Antistatic modification of polypropylene by incorporating Tween/modified Tween

Tween, one type of non-ionic surfactants, was used as inner antistatic agent of polypropylene (PP) and the antistatic performance of PP/Tween sheets were evaluated by surface resistivities (ρs) and water contact angles. The influence factors including hydrophile–lipophile balance (HLB) of Tween, addition amount, process conditions and atmospheric humidity were investigated in detail and the results showed Tween 40 with HLB at 15.7 provided PP an optimum antistatic effect with surface resistivity of 1010 Ω/sq, water contact angle of 57°, and surface energy of 49.5 mN/m. The ρs of PP/Tween sheets declined approximately 1 order of magnitude with 10% increasing of relative humidity. In order to improve the washing endurance of antistatic PP, a combination of T40 and cationic PP (CPP) were blended with PP and PP/CPP/T40 sheets revealed improved washing durability, with ρs below 1011 Ω/sq after ultrasound washing. In addition, T40 with double bonds was synthesized and UV crosslinking of modified T40 on PP surface also presented definite effects on water resistance.