Thermal and mechanical behavior of amorphous and semi-crystalline poly(vinylidene fluoride)/poly(methyl methacrylate) blends

• Published in: Macromolecular symposia. Vol. 198; no. 1; pp. 103 - 116
• Main Authors: Jarray, Jlidi, Larbi, Fadhel Ben Cheikh, Vanhulle, Faustine, Dubault, André, Halary, Jean Louis
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.08.2003; WILEY‐VCH Verlag
• Subjects: Blends; Degree of crystallinity; Fluorides; Glass transition; mechanical relaxation; Plastic deformation; poly(methyl methacrylate); poly(vinylidene fluoride); Polymer blends; Polymethyl methacrylates; Polyvinylidene fluorides
• ISSN: 1022-1360; 1521-3900
• DOI: 10.1002/masy.200350810

Various PVDF/PMMA (poly(vinylidene fluoride)/poly(methyl methacrylate)) blends were selected for mechanical testing in compression. At low PVDF content (less than 50/50 w/w), the blends remain amorphous and PVDF and PMMA are fully miscible. In PVDF‐richer blends, PVDF crystallizes in part, leading to a PMMA‐enriched homogeneous amorphous phase. In this study, the degree of crystallinity was set at equilibrium by appropriate annealing of the samples before testing. Mechanical analysis was focused on the low deformation range, and especially on the yield region. Depending on the test temperature and blend composition, three types of response were identified, depending on whether plastic deformation is influenced: 1) by the PMMA secondary relaxation motions, 2) by the PVDF/PMMA glass transition motions, or 3) by the crystallite‐constrained PVDF chains.