PSI - Issue 40

S.N. Danilova et al. / Procedia Structural Integrity 40 (2022) 118–123 S.N. Danilova, A.A. Dyakonov, A.P. Vasilev, A.A. Okhlopkova / Structural Integrity Procedia 00 (2022) 000 – 000

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Based on Fig. 2, it is possible to say that spherulites of the original UHMWPE are weakly bound with each other, which is noted in a considerable wash-off of the matrix on the edges of spherulites. Introduction of BF contributes to formation of a denser packing of structural elements, which confirms gaining in strength of the composites. As this takes place, it can be clearly seen that the composites, together with the components mechanically co-activated for 20 minutes, are characterized by a smaller size of structural elements, which confirms the formation of fine spherulitic structure. In order to assess the influence of the modification method on the adhesive interaction between UHMWPE and BF, points of PCM rupture at the phase boundary were studied.

Fig. 3. Microphotographs of the rupture points of the PCM based on UHMWPE filled with 2% BF: a – BF (х1000); b – co-activation with BF for 2 minutes; c – co-activation with BF f or 20 minutes (х10000) .

Based on Fig. 3 b and c, it is possible to say that when mechanical treatment is applied, microcracks develop on the surface of the fibers, and the polymer matrix, penetrating into these cracks, gets bound by means of «threads», formed from the macromolecules. Formation of threads on the microcracks accounts for retaining of the material elasticity when tension is applied.