Telechelic polyimides

Plasticization behaviour induced by condensable gases and vapours (e.g. carbon dioxide, hydrocarbons and other organic vapours) in polymer membranes is stiQ a painful problem in polymeric membrane-based gas separation applications [27,28]. Recently, novel hyperbranched polyimides were prepared from telechelic polyimides and an attempt was made to improve its gas separation performance and physical stability by obtaining plasticization-resistant materials [29-33] (see e.g. Chapters 4, 6 and 7 of this book). 

Recently, hyperbranched polyimides were obtained by selective orderly reaction only at polymer ends using telechelic polyimides with terminal reactive groups of acetylene, vinyl and acryl [29-33],... 

Figure 1.2 presents the effects of UV irradiation time on gas permeability and selectivity for acryl-terminated telechelic polyimide, 6FDA-TeMPD-BEI [33]. It is seen that the gas permeability decreases, while the selectivity increases. 

In the same manner the gas permeability in hyperbranched polyimide prepared from vinyl-terminated telechelic polyimide, 6FDA-TeMPD-PAS is reduced by UV irradiation [32], The gas permeabilities of this polymer after 120min of irradiation are as follows 50Barrer for O2 and 345Barrer for CO2 at 30 °C and latm. The selectivities are 3.5 for... 

Cocondensation of macromers containing trialkoxysilyl groups with modified polystyrene (PS), polyoxazoline, polyimide, polyethylene glycol (PEG), polyether-ketones, polymethyl methacrylate, and derivatives of polytetramethylene oxide was established as convenient procedure for the preparation of telechelic polymer net-... 

Figure 15 Components of a supramolecular polymer blend. Polyimide 9 contains multiple rr-electron deficient chain-folds and the telechelic polyamide 10 is end-capped with electronically complementary pyrenyl residues that intercalate into these folds. ...

Tg measurements have been performed on many other polymers and copolymers including phenol bark resins [71], PS [72-74], p-nitrobenzene substituted polymethacrylates [75], PC [76], polyimines [77], polyurethanes (PU) [78], Novolac resins [71], polyisoprene, polybutadiene, polychloroprene, nitrile rubber, ethylene-propylene-diene terpolymer and butyl rubber [79], bisphenol-A epoxy diacrylate-trimethylolpropane triacrylate [80], mono and dipolyphosphazenes [81], polyethylene glycol-polylactic acid entrapment polymers [82], polyether nitrile copolymers [83], polyacrylate-polyoxyethylene grafts [84], Novolak type thermosets [71], polyester carbonates [85], polyethylene naphthalene, 2,6, dicarboxylate [86], PET-polyethylene 2,6-naphthalone carboxylate blends [87], a-phenyl substituted aromatic-aliphatic polyamides [88], sodium acrylate-methyl methacrylate multiblock copolymers [89], telechelic sulfonate polyester ionomers [90], aromatic polyamides [91], polyimides [91], 4,4"-bis(4-oxyphenoxy)benzophenone diglycidyl ether - 3,4 epoxycyclohexyl methyl 3,4 epoxy cyclohexane carboxylate blends [92], PET [93], polyhydroxybutyrate [94], polyetherimides [95], macrocyclic aromatic disulfide oligomers [96], acrylics [97], PU urea elastomers [97], glass reinforced epoxy resin composites [98], PVOH [99], polymethyl methacrylate-N-phenyl maleimide, styrene copolymers [100], chiral... 

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