ISSN:
0098-1273
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The 1H spin-echo and 13C spin-lattice relaxation times have been measured for solutions of polystyrene derivatives: ortho, meta, and para-halo (F, Cl, Br) and ortho, meta, para, and α-methyl. Results obtained from these two techniques permit comparison of the intramolecular mobility of these polymers with that of polystyrene. Poly(α-methylstyrene) does not differ from polystyrene except for a slight slowing of both segmental reorientation and internal phenyl-group motions and apparent hindrance of the methyl-group rotation. Segmental reorientation of poly(m-methylstyrene) is similar to that of polystyrene; rotation of the methyl group is free, while the internal phenyl-ring process is slower. Poly(p-methylstyrene) and poly(o-methylstyrene) also contain freely rotating methyl groups; the intramolecular mobility decreases from the para to the ortho position of the substituent. Finally, in poly(o-bromostyrene) and poly(o-chlorostyrene), the internal motion of the phenyl ring is completely overshadowed by the segemental reorientation, which is itself quite reduced.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1977.180151209
