The Indian extrusion processing sector is now becoming familiar with using mLLDPE resins in producing mono and multi-layer structures for food and industrial packaging.

In Europe and USA, reputed masterbatch suppliers servicing the industry have focused on developing additive concentrates in mLLDPE as carrier, in place of conventional LDPE or LLDPE. This has resulted in minimizing any loss of strength, including dart and Izod impact and tear resistance - besides retaining the excellent optical properties inherent in such film resins.
Metallocene film resins are morphologically different because they are more uniform in structure. This tends to retard migration of the additives to the surface. Formulating these additives so that they can migrate better to the surface is the answer. Optimized concentrates with higher than usual 'active ingredient loadings' overcome the migration problem.

One of the usual problems encountered with the low softening point or heat seal temperature of mLLDPE and some other low density high performance resins is that they tend to have a tacky surface. Their COF value is high and as a result, they adhere to other films as well as to themselves and to metal surfaces of the production equipment. Their aim is to decrease the COF, reducing the sticking tendency and this can be done by utilizing high 'active ingredient' masterbatches based on mLLDPE as carrier resin. The masterbatch is strongly suggested for use in multi-layer film applications where mLLDPE or a plastomer is used as the skin or heat seal layer. Examples include fresh produce packaging and meat wraps that require very high gloss, low haze and very high clarity.

(Courtesy - Plastics Technology)