Nonlinear Rheological Behaviors in Polymer Melts after Step Shear

Ruan, Yongjin; Lu, Yuyuan; An, Lijia; Wang, Zhen‐Gang

doi:10.1021/acs.macromol.9b00392

Cited by 12 publications

(12 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have made use of the contact maps to identify the main intra- and interchain peptide conformations in the system. With the advancement of machine learning methods, , the contact maps will have broader application prospects for more complex long-chain systems, like identifying knots , and linkings, , which are key contributing factors in problems related to protein elasticity and nonlinear rheology of polymers. , We have also developed a discrete-charge mean-field theory that considers the main contributing factors to the peptide brush height. Through the theory, we are able to better understand the competing interactions involved.…”

Section: Discussionmentioning

confidence: 99%

Sequence–Conformation Relationship of Zwitterionic Peptide Brushes: Theories and Simulations

Zhuang

2021

Macromolecules

View full text Add to dashboard Cite

Zwitterionic polymer brushes have broad applications in antifouling, biolubrication, and drug delivery. The charge distribution on polymers is critical to the structure and properties of surface-tethered zwitterionic polymer brushes. However, there is a lack of understanding of the relationship between the charge distribution and conformation in these systems, which is important for designing and predicting the functionality of controllable surface-tethered polymer brushes. Zwitterionic peptides with different sequences of charged amino acids are excellent model systems to elucidate such a charge–conformation relationship. By performing all-atom molecular dynamics (MD) simulations and developing a discrete-charge mean-field theory, we perform a systematic investigation on the effect of charge distribution on the conformations of zwitterionic peptide brushes. All-atom MD simulations reveal that the height of the peptide brush strongly depends on the distribution of the charges along the peptide chain. Contact map analysis reveals that the charge sequence also determines the preferred intrachain (loops and extended) and interchain (head-to-tail and parallel) structures. Through the theory developed by us, we show that the interchain electrostatic interactions are responsible for the contraction of peptide brushes with long charged blocks, while elasticity drives the contraction of peptide brushes with alternating-charged segments. This study provides a clear illustration of the factors influencing the sequence–conformation relationship of zwitterionic peptide brushes.

show abstract

Section: Discussionmentioning

confidence: 99%

Sequence–Conformation Relationship of Zwitterionic Peptide Brushes: Theories and Simulations

Zhuang

2021

Macromolecules

View full text Add to dashboard Cite

show abstract

“…We expect that the different types of entanglements identified in our work will have distinct contributions in affecting the dynamics of polymer melts, especially under large and fast deformations. In particular, the spatial distribution and relaxation rate of the different types of entanglements should play essential roles in all kinds of strain localization phenomena, such as melt fracture − and rupture of polymer films. , …”

Section: Discussionmentioning

confidence: 99%

Multiple Entanglements between Two Chains in Polymer Melts: An Analysis of Primitive Paths Based on Frenet Trihedron

Ruan,

Lu,

et al. 2024

Macromolecules

Self Cite

View full text Add to dashboard Cite

We propose an analysis of primitive paths for entangled polymers based on combining energy minimization with the Frenet trihedron geometric analysis. Using this method, which we abbreviate as FT-PPA, we identify the chain and monomer index associated with each entanglement, classify the different types of entanglements, and determine the fraction of each type under both equilibrium and shear conditions. Our analysis reveals that in entangled polymer melts, a pair of neighboring polymer chains can form multiple (two or more) entanglements (MuEs). The fraction of MuEs follows a very good exponential decay with the number of entanglements between the two entangled chains at equilibrium, with the rate of decay decreasing with increasing chain length. In addition, a significant fraction of entanglements are intervening entanglements (InEs), which are formed by a third chain between two MuEs on a tagged chain. We apply FT-PPA to shear banding in entangled polymer melts under fast shear deformation and show that the minimum in the spatial distribution of MuEs and InEs in the gradient direction, even at equilibrium, is strongly correlated with the center position of the fast band. This result supports our previous inference (

show abstract

“…At this time, the system exhibits different motion forms. Next, numerical simulation is used to analyze the influence of the parameter excitation amplitude f on the bifurcation behavior of the system [12]. The main parameter of the system (5) is 0 0 1, 2, 0.1, 0.05, 0.1( 1, 2,3, 4,5)…”

Section: Bifurcation Analysismentioning

confidence: 99%

Nonlinear Differential Equation in Anti-aging Test of Polymer Nanomaterials

Liu

2022

Applied Mathematics and Nonlinear Sciences

View full text Add to dashboard Cite

Rutile nano-TiO2 is a non-toxic and odorless inorganic UV shielding agent with excellent performance in polymer materials. This material absorbs part of the UV light energy through electronic transitions and releases it as heat or fluorescence. In this way, the molecular chain of the polymer material is prevented from being broken after absorbing high-energy ultraviolet light. So it has a certain antiaging effect. This article takes this material as the research object. We set up a molecular antiaging experiment for parametrically excited nonlinear differential equations. In this paper, the amplitude-frequency response of the system, the stability, and the bifurcation characteristics of the system are analyzed using the multiscale method. At the same time, we use numerical simulation to verify the theoretical analysis results. The research shows that the surface-treated nano-TiO2 has good dispersibility in polymer materials.

show abstract

Nonlinear Rheological Behaviors in Polymer Melts after Step Shear

Cited by 12 publications

References 49 publications

Sequence–Conformation Relationship of Zwitterionic Peptide Brushes: Theories and Simulations

Sequence–Conformation Relationship of Zwitterionic Peptide Brushes: Theories and Simulations

Multiple Entanglements between Two Chains in Polymer Melts: An Analysis of Primitive Paths Based on Frenet Trihedron

Nonlinear Differential Equation in Anti-aging Test of Polymer Nanomaterials

Contact Info

Product

Resources

About