Polymer compositions with improved surface properties

A method for improving the surface properties of a polymer composition formed of a thermoset resin polymer which comprises adding to the polymer between about 0.01 to about 10 parts by weight of the composition of an additive of the formula:

• R—SiR12—[O—SiR1R2]x—[O—SiR1Z]y—O—SiR12—R
• in which
• Z is a radical with the structure —[O—SiR1R2]n—O—SiR12—R
• R is a hydroxyl or methyl radical;
• R1 is a methyl radical;
• R2 is selected from the group consisting of a C1 or a C12-C75 saturated hydrocarbon radical;
• x is greater than 15;
• y is 0-50;
• and
• n is 0-50
• wherein at least 10% of the siloxane units present in the additive compound are not di-methyl siloxanes, and wherein the remainder of the siloxane units are di-methyl siloxanes.

A polymer composition having improved surface properties, the composition comprising:

• a) a thermoset resin polymer;
• and
• b) at least one melt processable, organo-modified siloxane additive capable of reducing the COF of the polymer composition of the formula:
• R—SiR12—[O—SiR1R2]x—[O—SiR1Z]y—O—SiR12—R
• in which
• Z is a radical with the structure —[O—SiR1R2]n—O—SiR12—R
• R is a hydroxyl or methyl radical;
• R1 is a hydroxyl or methyl radical;
• R2 is selected from the group consisting of a C1, an alkoxylate or a C12-C75 saturated or unsaturated, hydrocarbon radical;
• and
• x is greater than 15;
• y is 0-50
• n is 0-50
• wherein at least 10% of the siloxane units present in the additive compound are not di-methyl siloxanes, and wherein the remainder of the siloxane units are di-methyl siloxanes, and wherein if R2 is an alkoxylate the percent of non-dimethyl siloxane groups that contain the alkoxylate is between 5 to 75%.