Premium
Synthesis of acetoxyphenyl‐ and hydroxyphenyl‐terminated polyfunctional T 8 , T 10 , T 12 silsesquioxanes and initial studies on their use in the formation of highly crosslinked polyesters
Author(s) -
Jung Jae Hwan,
Chou Kathleen,
Furgal Joseph C.,
Laine Richard M.
Publication year - 2013
Publication title -
applied organometallic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.53
H-Index - 71
eISSN - 1099-0739
pISSN - 0268-2605
DOI - 10.1002/aoc.3054
Subject(s) - chemistry , metathesis , polyester , polymer chemistry , hydrolysis , polymer , linker , condensation polymer , yield (engineering) , salt metathesis reaction , chloride , organic chemistry , polymerization , materials science , computer science , operating system , metallurgy
There is continuing interest in the synthesis of polyhydroxy‐terminated molecular species for diverse applications ranging from photolithographic materials to intermediates in the synthesis of porous, crosslinked polymers as media for molecular separations, drug delivery etc. We describe here the use of [vinylSiO 1.5 ] 8 and [vinylSiO 1.5 ] 10/12 mixtures to synthesize first‐ and second‐generation acetoxyphenyl compounds via metathesis with p ‐acetoxystyrene (generation 1, GEN1) or metathesis with p ‐bromostyrene followed by Heck coupling with p ‐acetoxystyrene (generation 2, GEN2). The resulting acetoxy compounds were then hydrolyzed to produce octa‐, deca‐ and dodecahydroxy GEN1 and GEN2 compounds. These compounds were purified and then reacted with adipic acid chloride to form the first examples of highly crosslinked polyesters based on silsesquioxanes. The coupling products, their hydrolyzed products and the crosslinked polymers were characterized using a variety of spectroscopic methods. In general, the observed specific surface areas were less than 5 m 2 g −1 ; however, the T 8 GEN1 derivative gave a surface area of 25 m 2 g −1 and was the only crosslinked polymer with a TGA ceramic yield that matched theory for ‘perfect’ crosslinking. This crosslinked polyester has the shortest organic linker between cages and despite the highly flexible C 6 linker provides continuing evidence that it is possible to use the cubic symmetry in these materials to build well‐ordered 3‐D nanocomposite structures. Copyright © 2013 John Wiley & Sons, Ltd.