| abstract |
THIS INVENTION REFERS TO A METHOD FOR VARIETY OF MELECULAR POINTS AND MOLECULAR WEIGHTS OF SYNDIOTACTIC POLYOLEFINES THROUGH THE USE OF METALLOCENE CATALYZERS WITH ARYL RINGS OF A FLUORENE LIGAND. THE PRESENCE OF ELECTRONIC DONOR SUBSTITUTES SUCH AS, FOR EXAMPLE, THE DIALKILAMINO, HALOGEN AND ALCOXY GROUPS, IN FLUORENE IN C1, C2, C3 OR C2 AND C7, MAKE THE CATALYST LESS ACTIVE AND DECREASE THE MOLECULAR WEIGHT. ELECTRONIC DONOR SUBSTITUTES, SUCH AS ALKYL, DIALKYLAMINE, HALOGEN, OR ALCOXY IN C4, NOT ONLY INCREASE THE EFFICIENCY OF THE CATALYST BUT ALSO INCREASELY INCREASE THE MOLECULAR WEIGHT OF THE POLYMER. MANY BODY HYDROCARBON SUBSTITUTES SUCH AS THE ALKILO, CICLOALKILO AND ARILO GROUPS IN C2 AND C7 INCREASE THE MELTING POINT. MUCH BODY SUBSTITUTES SUCH AS THE HYDROCARBON GROUP TYPE ALKILO, CICLOALKILO, ARILO, ALCOXI AND DIALKILAMINO GROUPS, ETC. IN C4 / C5 DECREASE THE MELTING POINT. THE PRESENCE OF MULTIPLE SUBSTITUTES IN FLUORENE, HAS ADDITIVE EFFECTS. |