| Abstract
| - Poly[n-hexyl-(S)-3-methylpentylsilane] aggregates confined in microcapsules to keep the aggregation number andranging in average polymer mass mp in a microcapsule from 2 × 10-16 to 2 × 10-14 g were studied by circular dichroismmeasurements in ethanol (a nonsolvent) and tetrahydrofuran (an associative solvent at low temperature) at varioustemperatures. The weight-average molecular weight Mw and the polydispersity index (the ratio of Mw to the number-average molecular weight) of the polysilane sample were 6.6 × 104 and 1.07, respectively, and the average numberof polymer molecules in each capsule was estimated to be 1.9 × 103 for mp = 2 × 10-16 g and 1.7 × 105 for mp =2 × 10-14 g. The size of each aggregate did not affect the optical activity because the circular dichroism thus obtainedwas proportional to mp under the same conditions in the investigated mp range; on the other hand, the peak heightof the circular dichroism in tetrahydrofuran had a significant hysteresis between 0 and 25 °C. Moreover, the circulardichroism appreciably reflected the prepared method, that is, the temperature and solvent; in other words, the aggregatesmemorized the initial conditions in their stacking structures.
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