PSI - Issue 82

Lenka Markovičová et al. / Procedia Structural Integrity 82 (2026) 274 – 280 L. Markovičová et al./ Structural Integrity Procedia 00 (2026) 000–000

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right was observed. This indicates that with increasing glass fiber content, the material transitions to a region with a lower molecular weight, where the polymer chains are shorter or less branched. Furthermore, the effect of UV radiation on the rheological characteristics of the individual layers of composites with 10%, 20%, and 30% glass fiber content was investigated. For the composite samples with 10% and 20% glass fiber content (Figs. 4, 5), material degradation was observed — a decrease in molecular weight occurred, along with a shift toward a broader molecular weight distribution region (the COP shifted further to the right and downward). Samples exposed to UV radiation also showed lower viscosity values compared to the samples not exposed to UV radiation.

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