On the micromechanisms of plastic deformation in semicrystalline polymers

Petermann, J.; Ebener, H.

doi:10.1080/00222349908248142

Cited by 9 publications

(5 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[ 60 ] But in the yield point ( σ Y ≈ 4.7 MPa, γ Y ≈ 10%), the inability to transfer the stress beyond the crystallite's boundaries led to lamellae splitting and fragmentation into blocks, giving way to plastic deformation and necking of specimen tests. [ 61–63 ] The highlight of PGl stress‐strain curves was precisely that, the plastic deformation occurring from 10% to 300%, when neck propagation and easy plastic flow of the specimen tests were noticed. Throughout this region, the great mobility of the amorphous phase was recovered owing to lamellae fragmentation and crystal slipping after the yield point, which allowed the orientation of the amorphous phase in the direction of the stress with relatively low stress requirement.…”

Section: Resultsmentioning

confidence: 96%

Synthesis of Functionalized Triblock Copolyesters Derived from Lactic Acid and Macrolactones for Bone Tissue Regeneration

Cutillas

Sanz-Serrano

Oh³

et al. 2023

Macromolecular Bioscience

View full text Add to dashboard Cite

Synthetic and functional grafts are a great alternative to conventional grafts. They can provide a physical support and the precise signaling for cells to heal damaged tissues. In this study, a novel RGD peptide end‐functionalized poly(ethylene glycol)‐b‐poly(lactic acid)‐b‐poly(globalide)‐b‐poly(lactic acid)‐b‐poly(ethylene glycol) (RGD‐PEG‐PLA‐PGl‐PLA‐PEG‐RGD) is synthetized and used to prepare functional scaffolds. The PGl inner block is obtained by enzymatic ring‐opening polymerization of globalide. The outer PLA blocks are obtained by ring‐opening polymerization of both, l‐lactide or a racemic mixture, initiated by the α‐ω‐telechelic polymacrolactone. The presence of PGl inner block enhances the toughness of PLA‐based scaffolds, with an increase of the elongation at break up to 300% when the longer block of PGl is used. PLA‐PGl‐PLA copolymer is coupled with α‐ω‐telechelic PEG diacids by esterification reaction. PEGylation provides hydrophilic scaffolds as the contact angle is reduced from 114° to 74.8°. That difference improves the contact between the scaffolds and the culture media. Moreover, the scaffolds are functionalized with RGD peptides at the surface significantly enhancing the adhesion and proliferation of bone marrow‐derived primary mesenchymal stem cells and MC3T3‐E1 cell lines in vitro. These results place this multifunctional polymer as a great candidate for the preparation of temporary grafts.

show abstract

Section: Resultsmentioning

confidence: 96%

Synthesis of Functionalized Triblock Copolyesters Derived from Lactic Acid and Macrolactones for Bone Tissue Regeneration

Cutillas

Sanz-Serrano

Oh³

et al. 2023

Macromolecular Bioscience

View full text Add to dashboard Cite

show abstract

“…By comparing the WAXS patterns at 50% strain with simulated 2D WAXS patterns from literature, we could assume that during applied tensile stress the (120) plane, which lies perpendicular to the c-axis, is meridional aligned to the tensile direction. Therefore, the c-axis is becoming aligned in tensile direction (Adams et al, 1986;Petermann and Ebener, 1999;Zhu et al, 2000;Lai et al, 2012). Due to the crystalline structure of PEO with an angle of 90 • between the (120) plane and the c-axis, this correlation can be used to make predictions about the crystalline structure by examining the peak broadening and position during applied tensile stress.…”

Section: Discussionmentioning

confidence: 99%

“…The process of deformation for bulk semi-crystalline polymers has been described by different studies (Adams et al, 1986;Petermann and Ebener, 1999;Zhu et al, 2000;Liu et al, 2006). The deformation in such materials during applied tensile load can be characterized by an initial elongation of the amorphous phase, followed by a shearing and tilting of the lamellar folded chains.…”

Section: Discussionmentioning

confidence: 99%

“…The deformation in such materials during applied tensile load can be characterized by an initial elongation of the amorphous phase, followed by a shearing and tilting of the lamellar folded chains. Afterwards, block crystals are pulled out of the lamellae, which is referred to as "block slip" mechanism and those blocks become further aligned along the tensile axis (Adams et al, 1986;Petermann and Ebener, 1999;Lai et al, 2012).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Correlative Analysis of Specific Compatibilization in Composites by Coupling in situ X-Ray Scattering and Mechanical Tensile Testing

et al. 2020

View full text Add to dashboard Cite

In this study, a bio-inspired hybrid material is investigated by in situ X-ray scattering experiments in combination with mechanical tensile testing. The material is composed of nanometer-sized spherical magnesium fluoride particles which are linked via material-specific peptide poly(ethylene glycol)-PEG conjugates to a semi-crystalline poly(ethylene oxide) PEO matrix. Mechanically relevant changes in crystal size and orientation in the PEO matrix are followed by wide angle X-ray scattering during the application of tensile stress. The amorphous phase of PEO is stabilized by the surfaceengineered MgF 2 nanoparticles, leading to increased Young's modulus and tensile strength. Furthermore, small angle X-ray scattering experiments allowed the identification of a layer on the MgF 2 particle surfaces, which increases in thickness with the conjugate amount and leads to suppression of the agglomeration of MgF 2 nanoparticles. In conclusion, the use of selected peptide-PEG conjugates tailored to link MgF 2 particles to a PEO matrix successfully mimics the biological principle of interface polymers and suggests new directions for material fabrication for bio-applications.

show abstract

“…The spatial arrangement and mechanical stability of crystalline regions are important factors in determining the mechanical properties of the material . Previous micromechanical studies focused on averaged crystal orientation, − crystallinity during straining, , and the study of crazing, , which is a common failure mechanism of these materials. Here, we report on unexpected locally auxetic behavior in elastomeric polypropylene (ePP), a semicrystalline polymer with a low degree of crystallinity .…”

mentioning

confidence: 99%

Locally Auxetic Behavior of Elastomeric Polypropylene on the 100 nm Length Scale

Franke

Magerle

2011

ACS Nano

View full text Add to dashboard Cite

We observe unexpected locally auxetic behavior in elastomeric polypropylene, a semicrystalline polymer with a natural microstructure and a low degree of crystallinity. Our series of scanning force microscopy images show the nanomechanical deformation processes that occur upon stretching a thin film of elastomeric polypropylene. Upon uniaxial stretching, the angle between epitaxially grown lamella branches remains constant and the lamellae elongate, resulting in locally auxetic behavior (negative Poisson's ratio) on the 100-nanometer scale. This mechanism causing auxetic behavior, which was previously proposed on the basis of geometric arguments, appears to be an intrinsic property of certain semicrystalline polymers.

show abstract

On the micromechanisms of plastic deformation in semicrystalline polymers

Cited by 9 publications

References 18 publications

Synthesis of Functionalized Triblock Copolyesters Derived from Lactic Acid and Macrolactones for Bone Tissue Regeneration

Synthesis of Functionalized Triblock Copolyesters Derived from Lactic Acid and Macrolactones for Bone Tissue Regeneration

Correlative Analysis of Specific Compatibilization in Composites by Coupling in situ X-Ray Scattering and Mechanical Tensile Testing

Locally Auxetic Behavior of Elastomeric Polypropylene on the 100 nm Length Scale

Contact Info

Product

Resources

About