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Solid-State NMR Characterization of Cross-Linking in EPDM/PP Blends from 1H-13C Polarization Transfer Dynamics

Domenii publicaţii > Fizica + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: M. Aluas, C. Filip

Editorial: Solid State NMR, 27, p.165, 2005.

Rezumat:

A novel approach for solid-state NMR characterization of cross-linking in polymer blends from the analysis of 1H-13C polarization transfer dynamics is introduced. It extends the model of residual dipolar couplings under permanent cross-linking, typically used to describe 1H transverse relaxation techniques, by considering a more realistic distribution of the order parameter along a polymer chain in rubbers. Based on a systematic numerical analysis, the extended model was shown to accurately reproduce all the characteristic features of the cross-polarization curves measured on such materials. This is particularly important for investigating blends of great technological potential, like thermoplastic elastomers, where 13C high-resolution techniques, such as CP-MAS, are indispensable to selectively investigate structural and dynamical properties of the desired component. The validity of the new approach was demonstrated using the example of the CP build-up curves measured on a well resolved EPDM resonance line in a series of EPDM/PP blends.

Cuvinte cheie: Thermoplastic elastomers, Cross-linking, Solid-state NMR, CP-MAS, Polarization transfer dynamics

URL: http://www.sciencedirect.com/science?_ob=IssueURL&_tockey=%23TOC%235285%232005%23999729996%23561681%23FLA%23&_auth=y&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a047d75b863cd28521fb14f419822ad9