Synthesis and characterization of poly(aryl ether–sulfone) and poly(tetrahydrofuran)(A–B)_Nblock copolymers

Abstract

The preparation of (A-B), block copolymers comprising of poly(ary1 ether-sulfone) (PSF) and poly(tetrahydr0furan) (PTHF) segments have been described. Pyridine-terminated PSF oligomers of controlled molecular weights were synthesized via nucleophilic aromatic substitution reactions. PTHF oligomers prepared by living cationic ring-opening polymerization processes using trifluoromethanesulfonic anhydride as the initiator, were terminated with the PSF oligomers. The resulting block copolymers with quaternary nitrogen linkages along the backbone were characterized by a variety of techniques including spectroscopy, and thermal and chromatographic analysis.Poly(ary1 ether-sulfone) (PSF, 1) and related materials have received substantial academic and industrial interest.' In spite of a series of important characteristics, PSF is hydrophobic, which precludes its use as a membrane material in aqueous systems. Previous attempts at imparting hydrophilicity to the PSF backbone include sulfonation followed by neutralization2 and preparation of block copolymers with water-soluble poly(ethy1ene oxide) ( PEO).3 These block copolymers were synthesized by the coupling reactions of PSF with terminal phenolic groups and PEO with hydroxy end groups with phosgene. Detailed characterization studies were not reported.PTHF contributes various desirable properties to the block copolymer system including hydrophilicity, hydrolytic stability, high abrasion resistance and excellent elastomeric properties such as low hysteresis, high flexibility and impact resistance at low temperature. Block copolymers of a polystyrene hard segment and poly( tetrahydrofuran) (PTHF) as the soft segment with AB, ABA and (A-B), architecture have been ~r e p a r e d .~We have extended the scope of PTHF-containing block copolymers to the preparation of PSF-PTHF (2). The aryl ether sulfone blocks of controlled molecular weights were prepared by the reactions of 4,4'-isopropylidenediphenol (bisphenol-A), 4,4'-dichlorodiphenyl sulfone (DCD PS) and 4-hydroxypyridine. Difunctionally active PTHF segments of desired lengths were prepared by living-ring opening cationic polymerization of tetrahydrofuran (THF) with t rifluoromethanesulfonic anhydride (TFMA). The structures of these block copolymers resemble those of PTHF-based ionenes (3,4).5,6 In this article, the synthesis and analysis of model compounds, the PSF and PTHF oligomers and the block copolymers will be described. Characterization techniques include, thermal, spectroscopic, chromatographic and intrinsic viscosity measurements. ExperimentalMaterials THF (Aldrich) was refluxed over sodium for 12 h. Benzophenone was added and the deep-purple solution was c r 2 4 Y = Spacer Group X = CI, Br

Poly(aryl ether sulfide)s by sulfide-activated nucleophilic aromatic substitution polymerization

“…DeSimone has researched poly(aryl ether)s with kinks in the polymer chain from 2,5-thiophene units in the monomers [38][39][40][41]. Mohanty has studied the activation of aryl fluorides by diazo groups, the synthesis of block copolymers of poly(aryl ether)s, and competitive radical reactions [42][43][44][45][46][47][48]. We have also been active in this area through the investigation of azomethines as activating groups [49] and through continuing recent research on the activation of aryl fluorides for nucleophilic aromatic substitution by using groups that are not strong electron withdrawing groups, but which can activate the substitution by electron accepting means [50,51].…”

Porous Polymers Derived from Octavinylsilsesquioxane by Cationic Polymerization

“…The development of novel porous materials is a rapidly growing field in recent years and has aroused great concerns . A wide variety of covalently linked porous polymers have been exploited, such as periodic mesoporous organosilicas, hyper‐cross‐linked polymers, polymers of intrinsic microporosity, conjugated microporous polymers, porous aromatic frameworks and covalent organic frameworks .…”

“…In particular, covalently linked porous materials are of scientific and technological interest because of their high stability, surface properties, tunable pore size and framework, chemical functions, and flexible synthetic methods. The past decade has seen a large number of significant breakthroughs in the design and synthesis of novel porous materials, driven by the rapid growth of emerging applications . Especially in the chemical field, the application of porous materials is more extensive, such as catalysis, ion exchange, adsorption and separation, sensing, chromatography, and energy storage .…”

“…The development of novel porous materials is a rapidly growing field in recent years and has aroused great concerns. [1][2][3][4] A wide variety of covalently linked porous polymers have been exploited, such as periodic mesoporous organosilicas, [5] hyper-cross-linked polymers, [6,7] polymers of intrinsic microporosity, [8,9] conjugated microporous polymers, [10][11][12] porous aromatic frameworks [13,14] and covalent organic frameworks. [15][16][17] In particular, covalently linked porous materials are of scientific and technological interest because of their high stability, surface properties, tunable pore size and framework, chemical functions, and flexible synthetic methods.…”

Synthesis and Gas Storage Application of Hierarchically Porous Materials

“…Also, in materials science, hierarchically porous materials have recently been extensively investigated for different applications such as catalysis, biomaterial engineering, separation, filters, electronics, and optoelectronics . These POFs exhibit high physicochemical stability.…”