Molding Compositions and Articles Made Thereof

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-E1)n, (S-E1)nS, (S-E1)nX 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 E1 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.

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-E1)n, (S-E1)nS, (S-E1)nX 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 E1 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.