Polyropylene resin compositions

A process for preparing a polypropylene resin composition comprising:

• (A) a polypropylene resin treatment product obtained by adding from 0.05 to 5 weight parts of an organic peroxide to 100 weight parts of a polypropylene resin with a melt flow rate of from 0.1 to 50 g/10 min. at a temperature of 230° C. and a load of 2.16 kg and carrying out a melt treatment, wherein said polypolypropylene resin consists of a propylene homopolymer or propylene copolymer, said propylene copolymer consists of propylene and up to 10% by wt. of at least one other α-olefin;
• and
• (B) from 0.01 to 2 weight parts of an oxide of a metal from the periodic table groups 2 or 12 or a metal alkoxide represented by the following general formula (I) to 100 weight parts of the resin content of the polypropylene resin treatment product:
• M(R)m-n(OR′)n (I)
• wherein R and R′ each represent an alkyl group with from 1 to 20 carbon atoms, m is 3 or 4, n is an integer satisfying m>n>2, and M represents boron, aluminum, silicon, or a metal atom of the group 4 or 5 of the periodic table,
• wherein said polypropylene resin composition comprising (A) and (B) comprises a higher melt tension than a polypropylene resin composition comprising (A) but not (B);
• the process comprising adding (A) and (B).

A process for preparing a polypropylene resin composition comprising:

• (A) a polypropylene resin treatment product;
• and
• (B) from 0.01 to 2 weight parts of a metal oxide, the metal oxide comprising a metal from the periodic table groups 2 or 12, or a metal alkoxide represented by general formula (I) to 100 weight parts of the resin content of the polypropylene resin treatment product:
• M(R)m-n(OR′)n (I)
• wherein R and R′ each represent an alkyl group with from 1 to 20 carbon atoms, m is 3 or 4, n is an integer satisfying m>n>2, and M represents boron, aluminum, silicon, or a metal atom of the group 4 or 5 of the periodic table;
• wherein the process comprises:
• adding a polypropylene resin comprising a melt flow rate of from 0.1 to 50 g/10 min. at a temperature of 230° C. and load of 2.16 kg, the polypropylene resin consisting of a propylene homopolymer or propylene copolymer, the propylene copolymer consisting of propylene and up to 10% by wt. of at least one other α-olefin, to from 0.05 to 5 weight parts of an organic peroxide to 100 weight parts of the polypropylene resin;
• melt treating the polypropylene resin and the organic peroxide;
• and
• adding the metal oxide or the metal alkoxide to a product formed from melt treating the polypropylene resin and the organic peroxide.