Study of motional processes in polymer blends composed of isotactic polypropylene and ethylene–propylene–diene monomer rubber by broad‐line 1H‐NMR

The broad-line 1H-NMR study of the polymer blend composed of isotactic polypropylene and ethylene–propylene–diene monomer rubber was carried out. The NMR measurements were performed on the samples of the polymer blend and on the components of the blend in the temperature range covering the glass-transition regions of all studied polymers. Conclusions were drawn from the temperature dependencies of the second moment M2 and of the data obtained by the decomposition of the spectra into the components related to the motionally distinct regions of the partially crystalline polymer. The mass fractions of the amorphous, intermediate, and crystalline domains and the widths of the spectra related to the particular phases were computed from the spectra. A double glass transition was revealed for the polymer blend. Different mechanisms of the motional processes related to the glass transition were deduced from the data. The gradual increase of the number of the chains and the enhancement of the chain mobility within noncrystalline regions of the polymer blend are responsible for the motion related to the lower glass transition and only transformation of the hindered motion into free motion was found in the temperature region of the upper glass transition. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 247–252, 2004

[1]  Shiqiang Huang,et al.  Miscibility of blends of ethylene‐propylene‐diene terpolymer and polypropylene , 2002 .

[2]  B. Nysten,et al.  Characterization of the molecular structure of two highly isotactic polypropylenes , 2001 .

[3]  J. Kotek,et al.  Toughness profile in injection-molded polypropylene: The effect of the β-modification , 1998 .

[4]  Donald Da-Jen Huang,et al.  The application of fracture mechanics to materials selection , 1996 .

[5]  D. Olčák,et al.  NMR Study of β Relaxation in Modified and Blended Isotactic Polypropylene , 1996 .

[6]  F. Mirabella.  Phase separation and the kinetics of phase coarsening in commercial impact polypropylene copolymers , 1994 .

[7]  D. Olčák,et al.  Influence of drawing on molecular mobility in polypropylene fibres studied by nuclear magnetic resonance , 1984 .

[8]  Klaus Unterforsthuber,et al.  Mathematical separation procedure of broadline proton NMR spectra of crystalline polymers into components , 1979 .

[9]  K. Bergmann.  Study of the molecular motions of polyethylene by line‐shape analysis of broad‐line proton NMR spectra , 1978 .

[10]  K. Bergmann,et al.  NMR-Untersuchung des Relaxationsverhaltens von Polyäthylen , 1972 .

[11]  F. Noack,et al.  Kernmagnetische Relaxation in festem Polypropylen , 1970 .

[12]  A. Peterlin,et al.  Temperature dependence of NMR absorption spectra of polyethylene , 1960 .

[13]  W. Slichter,et al.  Molecular Motion in Polypropylene, Isotactic and Atactic , 1958 .