:  0920-5063     ISO Abbreviation:  J Biomater Sci Polym Ed     Publication Date:  2007  
Date Detail:
Created Date:  2007-06-06     Completed Date:  2007-09-05     Revised Date:  2008-02-20    
Medline Journal Info:
Nlm Unique ID:  9007393     Medline TA:  J Biomater Sci Polym Ed     Country:  Netherlands    
Other Details:
Languages:  eng     Pagination:  561-78     Citation Subset:  IM    
Unidad de Materiales, Centro de Investigación Científica de Yucatán, A.C. Calle 43 #130, Col. Chuburná de Hidalgo, 97200, Mérida, Yucatán, México.
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MeSH Terms
Biocompatible Materials / chemical synthesis*
Cardiovascular Diseases / therapy
Composite Resins
Cyanates / chemical synthesis*
Elastomers / chemical synthesis*
Materials Testing
Phase Transition
Polyurethanes / chemical synthesis*
Reg. No./Substance:
0/Biocompatible Materials; 0/Composite Resins; 0/Cyanates; 0/Elastomers; 0/Polyurethanes; 3173-53-3/cyclohexylisocyanate

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