Kinetics of Supramolecular Polymerization: MSOA and HG Mechanisms

Multistage open association (MSOA) and helical growth (HG) mechanisms describe the linear growth of supramolecular polymer chains and the helical growth of supramolecular chains with the intra-assemble cooperative effect, respectively. Both mechanisms were proposed by Ciferri. Assuming that supramolecular polymerization follows the step-growth and the interaction between repeat units is independent of molecular weight, the kinetics of MSOA and HG can be mathematically analyzed. In this paper the relationships among degree of polymerization (DP), unimer concentration (C0), and equilibrium constant (K) for MSOA and DP , concentration of helical polymer ( h C ), and nucleation factor (σ ) for HG were derived.

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Oriented arrangement of simple monomers enabled by confinement: towards living supramolecular polymerization

Nature Communications ◽

10.1038/s41467-021-22827-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Yingtong Zong ◽

Si-Min Xu ◽

Wenying Shi ◽

Chao Lu

Keyword(s):

Activation Barrier ◽

Degree Of Polymerization ◽

Supramolecular Polymer ◽

Energy Principle ◽

Spontaneous Nucleation ◽

Pyrene Derivatives ◽

Multifunctional Molecules ◽

Double Hydroxide ◽

Supramolecular Polymerization ◽

Kinetics Of

AbstractThe living supramolecular polymerization technique provides an exciting research avenue. However, in comparison with the thermodynamic spontaneous nucleation, using simple monomers to realize living supramolecular polymerization is hardly possible from an energy principle. This is because the activation barrier of kinetically trapped simple monomer (nucleation step) is insufficiently high to control the kinetics of subsequent elongation. Here, with the benefit of the confinement from the layered double hydroxide (LDH) nanomaterial, various simple monomers, (such as benzene, naphthalene and pyrene derivatives) successfully form living supramolecular polymer (LSP) with length control and narrow dispersity. The degree of polymerization can reach ~6000. Kinetics studies reveal LDH overcomes a huge energy barrier to inhibit undesired spontaneous nucleation of monomers and disassembly of metastable states. The universality of this strategy will usher exploration into other multifunctional molecules and promote the development of functional LSP.

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SuFExable Polymers with Helical Structures Derived from Thionyl Tetrafluoride (SOF4)

10.26434/chemrxiv.10005758 ◽

2019 ◽

Author(s):

Suhua Li ◽

Gencheng Li ◽

Bing Gao ◽

Sidharam P. Pujari ◽

Xiaoyan Chen ◽

...

Keyword(s):

Functional Polymers ◽

Polymer Chains ◽

New Materials ◽

Helical Structures ◽

Polymer Backbone ◽

Silyl Ethers ◽

Helical Polymer ◽

Key Characteristics ◽

Post Modification ◽

Individual Polymer

The first SuFEx click chemistry synthesis of SOF<sub>4</sub>-derived copolymers based upon the polymerization of bis(iminosulfur oxydifluorides) and bis(aryl silyl ethers) is described. This novel class of SuFEx polymer presents two key characteristics: First, the newly created [-N=S(=O)F-O-] polymer backbone linkages are themselves SuFExable and primed to undergo further high-yielding and precise SuFEx-based post-modification with phenols or amines to yield branched functional polymers. Second, studies of individual polymer chains of several of these new materials indicate the presence of helical polymer structures, which itself suggests a preferential approach of new monomers onto the growing polymer chain upon the formation of the stereogenic linking moiety.

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Simulations of High-Strain Electrostrictive Chlorinated Terpolymers

MRS Proceedings ◽

10.1557/proc-785-d3.7 ◽

2003 ◽

Vol 785 ◽

Author(s):

George J. Kavarnos ◽

Thomas Ramotowski

Keyword(s):

Vinylidene Fluoride ◽

High Strain ◽

Polymer Chains ◽

X Ray Diffraction ◽

X Ray ◽

Lamellar Structures ◽

Annealing Conditions ◽

Poly Vinylidene Fluoride ◽

Electromechanical Responses ◽

Kinetics Of

ABSTRACTChlorinated poly(vinylidene fluoride/trifluoroethylene) terpolymers are remarkable examples of high strain electrostrictive materials. These polymers are synthesized by copolymerizing vinylidene fluoride and trifluoroethylene with small levels of a third chlorinated monomer. The electromechanical responses of these materials are believed to originate from the chlorine atom, which, by its presence in the polymer chains and by virtue of its large van der Waals radius, destroys the long-range crystalline polar macro-domains and transforms the polymer from a normal to a high-strain relaxor ferroelectric. To exploit the strain properties of the terpolymer, it is desirable to understand the structural implications resulting from the presence of the chlorinated monomer. To this end, computations have been performed on model superlattices of terpolymers using quantum-mechanical based force fields. The focus has been on determining the energetics and kinetics of crystallization of the various polymorphs that have been identified by x-ray diffraction and fourier transform infrared spectroscopy. The chlorinated monomer is shown to act as a defect that can be incorporated into the lamellar structures of annealed terpolymer without a high cost in energy. The degree of incorporation of the chlorinated monomer into the crystal lattice is controlled by annealing conditions and ultimately determines the ferroelectric behavior of the terpolymers.

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Poly(glycerol-sebacate) bioelastomers-kinetics of step-growth reactions using Fourier Transform (FT)-Raman spectroscopy

Journal of Applied Polymer Science ◽

10.1002/app.37719 ◽

2012 ◽

Vol 127 (5) ◽

pp. 3980-3986 ◽

Cited By ~ 19

Author(s):

Raju Maliger ◽

Peter J. Halley ◽

Justin J. Cooper-White

Keyword(s):

Raman Spectroscopy ◽

Fourier Transform ◽

Ft Raman Spectroscopy ◽

Step Growth ◽

Kinetics Of ◽

Ft Raman

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The kinetics of the polymerization of styrene initiated by n -butyl lithium in hydrocarbon media

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1962.0138 ◽

1962 ◽

Vol 268 (1333) ◽

pp. 260-275 ◽

Cited By ~ 16

Keyword(s):

Degree Of Polymerization ◽

Complete Conversion ◽

Initiator Concentration ◽

Butyl Lithium ◽

Initiation And Propagation ◽

Quantitative Results ◽

Kinetics Of ◽

Hydrocarbon Media

The kinetics of the polymerization of styrene initiated by n-butyl lithium in hydrocarbon media has been studied under conditions where both initiation and propagation of growing chains takes place simultaneously and in the absence of a termination reaction. Under the conditions employed, the initiator is incompletely consumed at complete conversion of monomer to polymer and consequently the degree of polymerization of the polystyrene is greater than the ratio of monomer to initiator concentration. The quantitative results support the mechanism previously proposed by Worsfold & By water for this polymerization.

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Kinetics of polymer crystallization - II. Growth régimes

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1988.0044 ◽

1988 ◽

Vol 416 (1851) ◽

pp. 463-476 ◽

Cited By ~ 15

Keyword(s):

Growth Rate ◽

Continuum Model ◽

Continuum Limit ◽

Polymer Chains ◽

Lamellar Crystal ◽

Folding Rate ◽

Edge Roughness ◽

State Growth ◽

Kinetics Of ◽

The Continuum

From the models of paper I, exact expressions are found for the steady-state growth rate of a portion of the edge of a lamellar crystal in terms of the number of polymer segments M in the portion, the nucleation rate α on the edge and the folding rate v of polymer chains. Both hexagonal and square crystal structures are analysed. Simpler expressions are given in various limiting cases or régimes. One such régime is the continuum model of Bennett et al. (J. statist. Phys . 24, 419 (1981)). We find that the growth rates in our models differ substantially from this continuum limit when edge roughness is significant. The continuum growth rate provides an exact upper bound on the growth rate in Frank’s model (Frank, F. C. J. Cryst. Growth 22, 233 (1974)), which is sometimes exceeded by Frank’s approximation.

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Morphology, Crystalline Structure and Isothermal Crystallization Kinetics of Polybutylene Terephthalate/Montmorillonite Nanocomposites

Polymers and Polymer Composites ◽

10.1177/096739110501300105 ◽

2005 ◽

Vol 13 (1) ◽

pp. 61-71 ◽

Cited By ~ 5

Author(s):

Defeng Wu ◽

Chixing Zhou ◽

Xie Fan ◽

Dalian Mao ◽

Zhang Bian

Keyword(s):

Activation Energy ◽

Crystallization Kinetics ◽

Crystallization Temperature ◽

Isothermal Crystallization ◽

Polymer Chains ◽

Isothermal Crystallization Kinetics ◽

Clay Particles ◽

Nucleation Sites ◽

Kinetics Of ◽

Montmorillonite Nanocomposites

The melt intercalation method was employed to prepare poly(butylene terepathalate)/montmorillonite nanocomposites, and their microstructure was characterized by wide angle X-ray diffraction and transmission electron microscopy. The XRD results showed that the crystalline plane such as (010), (111), (100) was smaller than that of pristine PBT, which indicates that the crystallite size of PBT in the nanocomposites could be diminished by adding clay. Moreover, the isothermal crystallization kinetics of PBT and PBT/MMT nanocomposites was investigated by differential scanning calorimetry (DSC). During isothermal crystallization, the development of crystallinity with time was analysed by the Avrami equation. The results show that very small amounts of clay dramatically increased the rate of crystallization and high clay concentrations reduced the rate of crystallization at the low crystallization temperatures. At low concentrations of clay, the distance between dispersed platelets was large so it was relatively easy for the additional nucleation sites to incorporate surrounding polymer, and the crystal nucleus was formatted easily. However, at high concentrations of clay, the diffusion of polymer chains to the growing crystallites was hindered by large clay particles, despite the formation of additional nucleation sites by the clay layers. At the higher crystallization temperature, the crystallization of the nanocomposites was slower than that of the pure PBT under the experimental conditions, which means that with the increase in chains mobility at the high crystallization temperature, the crystal nuclei are harder to format, and the hindering effect of clay particles on the polymer chains was stronger than the nucleating effect of the layers. In addition, the activation energies of crystallization for PBT and its nanocomposites were calculated by the Arrhenius relationship, and the results showed that the nanocomposites with a low clay content had the lower activation energy values than PBT, while high amounts of clay increased the activation energy of PBT.

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