T. Aoyagi et al., PREPARATION OF PYRIDYL-TERMINATED OLIGODIMETHYLSILOXANE AND SILOXANE-GRAFTED COPOLYMERS CONTAINING PYRIDYL GROUPS AT THE SIDE-CHAIN ENDS, Polymer, 33(7), 1992, pp. 1530-1536
The preparation of hetero difunctional oligodimethylsiloxanes (ODMSs)
was carried out. The ODMSs contained 2-(4-pyridyl)ethyl (Py) or 2-(2,6
-di-t-butyl-4-pyridtl)ethyl (DBPy) at one end and a reactive group, su
ch as 3-methacryloxypropyl (MP) or hydrosilyl (H), at the other end. T
hese oligosiloxanes were prepared by anionic ring-opening polymerizati
on of hexamethylcyclotrisiloxane (D3) initiated with silanolate anions
containing pyridyl groups. To obtain the initiators, novel silanol co
mpounds containing Py or DBPy groups were prepared from 4-methylpyridi
ne and 2,6-di-t-butyl-4-methylpyridine, respectively. The average degr
ee of polymerization could be controlled by changing the ratio of D3 a
nd the initiator. Py-ODMS-MP and DBPy-ODMS-MP were copolymerized with
methyl methacrylate or butyl methacrylate hydrosilylation of DBPy-ODMS
-H with vinyldimethylsilated polysulphone (PSF) was carried out to aff
ord PSF/DBPy-ODMS graft copolymer. The gas permeability coefficients o
f nitrogen, oxygen and carbon dioxide for the copolymer membranes were
evaluated.