POLYMER INITIATOR SYSTEM BASED ON ORGANIC HYDROXIDE AND DISUBSTITUTED BORANE

摘要

This invention discloses a new class of radical initiator system that is based on a combination of organic hydroxide initiator and disubstituted borane activator. By mixing an organic hydroxide (R(-Q-OH)n) such as alcohol and/or hydroperoxide with disubstituted borane (H- B(RB)2), a facile reaction takes place to form an intermediate that can be used to initiate polymerization of a variety of monomers. The polymerization can involve the decomposition of an intermediate comprising borinate (R[-Q-O-B((RB)2]n) to form an organic radical (R(- Q*)n) and a boryloxy radical (n[*O-B((RB)2]). The former organic radical is active in initiating polymerization of vinyl monomers. On the other hand, the boryloxy radical is too stable to initiate polymerization due to the back-donating of electron density to empty p-orbital of boron. This initiator system provides a versatile method to prepare not only colorless odorless vinyl polymers but also block and graft molecular structures.