Accession Number:

ADA151515

Title:

Phase Separation in Polyurethanes - A Deuterium NMR Study.

Descriptive Note:

Technical rept.,

Corporate Author:

PRINCETON UNIV NJ DEPT OF CHEMICAL ENGINEERING

Personal Author(s):

• Dumais,J. J.
• Jelinski,L. W.
• Leung,L. M.
• Gancarz,I.
• Galambos,A.

Report Date:

1985-02-18

Pagination or Media Count:

20.0

Abstract:

Solid state deuterium NMR spectroscopy is used to address phase separation i specifically labeled polyurethanes. The hard segment is 4,4-diphenyl-methane diisocyanate MDI chain extended with 2,2,3,3,-D SUB 4 butanediol and the soft segment is polyoxypropylene end-capped with oxyethylene. The samples contain 100, 70, 60 and 50 wt hard segment. The results show 1 that the core of the hard segment microdomains is identical to the pure hard segment material with respect to molecular motion 2 that the amount of hard segment in the interfacial regions can be quantified 3 that the NMR and SAXS data are in good agreement concerning the fraction of interfacial hard segment and 4 that the interfacial hard segments undergo nearly isotropic motion on a 10,000,000s time scale, suggesting that there are few long-lived interrurethane hydrogen bonding interactions in the interfacial area. Author keywords include Polyurethanes Small Angle X-ray Scattering Microphase Separation Deuterium NMR.

Descriptors:

• *NUCLEAR MAGNETIC RESONANCE
• *SPECTROSCOPY
• *PHASE TRANSFORMATIONS
• *POLYURETHANE RESINS
• MICROSTRUCTURE
• HYDROGEN BONDS
• INTERFACES
• POLYPROPYLENE
• X RAY SCATTERING
• SEPARATION
• DEUTERIUM
• METHANE
• PHENYL RADICALS
• ISOCYANATES

Subject Categories:

• Plastics
• Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE