TY - JOUR
T1 - Synthesis and morphological behavior of model linear and miktoarm star copolymers of 2-methyl-1,3-pentadiene and styrene
AU - Mavroudis, Anastasios
AU - Avgeropoulos, Apostolos
AU - Hadjichristidis, Nikolaos
AU - Thomas, Edwin L.
AU - Lohse, David J.
PY - 2003/5/20
Y1 - 2003/5/20
N2 - Three linear diblock copolymers (PS-b-P2MP), two 3-miktoarm [PS(P2MP)2] copolymers, and two 4-miktoarm star copolymers [PS(P2MP)3] of styrene (S) and 2-methyl-1,3-pentadiene (2MP) were synthesized by anionic polymerization/high vacuum techniques and controlled chlorosilane chemistry. Molecular characterization of the samples was carried out by size exclusion chromatography (SEC), membrane osmometry (MO), low-angle laser light scattering (LALLS), and 1H NMR spectroscopy, and indicated a high degree of molecular and compositional homogeneity. All samples had approximately the same total M̄w (∼100 000), different compositions, and high 1,4-microstructure for the P2MP blocks. The morphological behavior was determined via transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and differential scanning calorimetry (DSC). The experimental results were compared with those found for PS/PI block copolymer systems and with Milner's theoretical prediction. Significant discrepancies were found. Also, it is the first time that two morphologies (lamellae/double gyroid) coexist in a neat material, and especially in a 4-miktoarm star copolymer.
AB - Three linear diblock copolymers (PS-b-P2MP), two 3-miktoarm [PS(P2MP)2] copolymers, and two 4-miktoarm star copolymers [PS(P2MP)3] of styrene (S) and 2-methyl-1,3-pentadiene (2MP) were synthesized by anionic polymerization/high vacuum techniques and controlled chlorosilane chemistry. Molecular characterization of the samples was carried out by size exclusion chromatography (SEC), membrane osmometry (MO), low-angle laser light scattering (LALLS), and 1H NMR spectroscopy, and indicated a high degree of molecular and compositional homogeneity. All samples had approximately the same total M̄w (∼100 000), different compositions, and high 1,4-microstructure for the P2MP blocks. The morphological behavior was determined via transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and differential scanning calorimetry (DSC). The experimental results were compared with those found for PS/PI block copolymer systems and with Milner's theoretical prediction. Significant discrepancies were found. Also, it is the first time that two morphologies (lamellae/double gyroid) coexist in a neat material, and especially in a 4-miktoarm star copolymer.
UR - http://www.scopus.com/inward/record.url?scp=0037837478&partnerID=8YFLogxK
U2 - 10.1021/cm021360j
DO - 10.1021/cm021360j
M3 - Article
AN - SCOPUS:0037837478
SN - 0897-4756
VL - 15
SP - 1976
EP - 1983
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 10
ER -