24/06/2005 - Controller General of Patents, Designs, and Trade Marks

(21) Application No. 1066/DEL/2003 A (22) Date of filing of Application: 29/08/2003
(54) Title of the invention: “COEXTRUSION TIE BASED ON COGRAFTED METALLOCENE
POLYETHYLENE AND LLDPE, ON SBS AND ON PE.”
(51) International Classification 7 : C 08L 43/00
(30) Priority Data :
(31) Document No.: 02.11438
(32) Date : 16/09/2002
(33) Name of convention country : FRANCE
(66) Filed U/s 5(2) : NIL
(61) Patent of addition to application No. : NA
(62) Filed on : NA
(63) Divisional to Application No. :NIL
(64) Filed on : NA
Total No. of Pages:17
(57) Abstract:
(71) Name of the applicant:
ATOFINA.
Address of the Applicant:
4-8, Cours Michelet, F-92800 Puteaux,
France.
(72) Name of the Inventor:
PRADEL JEAN-LAURENT
PASCAL JEROME, LE BEURON
ROBERT PATRICE.
The present invention relates to a coextrusion tie comprising:
- 10 to 35 weight% of a polymer (A) itself composed of a blend of 80 to 20 weight% of a
metallocene polyethylene (A1) with a density of between 0.865 and 0.915 and of 20 to 80
weight% of a non-metallocene LLDPE polyethylene (A2), the blend of polymers (A1) and
(A2) being cografted by an unsaturated carboxylic acid or its derivative, the content of
which in the said blend is between 30 and 100 000 ppm;
- 40 to 60 weight% of a styrene/butadiene/styrene block copolymer (B) with 50 to 90 mol%
of styrene;
- 20 to 35 weight% of PE (C);
the total making 100%, the blend of (A), (B) and (C) being such that the MFI or melt flow
index (ASTM D 1238, 190 o C, 2.16 kg) is between 0.1 and 10 g/10 min.
The present invention also relates to a multiplayer structure comprising a layer of tie according
to the invention and to the objects comprising such a structure.
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