Collapse transitions in thermosensitive multi-block copolymers: A Monte Carlo study

Rissanou, Anastassia N.; Tzeli, Despoina S.; Anastasiadis, Spiros H.; Bitsanis, Ioannis A.

doi:10.1063/1.4875694

Cited by 4 publications

(3 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another interesting direction for future work could be to fit other families of probability distributions, either generic [39] or theoretical [14,15], and to determine whether the CP estimates obtained from such distributions are more reliable and easier to compute than those obtained from fitted EGLD cdfs. Although the method we presented is aimed at accelerating efforts to elucidate the spatial organization of chromatin, the ability to estimate CPs efficiently from simulations of polymer chains may be also beneficial to research in topics as diverse as globule formation in multiblock copolymers [40] or reaction kinetics in macromolecules with reactive groups [41].…”

Section: Discussionmentioning

confidence: 99%

Efficient estimation of contact probabilities from inter-bead distance distributions in simulated polymer chains

Meluzzi

Arya

2015

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The estimation of contact probabilities (CP) from conformations of simulated bead-chain polymer models is a key step in methods that aim to elucidate the spatial organization of chromatin from analysis of experimentally determined contacts between different genomic loci. Although CPs can be estimated simply by counting contacts between beads in a sample of simulated chain conformations, reliable estimation of small CPs through this approach requires a large number of conformations, which can be computationally expensive to obtain. Here we describe an alternative computational method for estimating relatively small CPs without requiring large samples of chain conformations. In particular, we estimate the CPs from functional approximations to the cumulative distribution function (cdf) of the inter-bead distance for each pair of beads. These cdf approximations are obtained by fitting the extended generalized lambda distribution (EGLD) to inter-bead distances determined from a sample of chain conformations, which are in turn generated by Monte Carlo simulations. We find that CPs estimated from fitted EGLD cdfs are significantly more accurate than CPs estimated using contact counts from samples of limited size, and are more precise with all sample sizes, permitting as much as a tenfold reduction in conformation sample size for chains of 200 beads and samples smaller than 10(5) conformations. This method of CP estimation thus has potential to accelerate computational efforts to elucidate the spatial organization of chromatin.

show abstract

Section: Discussionmentioning

confidence: 99%

Efficient estimation of contact probabilities from inter-bead distance distributions in simulated polymer chains

Meluzzi

Arya

2015

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…Copolymers are directly related to critical technological applications; for example, they are utilized as thermoplastic elastomers, pressure-sensitive hot-melt adhesives, drug delivery systems, in the field of nanopatterning and surface modification, , polymer mixing, and so forth. Various studies based on analytical − or computational methods , have explored the properties of random copolymers, their phase behavior, and the order–disorder transition demonstrating the significance of their structural and chemical correlations. ,, In all these studies, due to the underlying chemical complexity, the need for accurate models is highlighted. Among copolymers, polybutadiene (PB) holds an unique position in the rubber industry.…”

Section: Introductionmentioning

confidence: 99%

Polybutadiene Copolymers via Atomistic and Systematic Coarse-Grained Simulations

et al. 2021

View full text Add to dashboard Cite

The systematic coarse graining of polymeric systems is a usual route in order to extend the range of spatiotemporal scales and systems accessible to molecular simulations. Here, we present a bottom-up methodology in order to obtain coarse-grained (CG) models for copolymers, derived from more than one species of monomers via detailed atomistic simulations. In the proposed scheme, each monomer type is represented as a different CG particle. The effective CG interactions are obtained via a dualstage multi-component iterative Boltzmann inversion optimization scheme, in which the single-component terms of the CG model are obtained from homopolymer simulations, whereas the interactions between different CGtype particles (mixed terms of the CG model) are obtained from the simulation of a symmetric composition copolymer. As an example, the proposed optimization scheme is applied on polybutadiene (PB) copolymers consisting of cis-1,4, trans-1,4, and vinyl-1,2 isomers. The derived CG PB copolymer model is examined with respect to its transferability across molecular weight and copolymer composition. In addition, using the newly derived CG model, various PB copolymers across a broad range of cis-1,4, trans-1,4, and vinyl-1,2 compositions are examined. Structural and dynamical properties of PB copolymers are presented. The vinyl component is found to have a large impact on the conformational properties of PB copolymer melts because of the different packing imposed by side groups. Standard composition mixing rules are used to predict the time mapping factors for the calculation of both segmental and center-of-mass dynamics of the PB copolymer, coming from the CG model.

show abstract

“…The concept of “small globules” showing a large variety of different globular morphologies in a single chain of finite length consisting of flexible and stiff segments was discussed for the first time in [33]. Computer simulations of different models for single chains of multiblock copolymers were performed in [34,35,36,37,38,39,40,41] to study morphological transitions, in particular the collapse of flexible-semiflexible multiblock copolymers in selective solvents [36], the collapse of flexible AB-multiblock copolymers in selective solvents [35,37,38,39,40,41], and the phase transitions in protein-like AB- and HPmultiblock copolymers [34]. Furthermore, a self-consistent-field theory was developed in [42] to study transitions in a rod-coil multiblock globule, and three different possible morphologies were identified: cols, amorphous globules, and nematic Liquid-Crystalline (LC) globules.…”

Section: Introductionmentioning

confidence: 99%

Diagrams of States of Single Flexible-Semiflexible Multi-Block Copolymer Chains: A Flat-Histogram Monte Carlo Study

et al. 2019

View full text Add to dashboard Cite

The combination of flexibility and semiflexibility in a single molecule is a powerful design principle both in nature and in materials science. We present results on the conformational behavior of a single multiblock-copolymer chain, consisting of equal amounts of Flexible (F) and Semiflexible (S) blocks with different affinity to an implicit solvent. We consider a manifold of macrostates defined by two terms in the total energy: intermonomer interaction energy and stiffness energy. To obtain diagrams of states (pseudo-phase diagrams), we performed flat-histogram Monte Carlo simulations using the Stochastic Approximation Monte Carlo algorithm (SAMC). We have accumulated two-Dimensional Density of States (2D DoS) functions (defined on the 2D manifold of macrostates) for a SF-multiblock-copolymer chain of length N = 64 with block lengths b = 4, 8, 16, and 32 in two different selective solvents. In an analysis of the canonical ensemble, we calculated the heat capacity and determined its maxima and the most probable morphologies in different regions of the state diagrams. These are rich in various, non-trivial morphologies, which are formed without any specific interactions, and depend on the block length and the type of solvent selectivity (preferring S or F blocks, respectively). We compared the diagrams with those for the non-selective solvent and reveal essential changes in some cases. Additionally, we implemented microcanonical analysis in the “conformational” microcanonical ( N V U , where U is the potential energy) and the true microcanonical ( N V E , where E is the total energy) ensembles with the aim to reveal and classify pseudo-phase transitions, occurring under the change of temperature.

show abstract

Collapse transitions in thermosensitive multi-block copolymers: A Monte Carlo study

Cited by 4 publications

References 42 publications

Efficient estimation of contact probabilities from inter-bead distance distributions in simulated polymer chains

Efficient estimation of contact probabilities from inter-bead distance distributions in simulated polymer chains

Polybutadiene Copolymers via Atomistic and Systematic Coarse-Grained Simulations

Diagrams of States of Single Flexible-Semiflexible Multi-Block Copolymer Chains: A Flat-Histogram Monte Carlo Study

Contact Info

Product

Resources

About