TY - JOUR
T1 - Polystyrene-poly(propylene imine) dendrimers: synthesis, characterization, and association behavior of a new class of amphiphiles
AU - Hest, van, J.C.M.
AU - Delnoye, D.A.P.
AU - Baars, M.W.P.L.
AU - Roman Vas, C.
AU - Genderen, van, M.H.P.
AU - Meijer, E.W.
PY - 1996
Y1 - 1996
N2 - A new class of amphiphilic macromols. was prepd. by creating well-defined diblock copolymers of polystyrene (PS, Mn=3.2 * 103, Mw/Mn = 1.04) with poly(propyleneimine) dendrimers. A polystyrene core mol. with a primary amine end-group was prepd. by a quant. three-step modification procedure of acid-functionalized polystyrene. On this core mol., five different generations from PS-dendr-NH2 up to PS-dendr-(NH2)32 were constructed in high yields. The mol. structure of the block copolymers was analyzed in detail with NMR and IR spectroscopy and electrospray mass spectrometry. With cond. measurements and monolayer pressure-area isotherm detns., we obsd. generation-dependent amphiphilic behavior. Dynamic light scattering and transmission electron microscopy showed that amphiphile geometry had a distinct effect on aggregation behavior; this is in qual. agreement with Israelachvili's theory. Crit. assocn. concns. detd. with the pyrene probe luminescence technique were as low as 5 * 10-7 M. The amphiphiles presented here, therefore, show a resemblance to traditional block copolymers with regard to size and stability, and are similar to surfactants with respect to tuning of the shape
AB - A new class of amphiphilic macromols. was prepd. by creating well-defined diblock copolymers of polystyrene (PS, Mn=3.2 * 103, Mw/Mn = 1.04) with poly(propyleneimine) dendrimers. A polystyrene core mol. with a primary amine end-group was prepd. by a quant. three-step modification procedure of acid-functionalized polystyrene. On this core mol., five different generations from PS-dendr-NH2 up to PS-dendr-(NH2)32 were constructed in high yields. The mol. structure of the block copolymers was analyzed in detail with NMR and IR spectroscopy and electrospray mass spectrometry. With cond. measurements and monolayer pressure-area isotherm detns., we obsd. generation-dependent amphiphilic behavior. Dynamic light scattering and transmission electron microscopy showed that amphiphile geometry had a distinct effect on aggregation behavior; this is in qual. agreement with Israelachvili's theory. Crit. assocn. concns. detd. with the pyrene probe luminescence technique were as low as 5 * 10-7 M. The amphiphiles presented here, therefore, show a resemblance to traditional block copolymers with regard to size and stability, and are similar to surfactants with respect to tuning of the shape
U2 - 10.1002/chem.19960021221
DO - 10.1002/chem.19960021221
M3 - Article
VL - 2
SP - 1616
EP - 1626
JO - Chemistry : A European Journal
JF - Chemistry : A European Journal
SN - 0947-6539
IS - 12
ER -