Composition dependence of nanophase‐separated structures formed by star‐shaped terpolymers of the A_1.0B_1.0C_X type

Abstract

Several hierarchical nanophase-separated structures have been observed for a series of ABC star-shaped terpolymers by transmission electron microscopy (TEM) and electron computerized tomography (3D-TEM). The seven terpolymers synthesized are composed of polyisoprene (I), polystyrene (S), and poly(2-vinylpyridine) (P), their volume fraction ratios of I:S:P are 1:1:X, where X equals 0.2, 0.4, 0.7, 1.2, 1.9, 3.0, and 4.9, respectively, and additional four samples were prepared by blending each two parent terpolymers. From morphological observation by TEM and tomography, a terpolymer with X of 0.2 shows lamellar structure with spheres at the interface, those with X ranging from 0.4 to 1.9 show cylindrical structures with twodimensional tiling, while those with X of 3.0 and 4.9 show hierarchical cylinders-inlamella structure. Two the other terpolymer samples with X of 7.9 and 10 were produced by blending a P homopolymer with the terpolymer I 1.0 S 1.0 P 4.9 , and they both exhibited columnar piled disk cylinders in P matrix. From the comparison of the present results with the predictions by the Monte-Carlo simulation, it was confirmed that the observed nanophase-separated structures of the ISP star-shaped terpolymers are mostly in good agreement with the prediction.

Jewelry Box of Morphologies with Mesoscopic Length Scales – ABC Star‐shaped Terpolymers

“…The same morphology was also found for a block copolymer with hydrogen‐bonded amphiphilic plasticizing compound, i.e. pentadecylphenol 51. The sample, I 1.0 S 1.0 P 4.9 , also reveals essentially the same kind of hierarchical morphology.…”

Kaleidoscopic tilings, networks and hierarchical structures in blends of 3-miktoarm star terpolymers

“…As a consequence, a sequence of cylindrical structures following various polygonal tiling patterns appears. This sequence of tilings has been predicted from all the earlier mentioned theoretical studies and has been found in a number of experimental ABC 3-miktoarm star terpolymer systems [13][14][15]. Recently, experimental results showing interesting new morphologies are emerging involving blends of ABC 3-miktoarm star terpolymers with other polymer species.…”

Self-Assembly of Asymmetrically Interacting ABC Star Triblock Copolymer Melts

“…From our simulations, the resulting phase behavior is in good agreement with these experimental measurements when 0.7 < x < 2.0. At higher asymmetries, Takano et al46 observed an L+S phase in I 1.0 S 1.0 P 0.2 system, and an L+C phase in I 1.0 S 1.0 P 3.0 and I 1.0 S 1.0 P 4.9 copolymers.However, in our calculations, the LAM phase dominates the regions. This might be attributed to the relatively weak interaction parameters of χ AB N or χ BC N in our simulations so that a further segregation between components A and B (or B and C) can not occur.…”