Unvulcanized Rubber Tape Made from Natural Rubber and Synthetic Polyisoprene Modified with Rosin as a Tackifier

Abstract

This presented work was to study mechanical and tack properties of unvulcanized rubber tapes made from STR 20 and IR 2200 with various amount of carbon black and rosin as reinforcing agent and tackifier, respectively. Mixing process of solid rubbers and all chemicals was carried out by two roll mill machine. All rubber compounds were subjected to increasing the stickiness by aging under hot air at 150°C for 3 hours. From the experiment, green strength of the sticky rubber tape mixed with carbon black and rosin showed higher than that of the commercial rubber tape. The formulation exhibited the highest tensile stress at 400% strain is STR 20 mixed with 15 and 5 phr of carbon black and rosin, respectively. Mooney viscosity of the rubber tape made from STR 20 and IR 2200 was also reduced with the higher content of rosin. Although Mooney viscosity of the adhesive rubber tape normally decreased after heating under hot air, its tack property investigeted by rolling ball test on the surface predominantly became increased. Moreover, Mooney viscosity of the rubber tape made from IR 2200 would be remarkably enhanced by blending with only 20% of STR 20.