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in feed strongly affected
the selectivity on the inclusion of amylose in this polymerization
manner. When the vine-twining polymerization was carried out
in higher concentrations of Glc-1-P and Glc
The concentrations of Glc-1-P and Glc
7
than those described
earlier, for example, 15 times, the unit ratio of POXT/PTHF in the
products was increased (0.21:1.00) upon increasing the yields of
the products (ca. 20 times). Because the concentration of PTHF
decreased with the progress of the polymerization due to the
predominant inclusion, amylose probably started to include POXT at
a later stage of the polymerization.
An attempt of the selective inclusion by amylose in the vine-
twining polymerization was also made in the system using the
resemblant polyesters (Fig. 8.1b) [2]. The selective inclusion of
amylose toward two resemblant polyesters was performed by the
vine-twining polymerization in the presence of a mixture of PVL
(
7
= 930) under the conditions same as those
toward polyethers described earlier. The
M
= 830) and PCL (
M
n
n
1
H NMR spectrum of the
employed mixture of the guest polyesters (CDCl
) showed that the
unit ratio of PVL/PCL in feed was assessed to be 1.00:0.92 (Fig.
8.3a). However, in the
3
1
H NMR spectrum of the product obtained by
the vine-twining polymerization (DMSO-
), the signals due to PVL
and amylose were observed, whereas no signals due to PCL appear
(Fig. 8.3b), indicating that amylose has selectively included PVL.
d
6
8.1.2
Amylose Selectively Includes a Specific Range of
Molecular Weights in Polymers
On the basis of the aforementioned findings, the selective inclusion to a
specific range of molecular weights (MWs) in synthetic polymers was
investigated by amylose in the vine-twining polymerization because
synthetic polymers generally have molecular weight distribution
(MWD), meaning that they are reasonably considered as mixtures
of analogous molecules with different numbers of the repeating
units. Additionally, the number of repeating unit (MW) contributes
to show different properties of the polymer with the same structure
of repeating unit. For example, PTHF with considerably low MW is
soluble in water although PTHF is known as hydrophobic polymer,
indicating that the hydrophobicity of PTHF is probably affected by
