Key Factors of Mechanical Strength and Toughness in Oriented Poly(l-lactic acid) Monofilaments for a Bioresorbable Self-Expanding Stent

The investigation of the strength and toughness of poly(l-lactic acid) (PLLA) monofilaments is essential as the fundamental element of a biodegradable braided stent. However, the determining factor remains poorly addressed with respect to influencing the mechanical behavior of PLLA monofilaments. In...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 38(2022), 44 vom: 08. Nov., Seite 13477-13487
1. Verfasser: Wang, Bin (VerfasserIn)
Weitere Verfasser: Liu, Muqing, Liu, Jinbo, Tian, Yuan, Liu, Wentao, Wu, Gensheng, Cheng, Jie, Zhang, Yi, Zhao, Gutian, Ni, Zhonghua
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2022
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't poly(lactide) 459TN2L5F5 Polyesters
Beschreibung
Zusammenfassung:The investigation of the strength and toughness of poly(l-lactic acid) (PLLA) monofilaments is essential as the fundamental element of a biodegradable braided stent. However, the determining factor remains poorly addressed with respect to influencing the mechanical behavior of PLLA monofilaments. In this work, the electron beam (EB) with different radiation doses was utilized to sterilize PLLA monofilaments. Properties of the monofilaments, including the breaking strength, elongation at break, molecular weight, orientation, and microstructure of the fracture, were characterized. Results showed that a random chain scission of PLLA resulting from EB during this process could cause the decrease in molecular weight, which led to the decline in breaking strength. Meanwhile, the irradiated monofilaments were found to have almost the same elongation at break below a dose of 30 kGy and declined by 71.41% up to a dose of 48 kGy. It was also found that the ductile fracture connection of the monofilament translated to the brittle fracture by comparing the microstructure without and with sterilization. These phenomena could originate from the destruction of the long molecular chains connecting the crystal plates into shorter ones by radiation. PLLA monofilaments with 0, 30, and 48 kGy were used to braid carotid stents. Compared with a carotid Wallstent, the PLLA stent can better provide radial supporting to the carotid lesion. This study provides preliminary experimental references to evaluate and predict the mechanical performance of PLLA braided stents
Beschreibung:Date Completed 09.11.2022
Date Revised 15.12.2022
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/acs.langmuir.2c01972