PROCESS FOR THE PREPARATION OF POLYALKENYLSUBSTITUTED SUCCINIC ANHYDRIDE, THE PRODUCT SO PREPARED, AND A LUBRICATING OIL COMPOSITION CONTAINING THE PRODUCT

摘要

PROCESS FOR THE PREPARATION OF POLYALKENYLSUBSTITUTED SUCCINIC ANHYDRIDE, THE PRODUCT SO PREPARED, AND A LUBRICATING OIL COMPOSITION CONTAINING THE PRODUCT The preparation of PIB/MALA in high yields (> 90%) by reacting polyisobutene (PIB) with maleic anhydride (MALA) in the presence of chlorine has the disadvantage of causing a relatively high chlorine percentage (? 6%w) in the PIB/MALA product. An after-reaction without chlorine addition (in the presence of excess MALA) results, after MALA has been stripped off, in a product with a chlorine percentage of ? 0.4%w. This percentage can now be further decreased to < 0.2%w when subjecting the PIB/MALA product to a thermal treatment at about 200.degree.C after excess MALA has been stripped off.