New method for the synthesis of fully aliphatic telechelic α,ω-dihydroxy-polyisobutyleneElectronic supplementary information (ESI) available: See DOI: 10.1039/c4py00569d

• Main Authors: Castano, Marcela, Becker, Matthew L, Puskas, Judit E
• Format: Journal Article
• Language: English
• Published: 12.08.2014
• ISSN: 1759-9954; 1759-9962
• DOI: 10.1039/c4py00569d

This paper reports a new method for the synthesis of α,ω- primary -dihydroxy PIBs (HO-PIB-OH) with a fully aliphatic backbone. Three aliphatic difunctional initiators with tertiary -methoxy, tertiary -chloride and tertiary -hydroxyl end groups (TMHDiOMe, TMHDiCl and TMHDiOH) were screened in conjunction with TiCl 4 and DMA in a solution system (hexane-CH 3 Cl, 60/40, v/v). TMHDiOMe yielded only traces of PIB, while TMHDiOH and TMHDiCl yielded PIBs with a mixture of end group structures. The same initiators were also screened in heterogeneous systems (CH 3 Cl or CH 2 Cl 2 ). TMHDiOMe/TiCl 4 yielded no polymer in either diluent, CH 3 Cl, and TMHDiOH/TiCl 4 led to olefinic end groups. While TMHDiCl/TiCl 4 resulted in clean Cl-PIB-Cl in CH 3 Cl, the I eff values were low and TMHDiCl was very unstable and difficult to isolate. Premixing TMHDiOH with TiCl 4 in CH 3 Cl led to the in situ formation of TMHDiCl. Addition of hexane and IB, followed by end-capping with allyltrimethylsilane resulted in the formation of allyl-PIB-allyl. Click chemistry with HS-CH 2 -CH 2 -OH yielded α,ω- primary -dihydroxy-PIB (HO-PIB-OH) with M n = 4085 g mol −1 and M = 1.2. 1 H-NMR analysis verified the structure of the HO-PIB-OH. This paper reports a new method for the synthesis of α,ω- primary -dihydroxy PIBs (HO-PIB-OH) with a fully aliphatic backbone.