| 摘要 |
<p>Thermoplastic polymer blend comprises a mixt. of (a) an aromatic polycarbonate, (b) an ABS copolymer and (c) a N,N'-alkylene-bis-(tetrahalogen-phthalimide) (I). The (I) is added in an amt. (esp. 3-20wt.% w.r.t. the polyblend) sufficient to give the compsn. a UL-94 grade of V-O at a thickness of 3.2 mm and with improved UV resistance and melt stability. The (I) may be used in conjunction with an antimony cpd. e.g. in an amt. of 2-8 wt.% Sb (w.r.t. total polyblend) to give a UL-94 rating of V-O at a thickness of 1-6 mm. Pref. (I) has the formula (I) (where R = 1-6C alkylene and Hal = halogen atoms (same or different). (I) is esp. N,N'-ethylenebis(tetrabromophthalimide) (III). Pref. the compsn. contains 10-90wt.% ABS, 10-90 wt.% aromatic polycarbonate, e.g. a bisphenol A polycarbonate, 2-8wt.% Sb and 3-20wt.%(I). A mixt. of 55 pts. wt. bisphenol A polycarbonate, 45 pts. wt. ABS, 4 pts. wt. SB2O3 and 8 pts. wt. (II) was dried overnight and extruded in a single screw extruder. The prod. has a UL-94 rating of V-O at 1.6 mm znc, 3.2 mm thickness'; a UV resistance DELTA E total colour change (ASTM E-308-66 (1973)) of 26.9, a change in yellowing index DELTA YI (ASTM D-1925-63T) of 20.5; and an Instron melt stability at 260 degrees C of 1760 pas after 5 mins and 1240 pas after 65 mins (70% retention).</p> |
