THE EFFECT OF OZONE AGEING ON THE CHEMICAL, PHYSICAL AND BARRIER PROPERTIES OF PACKAGING FILMS

摘要

The effect of ozone (O3) on films of linear low density polyethylene material containing UV additive (LLDPE-UV) and without UV additive (LLDPE-non-UV) have been investigated for the change in chemical, mechanical and barrier properties by exposing in O3 for a long term. The LLDPE-UV material which was exposed up to 312hrs in O3 shows good resistance by causing less formation of oxygen-containing functional group having carbonyl index (CI) of 0.34 vis' a vis' LLDPE-non-UV shows drastic changes in the chemical structure resulting in 2.68 of carbonyl index. The ozone resistance of LLDPE-UV film is further substantiated by improvement in tensile strength property retention time over LLDPE- non-UV films by 137%. The barrier property like water vapor transmission rate was decreased by 23% and 18% upon ageing in O3 medium for the LLDPE-non-UV and LLDPE-UV films respectively.