Molecular view of polymer flow into a strongly attractive slit

Baljon, Arlette R. C.; Lee, Jae Youn; Loring, Roger F.

doi:10.1063/1.480248

Cited by 29 publications

(19 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They also exhibit superior mechanical properties,1–3 improved solvent resistance,4 enhanced ionic conductivity,5 reduced flammability,6 and enhance the biodegradability of biodegradable polymers 7. These materials are important model systems for study of the structure and properties of polymers in confined environments 8–12. In an intercalated nanocomposite, extended polymer chains remain between the host layers, whereas in an exfoliated hybrid silicate layer they are randomly dispersed in a continuous polymer matrix, such that the interlayer distance is comparable to the radius of the gyration of polymers 13…”

Section: Introductionmentioning

confidence: 99%

A new thermoplastic vulcanizate (TPV)/organoclay nanocomposite: Preparation, characterization, and properties

Mishra

Kim

et al. 2004

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

The preparation, characterization, and properties of the new thermoplastic vulcanizate (TPV)/organoclay nanocomposites are reported in this article. The nanocomposites were prepared by the melt intercalation method. The organoclay was first treated with glycidyl methacrylate, which acts as a swelling agent for organoclays, as well as a grafting agent for TPV (in the presence of dicumyl peroxide) during the melt mixing. The nanocomposite was intercalated, as evidenced by X-ray diffraction. The tensile modulus of the 5% TPV/organoclay nanocomposite was higher than that of the 20% talc-filled microcomposite. The storage modulus of the nanocomposite was higher than that of the pristine TPV. The most important observation is obtained from dynamic mechanical analysis, which reveals that the glass-transition temperature of the polypropylene phase of the nanocomposite increases (as compared to virgin TPV), whereas the ethylene-propylene-diene monomer phase remains almost the same.

show abstract

Section: Introductionmentioning

confidence: 99%

A new thermoplastic vulcanizate (TPV)/organoclay nanocomposite: Preparation, characterization, and properties

Mishra

Kim

et al. 2004

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

show abstract

“…Polymers intercalated in layered-inorganic compounds such as graphite, 2:1 aluminosilicates, and transition metal halides have recently attracted very strong interest, both as novel composite materials, as well as model systems for nanoscopically confined polymers. Experimental 1,2 and simulation approaches [3][4][5][6][7][8] offer a detailed molecular description of the behavior of these systems, and a very striking picture is emerging for the physics of polymers in nm-scale confinements. These systems self-assemble in highly-ordered intercalated structures, which allow for the preparation of samples with macroscopic quantities of nanoscopicallyconfined polymers.…”

Section: Introductionmentioning

confidence: 99%

Dynamics of poly(ethylene oxide) in nanoscale confinements: A computer simulations perspective

Kuppa

Manias

2003

The Journal of Chemical Physics

View full text Add to dashboard Cite

Molecular Dynamics simulations are used to explore the effect of severe-1 nanometerconfinement on the short-time dynamics of poly͑ethylene oxide͒ ͑PEO͒. Bulk and intercalated systems have been atomistically modeled to comparatively illustrate their differences. In particular, we aim to trace the molecular level mechanisms responsible for the counter intuitive distribution of relaxation times recorded by solid state 2 H NMR for the C-H bond reorientations in confinements. Computer simulations complement the experiments and reveal that factors such as local density inhomogeneities, proximity of Li ϩ , and disorder in the system, combine to determine the PEO segmental dynamics. In contrast with the respective bulk PEO systems, where a clear transition from distinct solid to liquid like dynamics takes place with increasing temperatures, for the nanoscopically confined chains there persists a coexistence of fast and slow segmental relaxations over the same temperature range.

show abstract

“…As an alternative, coarse-grained models have been developed. These lump a number of molecules or mers into a single grain and then compute the performance of PNO, [11][12][13][14]18 polymer blends, or block copolymers. 29,30 With growing frequency, MD simulations are being used to solve practical industrial problems.…”

Section: Introductionmentioning

confidence: 99%

“…In particular, the modulus, hardness, tensile strength, heat deflection temperature, flammability, and barrier properties are likely to be enhanced. 1 The clay dispersion process has been modeled considering the thermodynamics, 2-10 kinetics, [11][12][13][14][15][16][17][18][19][20] and continuum mechanics. 21,22 Unlike conventional composites, polymeric nanocomposites ͑PNC͒ usually contain less than 5 vol % of solid reinforcement.…”

Section: Introductionmentioning

confidence: 99%

Numerical simulation of polymer nanocomposites using self-consistent mean-field model

Kim

Utracki

Kamal

2004

The Journal of Chemical Physics

View full text Add to dashboard Cite

Clay-containing polymeric nanocomposites (PNC) are mixtures of dispersed clay platelets in a polymeric matrix. These materials show enhancement of physical properties, such as modulus, strength, and dimensional stability, as well as a reduction of gas permeability and flammability. The performance is related to the degree of clay dispersion (i.e., intercalation or exfoliation) and the bonding between the clay and the matrix. The main goal of this work has been to map the degree of dispersion as a function of independent variables (viz., magnitude of the interaction parameters, molecular weights, composition, etc.). In this paper, we present the results of the numerical analysis of the equilibrium thermodynamic miscibility using one- and two-dimensional (1D and 2D) models based on the self-consistent mean-field theory. In the limit, the 2D model reproduced the 1D model published results. The adopted 2D model considers the presence of four PNC components: solid clay platelets, low molecular weight intercalant, polymeric matrix, and end-functionalized compatibilizer. The simulations, with realistic values of the binary interaction parameters, were analyzed for potential exfoliation of PNC with a polyolefin as the matrix. The simulation results show that intercalation and exfoliation is expected within limited ranges of the independent variables. The presence of a bare clay surface (e.g., generated by thermal decomposition of intercalant or extraction by molten polymer) has a strong negative effect on the dispersion process. The simulation successfully identified the most influential factors, e.g., optimum ranges of the compatibilizer and the intercalant concentration.

show abstract

Molecular view of polymer flow into a strongly attractive slit

Cited by 29 publications

References 34 publications

A new thermoplastic vulcanizate (TPV)/organoclay nanocomposite: Preparation, characterization, and properties

A new thermoplastic vulcanizate (TPV)/organoclay nanocomposite: Preparation, characterization, and properties

Dynamics of poly(ethylene oxide) in nanoscale confinements: A computer simulations perspective

Numerical simulation of polymer nanocomposites using self-consistent mean-field model

Contact Info

Product

Resources

About