Extrusion blown molded bottles with high stiffness and transparency
AssigneeBorealis AG
InventorsKlaus Bernreitner, Mari Kylmälä, Manfred Kirchberger, Hansjörg Pramer
Life of this patent
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Abstract
A polypropylene composition comprising a random propylene copolymer, a high melt strength polypropylene having a branching index g′ of 0.9 or less, a polypropylene having a MFR2 (230° C.) of at least 400.0 g/10 min and a clarifier, wherein the polypropylene composition has a MFR2 (230° C.) of at least 2.0 g/10 min.
Claims19
A polypropylene composition comprising a random propylene copolymer (R-PP), a high melt strength polypropylene (HMS-PP), a polypropylene (B) and a clarifier (C), wherein
- (a) the random propylene copolymer (R-PP)
- (i) comprises units derived from propylene and at least another C2 to C20 α-olefin
- and
- (ii) has a higher branching index g′ than the high melt strength polypropylene (HMS-PP),
- (b) the high melt strength polypropylene (HMS-PP) has a branching index g′ of less than 1.0,
- (c) the polypropylene (B) has a MFR2 (230° C.) measured according to ISO 1133 of at least 400 g/10 min,
- (d) the clarifier (C) comprises at least one α-nucleating agent (N), and
- (e) the polypropylene composition has a MFR2 (230° C.) measured according to ISO 1133 of at least 2.0 g/10 min,
- wherein further,
- (f) the polypropylene (B) is different to the random propylene copolymer (R-PP) at least in view of the melt flow rate MFR2 (230° C.)
- (g) the polypropylene (B) has a higher melt flow rate MFR2 (230° C.) than the high melt strength polypropylene (HMS-PP) and
- (h) the polypropylene (B) has been visbroken.
A method for producing an extrusion blown molded product, comprising the steps of:
- providing a polypropylene composition comprising a random propylene copolymer (R-PP), a high melt strength polypropylene (HMS-PP), a polypropylene (B) and a clarifier (C), wherein
- (a) the random propylene copolymer (R-PP)
- (i) comprises units derived from propylene and at least another C2 to C20 α-olefin
- and
- (ii) has a higher branching index g′ than the high melt strength polypropylene (HMS-PP),
- (b) the high melt strength polypropylene (HMS-PP) has a branching index g′ of less than 1.0,
- (c) the polypropylene (B) has a MFR2 (230° C.) measured according to ISO 1133 of at least 400 g/10 min,
- (d) the clarifier (C) comprises at least one α-nucleating agent (N), and
- (e) the polypropylene composition has a MFR2 (230° C.) measured according to ISO 1133 of at least 2.0 g/10 min,
- wherein further,
- (f) the polypropylene (B) is different to the random propylene copolymer (R-PP) at least in view of the melt flow rate MFR2 (230° C.) and
- (g) the polypropylene (B) has a higher melt flow rate MFR2 (230° C.) than the high melt strength polypropylene (HMS-PP), and
- (h) the polypropylene (B) has been visbroken;
- and
- extruding an extrusion blown molded product using said polypropylene composition.
Extrusion blown molded article comprising a polypropylene composition comprising a random propylene copolymer (R-PP), a high melt strength polypropylene (HMS-PP), a polypropylene (B) and a clarifier (C), wherein
- (a) the random propylene copolymer (R-PP)
- (i) comprises units derived from propylene and at least another C2 to C20 α-olefin
- and
- (ii) has a higher branching index g′ than the high melt strength polypropylene (HMS-PP),
- (b) the high melt strength polypropylene (HMS-PP) has a branching index g′ of less than 1.0,
- (c) the polypropylene (B) has a MFR2 (230° C.) measured according to ISO 1133 of at least 400 g/10 min,
- (d) the clarifier (C) comprises at least one α-nucleating agent (N), and
- (e) the polypropylene composition has a MFR2 (230° C.) measured according to ISO 1133 of at least 2.0 g/10 min,
- wherein further,
- (f) the polypropylene (B) is different to the random propylene copolymer (R-PP) at least in view of the melt flow rate MFR2 (230° C.) and
- (g) the polypropylene (B) has a higher melt flow rate MFR2 (230° C.) than the high melt strength polypropylene (HMS-PP), and
- (h) the polypropylene (B) has been visbroken.
Dependencies are inferred from the claim text.