Premium
Mechanical properties of crosslinked polyurethanes
Author(s) -
Dzierża W.
Publication year - 1978
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.1978.070220514
Subject(s) - materials science , elastomer , stress relaxation , polyurethane , adipate , viscoelasticity , relaxation (psychology) , polymer chemistry , elastic modulus , composite material , creep , psychology , social psychology
Stress–strain and stress–relaxation behavior of polyurethane elastomers based on poly(ethylene adipate), poly(ethylene maleate), polyethylene glycol, and 4,4′‐diphenylmethane diisocyanate (MDI) have been studied. The elastomers were crosslinked by an excess of MDI and by dicumyl peroxide (DiCup); the latter was supposed to form additional crosslinks on the unsaturated bonds. The determined values of Young's modulus, Mooney‐Rivlin elastic parameters C 1 and C 2 , relaxation moduli E (10 sec) and E (100 sec), as well as relaxation speed were used to estimate the effect of MDI‐ and DiCup‐formed crosslinks on the mechanical behavior of polyurethanes. It was found that while the elastomers crosslinked by MDI only apparently displayed viscoelastic properties, the polyurethanes additionally crosslinked by DiCup exhibited more elastic behavior. The results obtained were explained on the basis of changes in the amount of secondary bonding due to the additional network junctions formed by DiCup at nonpolar groups.