Dataset Information

Structural Evolution and Toughening Mechanism of ?-Transcrystallinity of Polypropylene Induced by the Two-Dimensional Layered Interface during Uniaxial Stretching.

ABSTRACT: The structure and morphology of ?-crystals of isotactic polypropylene (iPP) are of great significance because ?-crystals can improve the toughness and ductility of iPP. Toughening of ?-spherulites, which was ascribed to phase transformation, has been extensively investigated. However, the toughening mechanism of other ?-crystals with special structures and morphologies is not clear. In this study, ?-transcrystallinity (?-TC), which showed a greater toughening effect than that of ?-spherulite, was constructed through microlayered coextrusion. During uniaxial stretching, ?-TC preferred to transform into an ?-crystal, whereas ?-spherulite preferred to transform to a smectic mesophase. The transformation degree of ?-TC was much higher than that of ?-spherulite. More importantly, the lamellar fragments from ?-TC gradually rearranged along the stretching direction, accompanied by continuous absorption of energy. The special ?-? phase transformation, high transformation rate, and rearrangement of lamellar fragments led to the highly improved toughness of the layered samples.

SUBMITTER: Yang S

PROVIDER: S-EPMC6641441 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Structural Evolution and Toughening Mechanism of β-Transcrystallinity of Polypropylene Induced by the Two-Dimensional Layered Interface during Uniaxial Stretching.

Yang Shuo S Yu Huaning H Li Jiang J Guo Shaoyun S Wu Hong H Shen Jiabin J Xiong Ying Y Chen Rong R

ACS omega 20170307 3

The structure and morphology of β-crystals of isotactic polypropylene (iPP) are of great significance because β-crystals can improve the toughness and ductility of iPP. Toughening of β-spherulites, which was ascribed to phase transformation, has been extensively investigated. However, the toughening mechanism of other β-crystals with special structures and morphologies is not clear. In this study, β-transcrystallinity (β-TC), which showed a greater toughening effect than that of β-spherulite, wa ...[more]

PMID: 31457473

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Dataset Information

Structural Evolution and Toughening Mechanism of ?-Transcrystallinity of Polypropylene Induced by the Two-Dimensional Layered Interface during Uniaxial Stretching.

Publications

Structural Evolution and Toughening Mechanism of β-Transcrystallinity of Polypropylene Induced by the Two-Dimensional Layered Interface during Uniaxial Stretching.

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