Polynorbornene Dicarboximides with Cyclic Pendant Groups: Synthesis and Gas Transport Properties

Abstract

Summary: The synthesis of new N‐cyclopentyl‐exo,endo‐norbornene‐5,6‐dicarboximide (CpNDI) (3a) and N‐cyclohexyl‐exo,endo‐norbornene‐5,6‐dicarboximide (ChNDI) (3b) monomers was carried out. From these monomers, two polynorbornene dicarboximides with cyclopentyl and cyclohexyl pendant groups, poly(exo,endo‐N‐cyclopentyl norbornene‐5,6‐dicarboximide) (PCpNDI) and poly(exo,endo‐N‐cyclohexyl norbonene‐5,6‐dicarboximide) (PChNDI), respectively, were synthesized by ring opening metathesis polymerization (ROMP). PCpNDI, which bears a cyclic pentyl moiety, shows a higher Tg and mechanical properties compared to PChNDI. A comparison of density, fractional free volume, and gas permeability coefficients of the synthesized polynorbornenes shows that PCpNDI presents a slightly higher density and lower fractional free volume than PChNDI. It was also found that gas permeability coefficients for PCpNDI are lower than those of PChNDI. In all cases, the selectivity followed the usual trade‐off found in other glassy polymers: as gas permeability coefficients increase selectivity decreases.Poly(exo,endo‐N‐cyclopentyl norbornene‐5,6‐dicarboximide) (PCpNDI) was synthesized here by ROMP.magnified imagePoly(exo,endo‐N‐cyclopentyl norbornene‐5,6‐dicarboximide) (PCpNDI) was synthesized here by ROMP.

The effect of fluorine atoms on gas transport properties of new polynorbornene dicarboximides

“…It is important to note that low intermolecular and intramolecular interactions in fluorine containing polymers are important factor for gas permeability properties of membranes. Thus, we have already reported gas transport properties of polynorbornenes containing adamantyl, cyclohexyl and cyclopentyl imide side chain groups [1][2][3][4][5]. These glassy polynorbornene dicarboximides showed high T g and good physical and mechanical properties.…”

Norbornene Polymers as Materials for Membrane Gas Separation

“…Another interesting group of MPNB was studied by Mexican researchers [9,[24][25][26]. These authors prepared MPNB by polymerization of N-substituted exo-norbornene-5,6-dicarboximides.…”

“…Gas permeability coefficients P, Barrer of polynorbornenes (PNBs) and poly(trimethylsilyl norbornenes) (PTMSNBs) with different microstructure[21,22] Table 6Transport properties of MPNB with dicarboximide moiety substituted by various groups[24][25][26] …”

“…Separation factors ij ¼ P i /P j of MPNB with dicarboximide moiety substituted by various groups[24][25][26] …”

Synthesis and Ring‐Opening Metathesis Polymerization of New Oxanorbornene Dicarboximides with Fluorine Pendant Groups

“…[1][2][3][4][5][6] We recently proceeded with the synthesis of new poly(norbornene dicarboximide)s by ROMP of exo-N-(1-adamantyl)-norbornene-5,6-dicarboximide and exo-endo-N-cyclohexyl-(cyclopentyl)-norbornene-5,6-dicarboximides using welldefined ruthenium alkylidene (vinylidene) catalysts. [7][8][9] The carboximide-functionalized polynorbornenes showed high T g s, good mechanical properties, and high thermal resistance. [4,7,8] The membranes prepared from early synthesized poly(norbornene dicarboximide)s exhibit rather high permselectivity for the separation of hydrogen from nitrogen, carbon monoxide, methane, and ethylene.…”