Effects of Filler Surface Modification on Coupling Effects in Halogen-Free Flame-Retardant Cable Compounds — Part 2
To further investigate the thermo-mechanical stability, DMA tests were conducted. Filled samples made of pure EVA (a), pure LLDPE (b), and the 50/50 blend © are shown in Figure 5. The modulus of the pure EVA (a) sample is not significantly affected by the coating of the filler. Only the vinylsilane samples show a decrease in modulus above 20°C, which underlines the theory of reduced interaction. As seen in previous mechanical results, no influence of the MAA-g-EVA coupling agent can be observed. The LLDPE (b) samples show a clear improvement with the use of a coupling agent for all filler surface variants. The thermo-mechanical stability of the sample using uncoated filler is the highest, followed by the aminosilane sample, with vinylsilane being the weakest.