Identification and quantification of the crystalline structures of poly(vinylidene fluoride) sutures by wide-angle X-ray scattering and differential scanning calorimetry

✍ Scribed by Laroche, Ga�tan ;Lafrance, Claude-Paul ;Prud'homme, Robert E. ;Guidoin, Robert

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 120 KB
• Volume: 39
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/(sici)1097-4636(199802)39:2<184::aid-jbm3>3.0.co;2-l

✦ Synopsis

The outstanding biocompatibility of the polyvinylidene fluoride (PVDF) monofilament suture together with other desirable characteristics, such as ease of handling and resistance to biodegradation, makes it an attractive alternative monofilament suture material for cardiovascular surgery. However, to achieve a high performance suture, the polymeric raw material must be exposed to different treatments, which lead to different degrees and types of crystallization. Since these crystalline modifications deeply influence the mechanical characteristics and the biostability of the sutures, the authors hereby propose a method of quantifying the different structures of PVDF using wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The commercial devices are achieved by coloring and processing the polymeric raw material. The white and unprocessed 4-0 unswaged suture presents 19% of the ␣ phase, 38% of the ␤ structure, and no ␥ form. Coloration increases the amount of the ␤ phase by 5-9% at the expense of the ␣ phase. On the other hand, processing the fibers lead to the conversion of some of the amorphous phase to the ␥ structure, the importance of which is 6-7%. Finally, tensile measurements performed on the different PVDF fibers clearly proves that their mechanical characteristics depend on the presence of these crystalline forms in the polymeric structure of PVDF.