byproduct does not have this absorption, it was easy to differentiate the star polymer
from the linear polymer by GPC with UV detection and to optimize conditions for
the selective synthesis of the star polymer. It turned out that the polymerization of
the methyl ester monomer 14c at 10
C, which was higher than the optimized
temperature (À10
C) for the synthesis of linear poly14c with LiHMDS from a
monofunctional initiator, yielded the star polyamide with controlled molecular
weight and narrow molecular weight distribution up to the feed ratio of [14c] 0 /
[29] 0 of 120. Under the optimized conditions, a variety of well-defined tetra-armed
star-shaped poly(N-substituted p-benzamide)s, including block poly( p-benzamide)
s with different N-substituents, and poly(N-substituted m-benzamide)s, were synthesized by using tetrafunctional initiator 29 [72].
Star polyethers have been synthesized by a core-first method. AB 2 - and A 2 B-type
mikto-arm star copolymers consisting of aromatic polyether arms as the A segment
and polystyrene arms as the B segment were synthesized by using orthogonal
trifunctional initiators (Scheme 32) [73].
Scheme 30 Synthesis of star-shaped aromatic polyamide by chain-growth condensation polymerization of 14a with 1,3,5-tris(4-phenyloxycarbonylbenzyloxy)benzene (28)
Scheme 31 Synthesis of star-shaped aromatic polyamide by chain-growth condensation polymerization of 14c with porphyrin-cored tetrafunctional initiator 29
Chain-Growth Condensation Polymerization for Controlled Synthesis of Polymers
215
from the linear polymer by GPC with UV detection and to optimize conditions for
the selective synthesis of the star polymer. It turned out that the polymerization of
the methyl ester monomer 14c at 10
C, which was higher than the optimized
temperature (À10
C) for the synthesis of linear poly14c with LiHMDS from a
monofunctional initiator, yielded the star polyamide with controlled molecular
weight and narrow molecular weight distribution up to the feed ratio of [14c] 0 /
[29] 0 of 120. Under the optimized conditions, a variety of well-defined tetra-armed
star-shaped poly(N-substituted p-benzamide)s, including block poly( p-benzamide)
s with different N-substituents, and poly(N-substituted m-benzamide)s, were synthesized by using tetrafunctional initiator 29 [72].
Star polyethers have been synthesized by a core-first method. AB 2 - and A 2 B-type
mikto-arm star copolymers consisting of aromatic polyether arms as the A segment
and polystyrene arms as the B segment were synthesized by using orthogonal
trifunctional initiators (Scheme 32) [73].
Scheme 30 Synthesis of star-shaped aromatic polyamide by chain-growth condensation polymerization of 14a with 1,3,5-tris(4-phenyloxycarbonylbenzyloxy)benzene (28)
Scheme 31 Synthesis of star-shaped aromatic polyamide by chain-growth condensation polymerization of 14c with porphyrin-cored tetrafunctional initiator 29
Chain-Growth Condensation Polymerization for Controlled Synthesis of Polymers
215