| 主权项 |
1. A polycarbonate blend composition comprising:
(a) a first polycarbonate having a glass transition temperature of greater than 170° C. as measured using a differential scanning calorimetry method, wherein the first polycarbonate is derived from:
(i) one or more monomers having the structure HO-A1-Y1-A2-OH wherein each of A1 and A2 comprise a monocyclic divalent arylene group, and Y1 is a bridging group having one or more atoms; or(ii) polyester monomer units having the structure wherein D comprises one or more alkyl containing C6-C20 aromatic group(s), or one or more C6-C20 aromatic group(s), and T comprises a C6-C20 aromatic group; and (b) a second polycarbonate wherein the second polycarbonate is a polysiloxane block copolymer derived from
(i) the structure wherein R comprises a C1-C30 aliphatic, a C6-C30 aromatic group, or a combination thereof, wherein Ar comprises one or more C6-C30 aromatic group(s), or one or more alkyl containing C6-C30 aromatic group(s), wherein E has an average value of 20-200; or(ii) the structure wherein R comprises a C1-C30 aliphatic, a C6-C30 aromatic group, or a combination thereof, wherein R6 comprise C6-C30 aromatic group, or a combination of a C6-C30 aromatic group and a C1-C30 aliphatic group, wherein E has an average value of 20-200; wherein the wt % siloxane of (b) is between 1-25%; (c) an anti-drip agent having a specific gravity of at least 1.52 g/cc, according to ASTM D 792-10, and an average particle size of 400 J/m comprising
(i) a perfluorinated polyolefin;(ii) a unit derived from and(iii) a unit derived from acrylonitrile and (d) a flame retardant additive; wherein the wt % of siloxane of the blended composition is between 1.5 and 5%; wherein the blend composition has a heat deflection temperature (HDT) of at least 150° C. at 1.8 MPa, according to ASTM D 648-07; wherein the blend composition has a vicat softening temperature (Vicat B/50) of at least 170° C., according to ASTM D 1525-09; and wherein a molded article from the blend composition has a UL94 rating of V0 at 1.5 mm thickness. |
