Relating fracture energy to entanglements at partially miscible polymer interfaces

Gorga, Russell E.; Narasimhan, Balaji

doi:10.1002/polb.10285

Cited by 18 publications

(7 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This communication focuses on the effect of polydispersity on the phase behavior of polymer blends. It is well known that the phase behavior affects interfacial characteristics, such as the interfacial width30 and fracture energy30–32. Therefore, these results are relevant to studies on the effect of polydispersity on interfacial behavior.…”

Section: Resultsmentioning

confidence: 95%

Effect of Polydispersity on the Phase Behavior of Polymer Blends

Seifert

Thiyagarajan

et al. 2005

Macromol. Rapid Commun.

Self Cite

View full text Add to dashboard Cite

Summary: The effect of polydispersity on polymer blend phase behavior is studied by in situ small‐angle X‐ray scattering. In a polydisperse polyethylene (PE)/isotactic poly(propylene) (iPP) blend, the enthalpic portion of the interaction parameter is greater than that of a corresponding blend with lower polydispersity. This is attributed to the presence of long chains, which provide a higher interaction energy and packing constraint, reducing the system miscibility. As expected, the radius of gyration is higher in the system with higher polydispersity.

show abstract

Section: Resultsmentioning

confidence: 95%

Effect of Polydispersity on the Phase Behavior of Polymer Blends

Seifert

Thiyagarajan

et al. 2005

Macromol. Rapid Commun.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Figure 10 plots the interfacial width as a function of the fracture energy. Previous work1, 9, 11, 32 has shown that a linear relationship exists between the fracture energy and the square of the interfacial width for amorphous polymer interfaces. Our data indicate that semicrystalline polymer interfaces do not show the same quantitative relationship between G c and w but clearly do show that G c increases with w .…”

Section: Resultsmentioning

confidence: 90%

Interfacial adhesion mechanisms in incompatible semicrystalline polymer systems

Laabs

Narasimhan

2004

J Polym Sci B Polym Phys

Self Cite

View full text Add to dashboard Cite

The mechanism of adhesion at semicrystalline polymer interfaces between isotactic polypropylene (iPP) and linear low-density polyethylene (PE) was studied with transmission electron microscopy (TEM) and an asymmetric-double-cantilever-beam test. From the TEM images, both the interfacial width and the lamellar thickness of the polymers were extracted. During annealing, the interfacial width increased with the annealing temperature, and this indicated the accumulation of amorphous polymers at the interface. The interfacial strength, determined from the critical fracture energy (G c ), also increased with the annealing temperature and reached a maximum above the melting temperatures of iPP and PE, whereas the smallest G c value was obtained below the melting temperatures of the two materials. A mechanism of interfacial strengthening was proposed accounting for the competition between the interdiffusion of PE and crystallization of iPP. As the annealing temperature increased, the rates of PE diffusion and iPP crystallization increased. Although the crystallization of iPP hindered the interdiffusion of PE, both the interfacial width and the fracture energy increased with the temperature, and this indicated that PE interdiffusion dominated iPP crystallization. Below the critical temperature, the fracture surfaces of both iPP and PE were smooth, and chain pullout dominated the fracture mechanism. Above the critical temperature, iPP crystallization still hindered the interdiffusion, and crazes could be seen on the iPP side. Above the melting temperatures of the two materials, ruptured surfaces could also be seen on the PE side, and crazing was the fracture mechanism.

show abstract

“…For polymers, the diffusion process can be interpreted as the entanglements of polymer chains from different materials. [17][18][19] By controlling the annealing temperature and time, different interfacial thicknesses in the range of 5 to 50 nm can be generated. The temperature range of interest, where significant variation in the interfacial width is expected, falls between the melting temperatures of iPP and PE.…”

Section: Methodsmentioning

confidence: 99%

Measurements of diffusion thickness at polymer interfaces by nanoindentation: A numerically calibrated experimental approach

Yang

Bastawros

et al. 2009

J. Mater. Res.

Self Cite

View full text Add to dashboard Cite

The interfacial fracture toughness and the adhesion strength of two dissimilar materials are governed by the diffusion interfacial thickness and its mechanical characteristics. A new testing methodology is implemented here to estimate the actual interfacial thickness from a series of nanoindentations across the interface, under the same applied load, with tip radius and indentation depth many times larger than the interface thickness. The bimaterial system used is a semicrystalline polymer interface of isotactic polypropylene and linear low-density polyethylene. The laminate is prepared under a range of diffusion temperature to yield diffusion interfaces of 0 to 50 nm. A numerical relationship is developed using two-dimensional (2D) finite element simulation to correlate the true interfacial thickness, measured by transmission electron microscopy, with the experimentally estimated apparent interfacial thickness, derived from the transition domain of a series of indents across the interface. A range of material-pairs property combinations are examined for Young's modulus ratio E 1 /E 2 = 1 to 3, yield strength ratio s Y1 /s Y2 = 1 to 2.5, and interfacial thickness of 0 to 100 nm. The proposed methodology and the numerically calibrated relationship are in good agreement with the true interfacial thickness.

show abstract

Relating fracture energy to entanglements at partially miscible polymer interfaces

Cited by 18 publications

References 41 publications

Effect of Polydispersity on the Phase Behavior of Polymer Blends

Effect of Polydispersity on the Phase Behavior of Polymer Blends

Interfacial adhesion mechanisms in incompatible semicrystalline polymer systems

Measurements of diffusion thickness at polymer interfaces by nanoindentation: A numerically calibrated experimental approach

Contact Info

Product

Resources

About