Studying the impact of synthetic silica and cross-linked polymethyl methacrylate as anti-blocking agents on the physical properties of electric cables

One of the major problems associated with the production process of cables is the tight adhesion between the insulation and jacket (blocking), which is resulted from electrostatic and Van der Waals interactions between the two polymer layers. It makes them difficult to separate without damaging the insulation. As a conventional approach, a talc layer is applied within the insulation and jacket interface to prevent the blocking between the jacket and insulation. However, maintaining a uniform talc layer is difficult, and the uneven distribution of talc particles produces a non-smooth surface. Therefore, the conventional talc layer method has limited efficiency in reducing the bocking. In this study, a surface modification was done for both the insulation and jacket using synthetic silica and crosslinked polymethyl methacrylate (PMMA). This study evaluated the effect of these two additives on other physical properties, including heat stability, insulation resistance, tensile strength, elongation at break, and pressure stability. This study reveals that the application of synthetic silica has successfully reduced the blocking between insulation and jacket and favorably contributed to increasing insulation resistance. The optimum levels of anti-blocking agents to be used in the insulation and jacket compound have also been estimated by this investigation.