改性甲基铝氧烷活化的铁系催化剂聚合异戊二烯

MODIFIED METHYLALUMINOXANE ACTIVITED IRON BASED CATALYST FOR ISOPRENE POLYMERIZATION

研究了改性甲基铝氧烷(MMAO)为助催化剂的乙酰丙酮铁(Fe(acac)3)/二乙基亚磷酸酯(DEP)催化剂作用下的异戊二烯(IP)聚合。考察了MMAO和DEP的用量、铝化合物和溶剂的种类对聚合的影响。结果表明,该催化剂在甲苯溶液中,50℃,相对较低的MMAO用量下([A]/[Fe]=20)及[DEP]/[Fe]=2.0时有高的催化活性。所得聚合物具有较高的3,4(含1,2)结构含量(约为60%)及较窄的分子量分布(Mw/Mn=2.0～2.5)。

The modified methylaluminoxane (MMAO) activated iron(Ⅲ) acetylacetonate (Fe(acac)_3)/diethyl phosphite (DEP) catalyst was examined in isoprene polymerization at 50 ℃, with respect to the effects of the amount of MMAO and DEP, the type of aluminum compound and solvent. The catalyst proved to be highly effective in toluene, achieving optimum activity at a relatively low MMAO level ([Al]/[Fe]=20) and [DEP]/[Fe] ratio at (2.0). The produced polymers possessed 3,4(+1,2) content of ca. 60% and relatively narrow molecular weight distribution (_w/_n=(2.0)^(2.5)).