Thermoresponsive vesicular morphologies obtained by self-assemblies of hybrid oligosaccharide-block-poly(N-isopropylacrylamide) copolymer systems.
This work discusses the self-assembly properties of thermoresponsive hybrid oligosaccharide-block-poly(N-isopropylacrylamide) copolymer systems: maltoheptaose-block-poly(N-isopropylacrylamide) (Mal(7)-b-PNIPAM(n)) copolymers. Those systems at different molar masses and volume fractions were synthesized using Cu(I)-catalyzed 1,3-dipolar azide/alkyne cycloaddition, so-called "click" chemistry, between an alkynyl-functionalized maltoheptaose (1) and poly(N-isopropylacrylamide) having a terminal azido group (N(3)-PNIPAM(n)) prepared by atom transfer radical polymerization (ATRP). While the cloud point (T(cp)) of the N(3)-PNIPAM(n) ranged from 36.4 to 51.5 degrees C depending on the degree of polymerization, those obtained of the diblock copolymers ranged from 39.4 to 73.9 degrees C. The self-assembly of such systems is favored due to the hydrophobicity of the PNIPAM in water above the T(cp). While the N(3)-PNIPAM(n) present polydisperse globular shape with a mean diameter of 500 nm, well-defined vesicular morphologies with an approximate diameter of 300 nm are obtained in diblock copolymer systems. These results were obtained and confirmed using static and dynamic light scattering as well as imaging techniques such as transmission electron microscope experiments.
Centre de Recherche sur les Macromolécules Végétales (CERMAV, UPR-CNRS 5301) affiliated with Université Joseph Fourier, 38041 Grenoble Cedex 9, France.
Issei
I
Otsuka
Keita
K
Fuchise
Sami
S
Halila
Sébastien
S
Fort
Karim
K
Aissou
Isabelle
I
Pignot-Paintrand
Yougen
Y
Chen
Atsushi
A
Narumi
Toyoji
T
Kakuchi
Redouane
R
Borsali
D000178:Acrylamides / Q000737:chemistry*; D000180:Acrylic Resins; D002384:Catalysis; D003300:Copper / Q000737:chemistry; D005936:Glucans / Q000737:chemistry*; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013696:Temperature
D000178:Acrylamides; D000180:Acrylic Resins; D005936:Glucans; D009844:Oligosaccharides; D011108:Polymers; C052970:poly-N-isopropylacrylamide; C031146:maltoheptaose; D003300:Copper