Formation of Stacked Three-Dimensional Polymer “Single Crystals”

Guo, Zhenjiang; Yan, Shouke; Reiter, Günter

doi:10.1021/acs.macromol.1c00081

Cited by 12 publications

(15 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, for a constant T SS but varying T C , L can be expressed as L 2 ≈ 1/h•∆c. Increasing T C leads to a reduction of M C and thus to platelets with smaller L. If η is increasing with T C , as observed, L decreases even more [17,36,46,47].…”

Section: Resultssupporting

confidence: 65%

See 1 more Smart Citation

Self-Seeding Procedure for Obtaining Stacked Block Copolymer Lamellar Crystals in Solution

2021

Self Cite

View full text Add to dashboard Cite

We examined the formation of self-seeded platelet-like crystals from polystyrene-block-polyethylene oxide (PS-b-PEO) diblock copolymers in toluene as a function of polymer concentration (c), crystallization temperature (TC), and self-seeding temperature (TSS). We showed that the number (N) of platelet-like crystals and their mean lateral size (L) can be controlled through a self-seeding procedure. As (homogeneous) nucleation was circumvented by the self-seeding procedure, N did not depend on TC. N increased linearly with c and decayed exponentially with TSS but was not affected significantly by the time the sample was kept at TSS. The solubility limit of PS-b-PEO in toluene (c*), which was derived from the linear extrapolation of Nc→ 0 and from the total deposited mass of the platelets per area (MCc→0), depended on TC. We have also demonstrated that at low N, stacks consisting of a (large) number (η) of uniquely oriented lamellae can be achieved. At a given TC, L was controlled by N and η as well as by ∆c=c−c∗. Thus, besides being able to predict size and number of platelet-like crystals, the self-seeding procedure also allowed control of the number of stacked lamellae in these crystals.

show abstract

Section: Resultssupporting

confidence: 65%

“…Increasing

leads to a reduction of

and thus to platelets with smaller

. If

is increasing with

, as observed,

decreases even more [ 17 , 36 , 46 , 47 ].…”

Section: Resultsmentioning

confidence: 58%

Self-Seeding Procedure for Obtaining Stacked Block Copolymer Lamellar Crystals in Solution

2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…This unambiguously demonstrates that the iPP bc plane is in contact with the iPS film and the (040) lattice plane of iPP involves in the parallel chain epitaxy. Therefore, the epitaxy between iPS and iPP is based on a two-dimensional lattice matching, as depicted in Figure . − …”

Section: Results and Discussionmentioning

confidence: 99%

Temperature-Dependent Reversibility of Epitaxy between Isotactic Polystyrene and Polypropylene

et al. 2021

Self Cite

View full text Add to dashboard Cite

Epitaxial crystallization of isotactic polystyrene (iPS) on the oriented isotactic polypropylene (iPP) substrate and the reverse process, that is, epitaxial growth of iPP crystals on the oriented iPS film initially generated by epitaxy of it on iPP, have been investigated through transmission electron and atomic force microscopies. Epitaxy of iPS on the ordered iPP substrate was achieved by cold crystallization of an amorphous thin film at 130 °C for 2 h. The results indicate that epitaxy of iPS on the iPP substrate has parallel chain relationship. Epitaxial growth of iPP on the oriented iPS film was realized by selective melting of the iPP in the epitaxial iPP/iPS system at 190 °C for 5 min and then crystallizing at varied temperatures. It was found that oriented recrystallization of iPP on the itself-induced iPS epitaxially oriented substrate occurs at temperatures below 30 °C and produces exactly the same parallel mutual chain alignment, indicating the reversibility of epitaxy between iPP and iPS. It does, however, not happen at temperatures over 60 °C, reflecting a temperature-dependent epitaxial growth of iPP on iPS oriented films. This was explained by secondary nucleation and indicates that a larger dimension of substrate crystals than the depositing epitaxial ones is necessary for the occurrence of polymer epitaxy. This provides a theoretical basis for the substrate selection of polymer epitaxies.

show abstract

“…23 Interestingly, threedimensional polymer "single crystals" with a total height of several micrometers could be generated, corresponding to a crystalline structure consisting of hundreds of superposed and uniquely oriented lamellae. 27 However, so far, it has not been possible to switch-on or to switch-off self-induced nucleation at particular locations of a basal lamella. Nucleation at junctions is a stochastic process leading to a rather random and unpredictable distribution of the resulting stacks of lamellae.…”

Section: ■ Introductionmentioning

confidence: 99%

“…On the basis of the self-induced nucleation mechanism, several systematic studies explored possibilities for the growth of stacks of homopolymer and block copolymer lamellar crystals on a basal lamella. − Key parameters that determine the kinetics of vertical growth have been identified: the probability of self-induced nucleation; the detachment probability of crystalline stems; or the rate of influx of polymers toward the growth front . Interestingly, three-dimensional polymer “single crystals” with a total height of several micrometers could be generated, corresponding to a crystalline structure consisting of hundreds of superposed and uniquely oriented lamellae …”

Section: Introductionmentioning

confidence: 99%

Controlled Switching from the Growth of Monolamellar Polymer Crystals to the Formation of Stacks of Uniquely Oriented Lamellae

et al. 2021

Self Cite

View full text Add to dashboard Cite

We have used a rationally designed two-step crystallization approach to induce the formation of stacks of superposed and uniquely oriented flat-on polymer lamellae exclusively and controllably at the periphery of monolamellar polymer crystals. The probability of initiating such stacks of lamellar crystals via self-induced nucleation was controlled by the crystallization temperature, which in turn, determined the width of crystalline branches through the Mullins-Sekerka instability. We employed this approach for the formation of a "fence" of stacks of lamellar crystals at the periphery of monolamellar stereocomplex single crystals of poly(L-lactide) and poly(D-lactide). The resulting morphology resembled a "pseudo hollow crystal" with an almost empty interior of a size controllable by crystallization time. We believe that such an approach can be applied also for other crystallizable polymers.

show abstract

Formation of Stacked Three-Dimensional Polymer “Single Crystals”

Cited by 12 publications

References 42 publications

Self-Seeding Procedure for Obtaining Stacked Block Copolymer Lamellar Crystals in Solution

Self-Seeding Procedure for Obtaining Stacked Block Copolymer Lamellar Crystals in Solution

Temperature-Dependent Reversibility of Epitaxy between Isotactic Polystyrene and Polypropylene

Controlled Switching from the Growth of Monolamellar Polymer Crystals to the Formation of Stacks of Uniquely Oriented Lamellae

Contact Info

Product

Resources

About