Synthesis, characterization and self‐assembly of well‐defined linear heptablock quaterpolymers

Abstract

Two well‐defined heptablock quaterpolymers of the ABCDCBA type [Α: polystyrene (PS), B: poly(butadiene) with ∼90% 1,4‐microstructure (PB1,4), C: poly(isoprene) with ∼55% 3,4‐microstructure (PI3,4) and D: poly(dimethylsiloxane) (PDMS)] were synthesized by combining anionic polymerization high vacuum techniques and hydrosilylation/chlorosilane chemistry. All intermediates and final products were characterized by size exclusion chromatography, membrane osmometry, and proton nuclear magnetic resonance spectroscopy. Fourier transform infrared spectroscopy was used to further verify the chemical modification reaction of the difunctional PDMS. The self‐assembly in bulk of these novel heptablock quarterpolymers, studied by transmission electron microscopy and small angle X‐ray scattering, revealed 3‐phase 4‐layer alternating lamellae morphology of PS, PB1,4, and mixed PI3,4/PDMS domains. Differential scanning calorimetry was used to further confirm the miscibility of PI3,4 and PDMS blocks. It is the first time that PDMS is the central segment in such multiblock polymers (≥3 chemically different blocks). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1443–1449

Alternating Gyroid Network Structure in an ABC Miktoarm Terpolymer Comprised of Polystyrene and Two Polydienes

“…Furthermore, it should be mentioned that in such ABC linear terpolymers of the PS- b -PB 1,4 - b -PI 3,4 sequence our research group has managed [ 48 ] to identify the core-shell DG morphology concluding to the fact that the PI segment with the specific percentage of 3,4-microstructure is actually leading to a relatively high Flory–Huggins interaction parameter not only with PS but also with PB 1,4 . We have also demonstrated the stability of the three-phase four-layer lamellar structure by synthesizing heptablock quaterpolymers of the sequence PS- b -PB 1,4 - b -PI 3,4 - b -PDMS- b -PI 3,4 - b -PB 1,4 - b -PS [ 49 ]. The results from this specific work [ 49 ] indicated that the PI 3,4 and PDMS blocks are miscible, verifying our assumption of high value for the Flory–Huggins interaction parameter between the specific PI and PS or PB 1,4 .…”

“…We have also demonstrated the stability of the three-phase four-layer lamellar structure by synthesizing heptablock quaterpolymers of the sequence PS- b -PB 1,4 - b -PI 3,4 - b -PDMS- b -PI 3,4 - b -PB 1,4 - b -PS [ 49 ]. The results from this specific work [ 49 ] indicated that the PI 3,4 and PDMS blocks are miscible, verifying our assumption of high value for the Flory–Huggins interaction parameter between the specific PI and PS or PB 1,4 .…”

Self-Assembly of Low-Molecular-Weight Asymmetric Linear Triblock Terpolymers: How Low Can We Go?

“…Table 1 summarizes the data on already reported linear triblock terpolymers in the literature [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 ], and, more specifically, block sequence, number (or weight) average molecular weight range and the annealing conditions used, together with the corresponding reference. It is straightf...…”

Segregation of Maghemite Nanoparticles within Symmetric Diblock Copolymer and Triblock Terpolymer Patterns under Solvent Vapor Annealing

“…The microstructures of the polydienes are similar (as calculated by proton nuclear magnetic resonance spectroscopy, 1 H-NMR spectroscopy). Full detailed synthesis of the terpolymers is described in the literature [35][36][37]. Scheme 1 shows the reactions for the synthesis of the triblock terpolymers.…”

“…The triblock terpolymers displayed strongly incompatible and microphase separated components, (PS, PB 1,4 , and PI 3,4 ), where the two polydienes exhibit specific geometric isomerisms (high −1.4 for PB (~92%) and relatively high −3.4 for PI (~60%)). More specifically, PB exhibits approximately 92% −1.4 microstructure and 8% −1.2, whereas the PI is enriched in −3.4 microstructure (~60%),~25% corresponds to −1.4, and~15% to −1.2 microstructures, respectively [35][36][37]. The incorporation of iron oxide NPs (IONPs) and how their presence affects the generated terpolymer/NPs hybrid structure in comparison to corresponding diblock copolymer/NPs systems is discussed.…”