Basf Aktiengesellschaft

The University of Akron

Basf Se Corporation

Bela Ivan

Arno Lange

Hans Peter Rath

Helmut Mach

Ulrich Karl

Tibor Pernecker

Zsuzsanna Tamara Nagy

Peter Werner Groh

Viktoria Palfi

Joseph F Kennedy

Viktória Palfi

Péter Werner Groh

The present invention relates to a process for preparing carboxyl-terminated polyisobutenes by ozonolysis of polyisobutenes terminated by an ethylenically unsaturated double bond.

Method for producing carboxyl-terminated polyisobutenes

The synthesis of poly(isobutylene-b-methyl vinyl ether) (PIB-b-PMeVE) by living carbocationic polymerization (LC.sym.Pzn) employing the sequential monomer addition (SMA) technique is described. The process starts by producing the living PIB.sym. block employing the 2-chloro-2,4,4-trimethylpentane (TMPC11/TiCl.sub.4 initiating system in the presence of the common ion salt tetra-n-butylammonium chloride (n-Bu.sub.4 NCl) in CH.sub.3 Cl/n-C.sub.6 H.sub.14 or CH.sub.2 Cl.sub.2 /n-C.sub.6 H.sub.14 mixed solvents at -80.degree. C. and continues by the addition of methyl vinyl ether (MeVE). The second living block forms only in the presence of excess TiCl.sub.4 suggesting that the species that starts the second block and subsequently sustains its growth is a MeVE.multidot.TiCl.sub.4 complex. The stoichiometry of this complex (1:1 or 1:2) is uncertain. The TiCl.sub.4 remains attached to the MeVE units after their incorporation into the diblock, however, it can be readily removed by water. PMeVE obtained in the presence of excess TiCl.sub.4 degrades by dealcoholation, however, degradation is prevented by the use of n-Bu.sub.4 NCl. Various length (composition) diblocks have been prepared and characterized. The novel PIB-b-PmeVE's exhibit strongly amphiphilic character.

Living carbocationic polymerization of poly(isobutylene-.beta.-methyl

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Budapest, Hungary

Bela Ivan