“…M 93 A 94 and M 214 A 81 have a similar degree of polymerization of PAA and were chosen to study the effect of block composition on the subsequent aggregate morphology of PM-b-PAA. 36 Besides, the anisotropic morphology of dried micelles, especially indicated from the apparent dimensional contrast between cross-section height and in-plane diameter, implied the aggregated platelet-like structure as had been reported for other crystalline-coil BCPs. 1A).…”
Section: Aggregation Behavior Of Pm-b-paa and Its Inuential Factorsmentioning
confidence: 53%
“…For the XRD patterns of both M 107 A 5 and M 93 A 94 samples in Fig. 36 Despite the similar diffraction peak positions, the diffraction intensity was dramatically attenuated for M 93 A 94 as compared to M 107 A 5 . 44 Therefore, the self-assembled aggregates comprised crystalline-conned PM core with identical crystallization structures as bulk polyethylene.…”
Section: The Conned Crystallization Of Pm-b-paamentioning
confidence: 88%
“…1A). 36 The change in morphology with different block compositions was further veried by TEM analysis with M 93 A 94 and M 214 A 81 samples being dropped on a copper grid from 0.2 mg mL À1 DMF solution. 1B).…”
Section: Aggregation Behavior Of Pm-b-paa and Its Inuential Factorsmentioning
In this paper, we have systematically investigated the aggregation behavior, confined crystallization and controlled growth of a novel polyolefin analogue-containing block copolymers (BCPs), i.e., polymethylene-b-poly(acrylic acid) diblock copolymers (PM-b-PAA). On cooling from a homogenous DMF solution at 80 °C, PM-b-PAA was found to crystallize and aggregate with well-defined disk-like micelles. The aggregate behavior and in-plane morphology of PM-b-PAA could be easily controlled by modifying the block ratio, solution pH and solvent composition (DMF-water), by manipulating the crystallization of PM block and the stretching degree of solvated PAA corona. Further investigation of the crystalline feature of PM-b-PAA indicated that the crystallization of PM was retarded by tethered amorphous PAA segments. The crystalline micelle could construct a nano-confined environment with PM folding as the core into a thickness of the mono-layered polyethylene. Finally, when cultured in dilute DMF solution at 50 °C, the initial crystalline micelles, being as self-seeds, could follow a living growth mechanism and develop into single crystals, with well-defined lozenge-shaped morphology.
“…M 93 A 94 and M 214 A 81 have a similar degree of polymerization of PAA and were chosen to study the effect of block composition on the subsequent aggregate morphology of PM-b-PAA. 36 Besides, the anisotropic morphology of dried micelles, especially indicated from the apparent dimensional contrast between cross-section height and in-plane diameter, implied the aggregated platelet-like structure as had been reported for other crystalline-coil BCPs. 1A).…”
Section: Aggregation Behavior Of Pm-b-paa and Its Inuential Factorsmentioning
confidence: 53%
“…For the XRD patterns of both M 107 A 5 and M 93 A 94 samples in Fig. 36 Despite the similar diffraction peak positions, the diffraction intensity was dramatically attenuated for M 93 A 94 as compared to M 107 A 5 . 44 Therefore, the self-assembled aggregates comprised crystalline-conned PM core with identical crystallization structures as bulk polyethylene.…”
Section: The Conned Crystallization Of Pm-b-paamentioning
confidence: 88%
“…1A). 36 The change in morphology with different block compositions was further veried by TEM analysis with M 93 A 94 and M 214 A 81 samples being dropped on a copper grid from 0.2 mg mL À1 DMF solution. 1B).…”
Section: Aggregation Behavior Of Pm-b-paa and Its Inuential Factorsmentioning
In this paper, we have systematically investigated the aggregation behavior, confined crystallization and controlled growth of a novel polyolefin analogue-containing block copolymers (BCPs), i.e., polymethylene-b-poly(acrylic acid) diblock copolymers (PM-b-PAA). On cooling from a homogenous DMF solution at 80 °C, PM-b-PAA was found to crystallize and aggregate with well-defined disk-like micelles. The aggregate behavior and in-plane morphology of PM-b-PAA could be easily controlled by modifying the block ratio, solution pH and solvent composition (DMF-water), by manipulating the crystallization of PM block and the stretching degree of solvated PAA corona. Further investigation of the crystalline feature of PM-b-PAA indicated that the crystallization of PM was retarded by tethered amorphous PAA segments. The crystalline micelle could construct a nano-confined environment with PM folding as the core into a thickness of the mono-layered polyethylene. Finally, when cultured in dilute DMF solution at 50 °C, the initial crystalline micelles, being as self-seeds, could follow a living growth mechanism and develop into single crystals, with well-defined lozenge-shaped morphology.
Crystallization-driven self-assembly of polyethylene-b-poly(tert-butylacrylate) (PE-b-PtBA) block copolymers (BCPs) in N,N-dimethyl formamide (DMF) was studied. It is found that all three PE-b-PtBA BCPs used in this work can self-assemble into one-dimensional crystalline cylindrical micelles. When the BCP solution is cooled to crystallization temperature (Tc) from 130 °C, the seed micelles may be produced via two competitive processes in the initial period: stepwise micellization/crystallization and simultaneous crystallization/micellization. Subsequently, the seed micelles can undergo growth driven by the epitaxial crystallization of the unimers. The lengths of both the seed micelles and the grown micelles are longer for the BCP with a longer PtBA block at a higher Tc. Quasi-living growth of the PE-b-PtBA crystalline cylindrical micelles is achieved at a higher Tc. A longer PtBA block evidently retards the attachment of unimers to the crystalline micelles, leading to a slower growth rate.
“…Polyferrocenylsilane and polythiophene contained block copolymers formed cylindrical micelles via the living self‐assembly . Polyethylene contained block copolymers can assemble into disk‐like micelles, patchy corona worm‐like micelles, nanoplate and nanodiscs . The isotactic polystyrene block contained copolymer assembled into petal‐like micelles in selective solutions …”
Bamboo leaf shaped poly(ethylene oxide)-b-poly(ϵ-caprolactone) (PEO-b-PCL) sheets were prepared via crystallization-driven self-assembly. By selecting an appropriate mixed solvent, the polymer sheets, with a PCL single-crystal layer sandwiched by two PEO layers, were obtained efficiently. The morphology and structure of the sheets were characterized by microscopes and diffraction techniques. As a non-spherical model particle, endocytosis of the sheets was investigated on RAW 264.7, U937, HUVECs, HeLa, and 293 T cells. The polymer sheets, just like wafers for cells, displayed a selective internalization to different cells, which showed a potential application in accurate cell targeting drug delivery and imaging.
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