Orientational distribution in stretched poly(methyl methacrylate) from 13C NMR spectroscopy

✍ Scribed by Andrzej S. Kulik; Hans Wolfgang Spiess

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 378 KB
• Volume: 195
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1994.021950525

✦ Synopsis

Abstract

The orientational distribution in drawn amorphous poly(methyl methacrylate) extended to the ratio λ = 3 was measured with one‐ and two‐dimensional carbon‐13 NMR spectroscopy. In the analysis, signals from the carboxyl carbons were used as a probe of the orientational distribution. The angular‐dependent line shapes were analyzed to determine the orientational distribution function and the order parameter 〈P~2~〉. The analysis yielded 〈P~2~〉 = 0,21. A two‐dimensional rotor‐synchronized magic angle spinning experiment was also used to measure the order parameter. The obtained value 〈P~2~〉 = 0,22 is in excellent agreement with the 1D result. The experimental results obtained for 〈P~2~〉 are compared to those proposed by the pseudo‐affine model. 〈P~2~〉 predicted by theory is reduced due to conformational disorder present in the glassy state.