Study On Preparation And Properties Of PE/Tourmaline Composite Film

Polyethylence film has the most widely use in the field of plastic film. With the quickly improvement of people’s living standard,people put forward higher request on the function of the composite films.Using tourmaline as fill,there is a wide application prospect to prepare PE/tourmaline composite films.In the experiment,we modify the tourmaline with PVA,PAA and aluminium stearate. Then we test the activated index,infrared spectrum and sedimentation time of modified tourmaline.Ensure the best modification conditions of the three kinds of modified agents to prepare the composite films.Second,we prepare LDPE/tourmaline composite film with melting blend and blow molding process.Test the rheological properties,mechanical properties,air permeability, and moisture penetrability of the composite films, and use the DSC informations to study the crystallization kinetics of composite films.The results show that:PVA is one of the non-ionic surface active agent,and tourmaline modified by PVA belongs to physical adsorption.When the dosage of PVA is1.5%, the tourmaline which is modified could have the best activation degrees and the longest sedmentation time.PAA and aluminium stearate all belong to anionic modifers,and the tourmaline modified by them pertains to chemical absorption.When the dosage of PAA is1.0%or the dosage of aluminium stearate is1.5%,the tourmaline which is modified by them can aslo reach the activation degrees and the longest sedmentation time.And the tourmaline is modified best by now.The increase of the tourmaline modified by three kinds of modified agents has not too big effect to the melting temperature and the crytallization temperature of the composite films.But the crystallinity of the composite films all have the trend:first up,then down. When they reach the highest crytallinity,the dosage of the tourmaline which is modified by1.5%PVA is6%or so.The dosage of the tourmaline which is modified by1.0%PAA is6%or so. And the dosage of the tourmaline which is modified by1.5%aluminium strearate is5%or so.At the same time,the spherocrystals of LDPE composite films grow in the number with the addition of modified tourmaline.The increase of the modified tourmaline makes the tensile strength, tear strength and the elongation at break of the composite films all have the trend which is first up and then down.When the composite films achieve the best mechanical performances, the dosage of the tourmaline which is modified by1.5%PVA is6%or so.The dosage of the tourmaline which is modified by1.0%PAA is6%or so. And the dosage of the tourmaline which is modified by1.5%aluminium strearate is5%or so.The increase of the modified tourmaline makes the viscosity of the composite films improve a little, but the impact is not too big. And with the increase of shear rate, the viscosity of the composite films decreases.It belongs to the typical false fluid rheological characteristic.The increase of the content of tourmaline modified by the three modifiers can make the Oxygen through rate and WVTR of the composite films increase obviously. The air permeability and the wate vapor permeability of composite films can significantly improve.