Amorphous phenoxy thermoplastics with an extraordinary barrier to oxygen

High-Barrier Poly(hydroxy amide ethers): Effect of Polymer Structure on Oxygen Transmission Rates. 3

“…60,61 This is reflected by the fact that the barrier properties for poly(hydroxy amide ethers) 23-39 improve (i.e., O 2 TR decreases) as the aromatic core unit (Ar) either (a) becomes less bulky and more compact or (b) contains strong hydrogen bonding groups. 14 In the sections that follow, the 17 poly(hydroxy amide ethers) shown in Table 4 (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39) are compared to one another to show the effects that key structural features have on O 2 TR in the polymers.…”

“…In other polymers, such as certain polyamides, subtle structural variations in the polymer backbone have been found to affect the oxygen barrier properties of the polymers. 5 An additional, emerging class of high-barrier polymers are "phenoxy-type" thermoplastics (1), [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] prepared by the reactions of aromatic diglycidyl ethers with bisphenols, primary amines, bis-secondary amines, dicarboxylic acids, dithiols, bis-N,N′-dialkyldisulfonamides, and other dinucleophilic species. It is believed that the high barrier properties of phenoxy-type thermoplastics are due, in part, to the ability of the polymer chains to pack efficiently, which impedes the migration of oxygen and other gases through the polymer matrix.…”

Transport properties of thermoplastic/thermoset blends

“…Indeed, the values calculated with the Maxwell law are, respectively, 3.4 barrers for O 2 and 15.5 barrers for CO 2 .…”

“…The extrapolation for d ϭ 0 of the experimental straight dotted lines gives the permeability coefficients of the continuous phase, respectively, 8 barrers for O 2 and 32 barrers for CO 2 . These values are almost twofold lower than the values measured on PPE.…”

“…Recently, new high barrier quite amorphous thermoplastics have been synthetized using amide containing bisphenols and leading to polyhydroxyamide ethers 1 or using epoxy amine reactions and leading to linear polyaminoethers. [2][3][4] Compared to this last class of polymers, epoxy/ amine networks are based on the same chemistry and they have also relatively low gas permeability coefficients. Nevertheless, they present two disadvantages: the first one is the impossibility of using a conventional extruder as a processing method and the second one is to be more brittle than linear polymers.…”