Gas Permeation through Poly(N-n-alkylmaleimide) Membranes

Abstract

ABSTRACT:The permeation of oxygen and nitrogen through the membranes of poly-(N-n-alkylmaleimide )s including poly(N-n-butylmaleimide) [poly(nBMI)] and poly(N-dodecylmaleimide) [poly(DodMI)] was investigated. These membranes from polymaleimides have been revealed to have high permeability coefficients even under their glass transition temperatures on account of facile permeation through the fused alkyl chain in the side group. The apparent diffusion coefficient was determined to be greater than 10-6 cm 2 s-1 for poly(DodMI), and the facile diffusion in the polymer was discussed.KEY WORDS N-n-Alkylmaleimide / Poly(substituted methylene) / Glass Transition Temperature / Gas Permeability / Permeability Coefficient / Diffusion Coefficient / Mobility of Side Chain / Membrane / number of the side chain increases. Gas transport properties of polyimide films which have a variety of chemical structures have been reported on account of a high glass transition temperature and excellent thermal stability. 1 -10 We reported on the radical polymerization of N-alkyl-substituted maleimides and N-(alkyl-substituted phenyl)maleimides bearing various alkyl groups, and on the excellent thermal stability of the resulting polymers. 11 In the previous paper, 12 • 13 we also reported that radical polymerization of N-nalkylmaleimides (RMI) with various kinds of n-alkyl groups as an N-substituent proceeded easily to give high molecular weight polymers in high yields. The polymer membranes prepared by casting show high permeability to oxygen and nitrogen, i.e., permeability coefficients (P 02 and PN) are in the range of 10-9 to 10-8 cm 3 (STP)cmcm-2 s-1 cmHg-1 , although they are glassy polymers with high glass transition temperatures. It has been revealed that permeability depends on the length of the alkyl side chain, i.e., P increases as the carbon In this study, gas permeation through the polymer membranes of poly(N-n-butylmaleimide) [poly(nBMI), n=4] and poly(N-dodecylmaleimide) [poly(DodMI), n= 12] as well as other poly(RMl)s (Scheme I) was investigated and the permeation mechanism is discussed.

Synthesis of heat- and solvent-resistant polymers by radical polymerization of trifluoromethyl-substitutedN-phenylmaleimides

“…4,23 The PhMI with 2-alkoxycarbonyl substituents also showed similar polywere determined by thermogravimetric analysis in a nitrogen stream at a heating rate of 10ЊC/ merization behaviors. 24,25 The slightly higher reactivity of 3TFPhMI than of 4TFPhMI, as seen in min. The decomposition temperatures determined are summarized in Table III, together with the Table I and Figure 2, is interpreted as an electronic effect; namely, a para-trifluoromethyl group is a previous results for poly(MPhMI)s. 4 It has been revealed that poly(TFPhMI)s have stronger electron-withdrawing group than that in the meta position.…”

High incidence of cytomegalovirus, human herpesvirus-6, and Epstein-Barr virus reactivation in patients receiving cytotoxic chemotherapy for Adult T cell leukemia

“…Copolymerizations of N‐substituted maleimides with various vinyl monomers have been investigated by many authors 21–27. Specifically, copolymerization with electron‐donor monomers such as styrene is well‐known to yield alternating copolymers, and the copolymerization mechanism has been discussed by others 26–29…”

Thermal, Mechanical, and Optical Properties of Maleimide Copolymers Containing Twisted N‐Phenyl Substituents in the Side Chain

“…When the copolymerization was performed using a large excess amount of VE, the alternating copolymers ( P1a ‐ P1c ) were produced (Scheme ). A difference in the molecular conformation of the N ‐phenyl moieties had no effect on the reactivity during the alternating copolymerization of the RPhMIs with VE under the conditions shown in Table , while it was reported in the literature that the reactivity of the RPhMIs was suppressed by the introduction of bulky alkyl groups into the ortho positions during the homopolymerization and copolymerizations with St and MMA . All the copolymers with VE were revealed to have high onset temperatures for decomposition ( T d5 =342 °C–346 °C) [Figure (a)] and high T g values in the range of 128 °C–151 °C (See Table ).…”