ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
“Criss-cross”-cycloaddition of 4,4′-diisocyanatodiphenyl ether and 4-methoxybenzaldazine was used to synthesize α,ω-diisocyanato telechelics of molecular weights between 1 600 and 3 900. These precursors were reacted with different α,ω-dihydroxy functionalized aliphatic polyethers to produce segmented block copolymers in which the precursors obtained by cycloaddition reaction provide hard segment domains embedded in a polyether soft segment matrix. The resulting materials were soluble in common organic solvents such as tetrahydrofuran and chloroform and were characterized by spectroscopic techniques (1H-, 13C NMR, IR spectroscopy) as well as gel permeation chromatography (GPC) for molar mass determination. The block copolymers were molded in a hot stage press, and the resulting samples were characterized by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and stress-strain measurement. The materials with a hard segment fraction below 0.36 and a molecular weight above M̄n = 90 000 were elastomers with ultimate elongations above 700%.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1997.021980111
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