Poly(hydroxy amide ethers):  New High-Barrier Thermoplastics

The synthesis of a new class of high-barrier polymers, poly(hydroxy amide ethers), is described. The polymers are formed by the reactions of bisphenol-A diglycidyl ether, OCH 2 CHCH 2 OC 6 H 4 C(CH 3 ) 2 C 6 H 4 OCH 2 CHCH 2 O, and amide-containing bisphenols of the general formula HOC 6 H 4 NHC(O)RC(O)NHC 6 H 4 OH [R = −(CH 2 ) n −, −CH 2 C 6 H 4 CH 2 −, or −C 6 H 4 −] or HOC 6 H 4 NHC(O)C 6 H 4 OH at 140−160 °C in propylene glycol monophenyl ether solvent using ethyltriphenylphosphonium acetate as initiator. High-molecular-weight poly(hydroxy amide ethers) of the general structure [−CH 2 CH(OH)CH 2 OC 6 H 4 C(CH 3 ) 2 C 6 H 4 OCH 2 CH(OH)CH 2 OC 6 H 4 NHC(O)RC(O)NHC 6 H 4 O−] n or [−CH 2 CH(OH)CH 2 OC 6 H 4 C(CH 3 ) 2 C 6 H 4 OCH 2 CH(OH)CH 2 OC 6 H 4 NHC(O)C 6 H 4 O−] n are readily prepared. The amorphous thermoplastics have glass transition temperatures ( T g ) of 90−133 °C and oxygen transmission rates (O 2 TR) which range from 0.7 to 4.6 cc·mil/100 in. 2 ·atm·day (barrier units or BU) at 23 °C and 47−85% relative humidity. The effect that polymer structure has on oxygen barrier properties and T g is described. The characterization, structure determination, and properties of the poly(hydroxy amide ethers), as well as the amide-containing bisphenol precursors, are also presented.