Recent technical developments in resin formulation and the design of pre-forms has allowed the beverage industry to use clarified PP in the same way as PET.
This means that bottlers can use the material for the injection of pre-forms, which are then stretched and blown to form low-cost bottles, with perfect transparence, and able to be hot fill packaged.
According to Milliken, one of the companies behind the development of PP (polypropylene), this marks a significant breakthrough. PP has historically not had good barrier properties to oxygen or to CO2, which is why neither the carbonated beverages market, nor the market for food highly sensitive to oxygen, has been targeted in the past .
However, Milliken claims that its high temperature resistance allows for hot fill packaging, which opens up a wide range of possibilities for the food, beverage and dairy industries. The firm argues that even for cold fill packaging, PP offers a competitive advantage compared to the alternatives available in the market.
This is because its moisture and aroma barrier properties are excellent, making it highly recommended for packaging spices, powdered food, instant coffee, cereals or capsules.
As a result, Milliken believes that the misapprehension that clarified PP does not have the same productivity as PET should be dismissed. Packaging manufacturer Sidel has carried out several successful tests using its 2+SBO series equipment.
The contributions of this work have already had results in Brazil. Thanks to a partnership between Braskem, as PP supplier with its new Braskem Prisma 3400 resin, Milliken, as additives supplier, and Sidel, as blowing equipment producer; Packpet (transformer) has succeeded in the development of a clarified PP bottle for Hot Fill packaging, with excellent mechanical resistance and transparency, as well as a competitive cost.
The company has therefore been able to meet the requirements of its customers. Milliken claims that this shows that PP represents an important alternative for beverage producers, who can now reduce the use of preservatives in their formulas due to the hot fill packaging of their products and meet the market demand for healthier beverages.
Another factor for beverage firms is cost. High energy costs have forced raw material prices up, and resin producers have been able to pass rising costs because of global demand - largely from China - and are in a position to divert supply if a packaging manufacturer refuses to pay higher tariffs.
However according to the Plastics Exchange, PP prices have accelerated their descent, with spot prices falling sharply in March. This development is contrary to PP producer expectations, who actually planned to further raise prices.