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Mechanical and swelling behaviour of well characterized polybutadiene networksEndlinking of hydroxyl-terminated polybutadiene with the appropriate isocyanate has been used to prepare well characterized networks. Two networks have been studied with molecular weights of the prepolymers being 6100 and 2400 g/mole by g.p.c. Cylindrical specimens were prepared and the derivatives of the stored energy function with respect to the stretch invariants were determined by torque and normal force measurements in torsion. From these data the Valanis-Landel (1967) stored energy function derivatives w-prime(lambda) were determined for both networks. The stored energy function for the junction constraint model of Flory (1953, 1977, 1979, 1985) which is a special form of the Valanis-Landel function, has been fitted to that determined from the experiments. The contributions to the stored energy function from the phantom network and from the junction constraints respectively do not agree with predictions from the topologies of the networks. In spite of this, the form of w-prime(lambda) for the junction constraint model gives an excellent 'curve fit' to the data. Comparison is also made with equilibrium swelling.
Document ID
19870053676
Document Type
Reprint (Version printed in journal)
Authors
Mckenna, Gregory B. (NBS, Polymers Div., Gaithersburg, MD, United States)
Hinkley, Jeffrey A. (NASA Langley Research Center Hampton, VA, United States)
Date Acquired
August 13, 2013
Publication Date
September 1, 1986
Publication Information
Publication: Polymer
Volume: 27
ISSN: 0032-3861
Subject Category
NONMETALLIC MATERIALS
Distribution Limits
Public
Copyright
Other