Molding compositions and articles made thereof

1. An injection molded article formed from a molding composition consisting essentially of:

a) 15-80 wt. % of a hydrogenated styrenic block copolymer having a general formula: S-E-S, (S-E 1 ) n , (S-E 1 ) n S, (S-E 1 ) n X or mixtures thereof, n has a value of 2 to 6 and X is a coupling agent residue,

wherein prior to hydrogenation,

the S block is a polystyrene block having a molecular weight from 5,000 to 7,000,

the E block is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a molecular weight of from 30,000 to 70,000,

the E 1 block is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a molecular weight of from 15,000 to 35,000;

b) 10-60 wt. % of a polypropylene; and

c) 5-25 wt. % of a thermoplastic vulcanizate;

wherein the hydrogenated styrenic block copolymer has a melt index of at least 12 g/10 minutes according to ASTM D1238 at 230° C. and 2.16 kg weight;

wherein the polypropylene has a melt flow index greater than 300g/10 min as measured according to ISO 1133-1 condition 230° C./2.16 kg;

wherein the thermoplastic vulcanizate has a Shore A hardness from 60-90 (15 sec, 23° C.) as measured according to ISO 868;

wherein the molding composition has a melt flow index of 50-350 g/10 (230° C., 2.16 kg) as measured by ASTM D1238-04; and

wherein the injection molded article, after 10 days of aging at 120° C., has a % gloss increase of less than 100, relative to an initial gloss, as determined by PSA D47 1850.

2. The article of claim 1 , wherein the thermoplastic vulcanizate is a dynamically vulcanized alloy consisting essentially of fully cured ethylene propylene diene methylene rubber particle encapsulated in a polypropylene matrix.

3. The article of claim 1 , wherein the thermoplastic vulcanizate has a density of from 0.880 to 0.980 g/cm 3 as measured by ISO 1183.

4. The article of claim 1 , wherein the molding composition forms a layer having a thickness of at least 0.5 mm.

5. The article of claim 1 , wherein the polypropylene is selected from: (i) a homopolymer of propylene, (ii) a random copolymer of propylene and an olefin selected from ethylene and C 4 -C 10 α-olefins, and (iii) a random terpolymer of propylene with two α-olefins selected from the group of ethylene and C 4 -C 10 α-olefins.

6. The article of claim 1 , further comprising from 1-15 wt. % of one or more additives selected from the group consisting of a nucleating agent, a clarifier, a release agent, a plasticizer, an antioxidant, a thermal stabilizer, a visible light stabilizer, an ultraviolet light stabilizer, a colorant, a flame retardant, a lubricant, a synergist, a mold release agent, a flow enhancer, an anti-static agent, a filler, a scratch resistance additive, and a surface modifier.

7. The article of claim 1 , wherein the article is formed by any of injection molding, overmolding, rotomolding, thermoforming, casting, extrusion, profile extrusion, and blow molding.

8. The article of claim 1 , wherein the article is a vehicle interior product having positive scratch resistance, wherein the article is selected from interior trim, interior sheathing, door panels, instrument panels, and consoles.

9. The article of claim 1 , having a gloss at 60° C. of less than or equal to 10 as measured by PSA D47 1850.

10. The article of claim 1 , having a gloss after 10 days of aging at 120° C. of less than or equal to 15 as measured by PSA D47 1850.

11. A method of preparing an injection molded article formed by:

(a) forming a molding composition, said molding composition consisting essentially of:

a) 15-80 wt. % of a hydrogenated styrenic block copolymer having a general formula: S-E-S, (S-E 1 ) n , (S-E 1 ) n S, (S-E 1 ) n X or mixtures thereof, n has a value of 2 to 6 and X is a coupling agent residue,

wherein prior to hydrogenation,

the S block is a polystyrene block having a molecular weight from 5,000 to 7,000,

the E block is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a molecular weight of from 30,000 to 70,000,

the E 1 block is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a molecular weight of from 15,000 to 35,000;

b) 10-55 wt. % of a polypropylene; and

c) 5-20 wt. % thermoplastic vulcanizate; and

(b) forming the injection molded article from the molding composition by injection molding, overmolding, rotomolding, thermoforming, casting, extrusion, profile extrusion, or blow molding;

wherein the injection molded article after 10 days of aging at 120° C. has a gloss that is at least 100% greater than the gloss of the article prior to the aging, as determined by PSA D47 1850.

12. The method of claim 11 , wherein the molding composition has a melt flow index of 50-350 g/10 (230° C., 2.16 kg) as measured by ASTM D1238-04.

13. The method of claim 11 , wherein step (b) comprises forming a layer having a thickness of at least 0.5 mm.

14. The method of claim 11 , wherein the article is a vehicle interior product having positive scratch resistance, wherein the article is selected from interior trim, interior sheathing, door panels, instrument panels, and consoles.

15. An injection molded article formed from a molding composition consisting essentially of:

a) 40-80 wt. % of a hydrogenated styrenic block copolymer having a general formula: S-E-S, (S-E 1 ) n , (S-E 1 ) n S, (S-E 1 ) n X or mixtures thereof, n has a value of 2 to 6 and X is a coupling agent residue,

wherein prior to hydrogenation,

the S block is a polystyrene block having a molecular weight from 5,000 to 7,000,

the E block is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a molecular weight of from 30,000 to 70,000,

the E 1 block is a polydiene block, selected from the group consisting of polybutadiene, polyisoprene and mixtures thereof, having a molecular weight of from 15,000 to 35,000;

b) 15-40 wt. % of a polypropylene; and

c) 10-20 wt. % of a thermoplastic vulcanizate;

wherein the hydrogenated styrenic block copolymer has a melt index of at least 12 g/10 minutes according to ASTM D1238 at 230° C. and 2.16 kg weight;

wherein the polypropylene has a melt flow index greater than 300 g/10 min as measured according to ISO 1133-1 condition 230° C./2.16 kg;

wherein the thermoplastic vulcanizate has a Shore A hardness from 60-90 (15 sec, 23° C.) as measured according to ISO 868;

wherein the molding composition has a melt flow index of 50-250 g/10 (230° C., 2.16 kg) as measured by ASTM D1238-04; and

wherein the injection molded article, after 10 days of aging at 120° C., has a % gloss increase of less than 100, relative to an initial gloss, as determined by PSA D47 1850.

16. The article of claim 15 , wherein the thermoplastic vulcanizate is a dynamically vulcanized alloy consisting essentially of fully cured ethylene propylene diene methylene rubber particle encapsulated in a polypropylene matrix.

17. The article of claim 15 , wherein the polypropylene is selected from: (i) a homopolymer of propylene, (ii) a random copolymer of propylene and an olefin selected from ethylene and C4-C 10 α-olefins, and (iii) a random terpolymer of propylene with two α-olefins selected from the group of ethylene and C 4 -C 10 α-olefins.

18. The article of claim 15 , further comprising from 1-15 wt. % of one or more additives selected from the group consisting of a nucleating agent, a clarifier, a release agent, a plasticizer, an antioxidant, a thermal stabilizer, a visible light stabilizer, an ultraviolet light stabilizer, a colorant, a flame retardant, a lubricant, a synergist, a mold release agent, a flow enhancer, an anti-static agent, a filler, a scratch resistance additive, and a surface modifier.

19. The article of claim 15 , wherein the article is formed by any of injection molding, overmolding, rotomolding, thermoforming, casting, extrusion, profile extrusion, and blow molding.

20. The article of claim 15 , wherein the article is a vehicle interior product including interior trim, interior sheathing, door panels, instrument panels, and consoles, having good heat stability, scratch resistance, and improved gloss values after aging.