POLYETHYLENE FILM AND METHOD OF MANUFACTURING THEREOF Russian patent published in 2014 - IPC C08J5/18 B29C43/00 C08L23/04 B29C55/12 

FIELD: chemistry.

SUBSTANCE: claimed invention relates to a solvent-free polyethylene film, which can be applied, for instance, in membranes, packing, and ballistics. The polyethylene film has a ratio between the strength in the first direction in the film plane and the strength in the second direction in the film plane, perpendicular to the first direction, in the range of 0.1-10:1. The strength in, at least, one direction in the film plane constitutes not less than 0.2 GPa. The weight-average molecular weight of polyethylene constitutes not less than 500000 g/mol, and a value of ratio Mw/Mn does not exceed 6. The method of the said film manufacturing is performed by processing an initial polymer of polyethylene UHMWPE with the weight-average molecular weight of not less than 500000 g/mol by elastic shear modulus, determined immediately after melting at 160°C, not higher than 1.4 MPa, and a value of Mw/Mn ratio not higher than 6. Processing is carried out by pressing in the absence of a solvent. A stage of extraction is performed in such conditions that the temperature of the polymer film half-product does not exceed the temperature of the polymer melting at any time moment. During extraction the force is applied to the polymer film half-product in the first direction and in the second direction, which is perpendicular to the first direction.

EFFECT: film, possessing high strength more than in one direction in the film plane, is obtained.

15 cl, 2 tbl