Calcined Kaolin in Film Applications
When formulated into compounds Imerys calcined kaolin improves the thermal properties of agricultural films, giving the potential to reduce heating costs, reduce the planting to cropping time and increase the lnegth of the growing season. In film that requires antiblock additive, calcined kaolin offers an ideal and cost effective balance of antiblock, haze and clarity performance.
When calcined kaolin PoleStar 200R is compounded into Polyethylene thermal barrier film the infrared spectrum of the film is modified. Tests prove that films containing PoleStar 200R absorb more infrared radiation than films compoiunded with talc, silica or calcium carbonate. This means that heat is retained inside polytunnels for longer, reducing the heating required, shortening the cycle time between planting and cropping and lengthening the growing season. All are benefits to farmers who are always looking for ways to become more efficient and productive. The effect of the calcined kaolin on the mechanical properties is minimal.
Polyolefin films contain several additives to improve and modify their technical performance, stability and handling, such as UV stabilisers to prolong film life, process aids to assist film blowing and antiblocking additives to prevent the film sticking to itself. PoleStar 200R is used as an antiblock additive which when used at around 2500 ppm gives a good balance of antiblocking performance and film haze and clarity, when compared to other antiblocking additives such as talc and diatomaceous earth.
Imerys have a portfolio of high performance antiblocking minerals which have ultrafine particle sizes. These are used in extremely thin extruded polyester films. Control and consistency of particle size is essential and this is achieved by using the mineral processing skills developed over many years.
Customers wishing to have materials made to their own specification should consider our Toll Processing service.
Product Related Literature
For more detailed information on all film applications contact our Technical manager