Introduction Recycling and Optical Properties

The optical properties of plastic items (such as haze, transparency or clarity and transmittance) are key issues in packaging applications, especially films, since they allow the consumer to see what is contained within the package. Hence, optical properties are important features in the marketability of a particular product and control of these properties is therefore required whether the film is utilised for food packaging, pallet wrap or other related applications [1,2]. 

The market for polyolefin film is enormous and continually growing, with a major component of that market used for packaging, and the recycling of these materials 

The recycling of polymers has become a necessary part of the development of a sustainable society. The recycling of low price bulk polymers, the group to which the polyolefins belong, is seen by many as a waste of time and resources when they can be easily channelled into the energy recovery process [3]. 

as an example, 10 million tonnes of postconsumer plastic waste is buried in landfill sites every year across Europe. The quantity of postconsumer plastic which is recycled or recovered has increased every year since 1990. However, the rates still lag well behind other products such as newspaper which stands at 80%. With recent restrictions on landfill and increased demand for sustainability, there is a huge amount of work to be done to achieve parity and there are substantial business opportunities available. 

The large-scale use of recycled plastics in the manufacturing of second-market plastic products is still hindered by a wide range of barriers. The image of recycled plastics, in comparison to the equivalent virgin polymers, is distorted by several factors [4], which may lead to the manufacturers mistrust of the performance of the recycled 

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