Isopropylidene-1 4-phenylene

Poly(anhydrides) are polymers containing the group -C(0)-0-C(0)- in their backbone. Several polyanhydrides such as poly(oxyisophthaloyl), poly(oxycarbonyl-1,4-phenylene methylene-1,4-phenylene carbonyl), poly(oxycarbonyl-1,4-phenylene isopropylidene-1,4-phenylene carbonyl), and poly(oxycarbonyl-1,4-phenylene isobutylidene-1,4-phenylene carbonyl) were synthesized with the expectation of good biodegradability. They do have good hydrolytic stability as opposed to aliphatic polyanhydrides [1]. The structures of these polymers are shown below. 

Polymer poly(oxy- 1,4-phenylene-isopropylidene-1.4-phenylene-oxycarbonyl-N-methylimino-1.4. pherylenemetbylene-1.4-phenylene-N-melhyiimino-carbonyl)... 

Poly(oxyadipoy loxy-1,4-pheny leneisopropylidene-1,4-phenylene) Poly(oxycarbony loxy-1,4-phenylene-isopropylidene-1,4-phenylene) Bisphenol A polycarbonate Poly(oxycarbonylpentamethylene)... 

Poly (oxy-1,4-phenylene-suIfonyl-1,4-phenylene-oxy-1,4-phenylene-isopropylidene- 1,4-phenylene)... 

Poly(oxycarbonyloxy-1,4-phenylene-isopropylidene-1 -4-phenylene) 190 0.0833 Hot stage optical microscopy 310... 

TABLE 49. POLY(OXYCARBONYLOXY-T,4-PHENYLENE-ISOPROPYLIDENE-1,4-PHENYLENE) (PC)... 

The solubility and thermal stability of polymers are usually improved and the surface energy is decreased by substituting fluorine atoms for the hydrogen atoms in the isopropylidene units connecting phenylene units in the main chain. 

The Tg and the Tm of polymers containing aromatic moieties such as phenylene and isopropylidene-bis-4-phenylene (derived from bisphenol A) are high when compared with those of analogous polymers derived from aliphatic-containing reactants. This is the result of both the rigidity of the aromatic portion and the contribution from electron delocalization. 

The introduction of chirality into dendritic assemblies can be easily addressed as shown for Figure 3.4,[l5 which would be named 6-Cascade benzene[3-l,3,5] (5-(3S,4S-l,6-dioxa-3,4-Oisopropylidene-3,4-dihydroxyhexyl)-l,3-phenylene) 4-(3S,4S-l,6-dioxa-3,4-0-isopropylidene-3,4-dihydroxyhexyl)-rm-butylbenzene. 

Selective polyimide membranes, (I), for helium, carbon dioxide, and oxygen were previously prepared by the author [1] by condensing 4,4 -(hexafluoro-isopropylidene) diphthalic anhydride with a 3 2 ratio of 2,4,6-trimethyl-1,3-phenylene diamine and diamino benzoic acid, respectively. 

Sinicropi et al. (1996a) measured hole mobilities of ENA-B doped into a series of polymers poly(styrene) (P-1), bisphenol-A polycarbonate (P-2), pofy(4,4 -isopropylidene bisphenylene-co-4,4 -hexafluoroisopropylidene)bis-phenylene (50/50) terephthalate-co-azelate (65/35) (P-3), poly(4,4 -(2-norbotyli-dene)diphenylene terephthalate-co-azelate (40/60) (P-4), a phosgene-based polyester carbonate (P-5), and poly(vinyl butyral) (P-6). The ENA-B concentrations were 45%. Figure 64 shows the room temperature field dependencies. The mobilities vary by over four orders of magnitude. The field and temperature dependencies were described as log/i fiEl/2 and -(TJT)2. Table S summarizes the results. 

Poly[4,4 -isopropylidene diphenoxy di(4-phenylene)sulfone] (Udel ... 

Poly[4,4 -isopropylidene diphenoxy di(4-phenylene)sulfone] Poly[4,4 -diphenoxy di(4-phenylene)sulfone] Poly[N,N -(p.p,-oxydiphenylene)pyromellitimide]... 

Poly [2,2-propane fe 4-(2,6-dichlorophenyl) carbonate] Poly [2,2-propane te 4-(2,6-dimethylphenyl) carbonate] Poly [3,5-(4-phenyl-1,2,4-triazole)-1,4-phenylene -3,5-(4-phenyl-1,2,4-triazole)-1,3-phenylene] Poly[4,4 -diphenoxy di(4-phenylene)sulfone] Poly[4,4 -isopropylidene diphenoxy di(4-phenylene)sulfone]... 

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