Articles comprising broad molecular weight distribution polypropylene resins

Patent metadata

Field	Value
Publication number	US-9464178-B2
Application number	US-201314434836-A
Country	US
Kind code	B2
Filing date	Oct 8, 2013
Priority date	Oct 31, 2012
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

Disclosed herein are molded articles, foamed articles, and foamable resins comprising a polypropylene resin comprising at least 50 mol % propylene, an MWD (Mw/Mn) of greater than 5, a branching index (g′) of at least 0.95, and a melt strength of at least 20 cN determined using an extensional rheometer at 190° C. Methods of making a molded article and making a foamed article are also disclosed.

First claim

We claim:

1. A molded article comprising a polypropylene resin, wherein the polypropylene resin comprises at least 50 mol % propylene, an MWD (Mw/Mn) greater than 5, a branching index (g′) of at least 0.95, and a melt strength greater than 20 cN determined using an extensional rheometer at 190° C.; wherein the polypropylene resin is produced by contacting propylene monomers at propylene polymerization conditions with a catalyst system comprising a Ziegler-Natta catalyst comprising a non-aromatic internal electron donor and first and second external electron donors comprising different organosilicon compounds.

2. The molded article of claim 1 , wherein the MWD is from 6 to 15 and an MFR from 0.1 to 100, determined according to ASTM D1238 Condition L.

3. The molded article of claim 1 , wherein the melt strength of the polypropylene resin is from 50 cN to 200 cN.

4. The molded article of claim 1 , wherein the polypropylene resin has a viscosity ratio of from 35 to 80 determined from the complex viscosity ratio at 0.01 to 100 rad/s angular frequency at a fixed strain of 10% at 190° C.

5. The molded article of claim 1 , wherein the polypropylene resin has a heat distortion temperature of greater than or equal to 100° C., determined according to ASTM D648 using a load of 0.45 MPa (66 psi).

6. The molded article of claim 1 , wherein the polypropylene resin is an impact copolymer.

7. The molded article of claim 1 , wherein the polypropylene resin comprises from 0.1 to 10 mol % of a comonomer selected from the group consisting of ethylene and C 4 to C 20 olefins.

8. The molded article of claim 1 , wherein the polypropylene resin comprises an isopentad percentage of greater than 95%.

9. The molded article of claim 1 , wherein the polypropylene resin has a stiffness of from 2000 MPa (290 kpsi) to 2500 MPa (360 kpsi) determined according to ASTM D790A on samples nucleated with 0.1% sodium benzoate.

10. The molded article of claim 1 , further comprising greater than or equal to 0.01 wt % of one or more additives selected from the group consisting of: reinforcing fillers; non-reinforcing fillers; scratch resistant agents; plasticizers; antioxidants; phosphites; anti-cling additives; tackifiers; UV stabilizers; heat stabilizers; anti-blocking agents; release agents; anti-static agents; pigments; colorants; dyes; waxes; silica; extender oils; lubricants; talc; anti-fogging agents; foaming agents; flame/fire retardants; blowing agents; vulcanizing agents; curative agents; vulcanizing accelerators; curative accelerators; cure retarders; processing aids; tackifying resins; and a combination thereof.

11. The molded article of claim 1 , wherein the propylene resin is characterized by containing less than 1 gel having a size of 1 micron or larger, wherein the gel content is determined by optical microscopy at 8× magnification of a 5 cm square of a blown film having a thickness of 0.04 mm (1.5 mils).

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Abubakar Saifudin M
• Poloso Anthony
• Meka Prasadarao

Classifications

• C08K3/01

  characterized by their specific function · CPC title

• C08J9/141

  Hydrocarbons · CPC title

• C08J2323/12

  Polypropene · CPC title

• C08J2201/03

  Extrusion of the foamable blend · CPC title

• C08K3/00

  Use of inorganic substances as compounding ingredients · CPC title