Microstructural Characterization of Polymers by Positron Lifetime Spectroscopy
Title | Microstructural Characterization of Polymers by Positron Lifetime Spectroscopy PDF eBook |
Author | Jag J. Singh |
Publisher | |
Pages | 6 |
Release | 1996 |
Genre | |
ISBN |
Microstructural Characterization of Semi-Interpenetrating Polymer Networks by Positron Lifetime Spectroscopy
Title | Microstructural Characterization of Semi-Interpenetrating Polymer Networks by Positron Lifetime Spectroscopy PDF eBook |
Author | National Aeronautics and Space Adm Nasa |
Publisher | Independently Published |
Pages | 38 |
Release | 2019 |
Genre | Science |
ISBN | 9781792859113 |
Thermoset and thermoplastic polyimides have complementary physical and mechanical properties. Whereas thermoset polyimides are brittle and generally easier to process, thermoplastic polyimides are tough but harder to process. A combination of these two types of polyimides may help produce polymers more suitable for aerospace applications. Semi-Interpenetrating Polymer Networks (S-IPN) of thermoset LaRC(TM)-RP46 and thermoplastic LaRC(TM)-IA polyimides were prepared in weight percent ratios ranging from 100:0 to 0:100. Positron lifetime measurements were made in these samples to correlate their free volume features with physical and mechanical properties. As expected, positronium atoms are not formed in these samples. The second lifetime component has been used to infer the positron trap dimensions. The 'free volume' goes through a minimum at a ratio of about 50:50, and this suggests that S-IPN samples are not merely solid solutions of the two polymers. These data and related structural properties of the S-IPN samples are discussed. Singh, Jag J. and Pater, Ruth H. and Eftekhari, Abe NASA-TP-3617, NAS 1.60:3617, L-17576 RTOP 505-63-50-01...
Microstructural Characterization of Semi-Interpenetrating Polymer Networks by Positron Lifetime Spectroscopy
Title | Microstructural Characterization of Semi-Interpenetrating Polymer Networks by Positron Lifetime Spectroscopy PDF eBook |
Author | Jag J. Singh |
Publisher | |
Pages | 24 |
Release | 1996 |
Genre | Polyimides |
ISBN |
Positron Lifetime Spectroscopy for Investigation of Thin Polymer Coatings
Title | Positron Lifetime Spectroscopy for Investigation of Thin Polymer Coatings PDF eBook |
Author | Jag J. Singh |
Publisher | |
Pages | 12 |
Release | 1993 |
Genre | Coatings |
ISBN |
Low-energy Positron Flux Generator for Microstructural Characterization of Thin Films
Title | Low-energy Positron Flux Generator for Microstructural Characterization of Thin Films PDF eBook |
Author | Jag J. Singh |
Publisher | |
Pages | 24 |
Release | 1991 |
Genre | Microstructure |
ISBN |
Characterization of Free-volume Properties in Polymers by Positron Annihilation Spectroscopy
Title | Characterization of Free-volume Properties in Polymers by Positron Annihilation Spectroscopy PDF eBook |
Author | Qin Deng |
Publisher | |
Pages | 320 |
Release | 1993 |
Genre | Polymers |
ISBN |
Analysis of Positron Lifetime Spectra in Polymers
Title | Analysis of Positron Lifetime Spectra in Polymers PDF eBook |
Author | Jag G. Singh |
Publisher | |
Pages | 68 |
Release | 1988 |
Genre | Least squares |
ISBN |