Pure gas and hydrocarbon vapor transport properties of blends of two glassy, polyacetylene‐based polymers, poly(1‐trimethylsilyl‐1‐propyne) [PTMSP] and poly(1‐phenyl‐1‐propyne) [PPP], have been determined. Solid‐state CP/MAS NMR proton rotating frame relaxation times were determined in the pure polymers and the blends. NMR studies show that PTMSP and PPP form strongly phase‐separated blends. The permeabilities of the pure polymers and each blend were determined with hydrogen, nitrogen, oxygen, carbon dioxide, and n‐butane. PTMSP exhibits unusual gas and vapor transport properties which result from its extremely high free volume. PTMSP is more permeable to large organic vapors, such as n‐butane, than to small, permanent gases, such as hydrogen. PPP exhibits gas permeation characteristics of conventional low free volume glassy polymers; PPP is more permeable to hydrogen than to n‐butane. In PTMSP/PPP blends, both n‐butane permeability and n‐butane/hydrogen selectivity increase as the PTMSP content of the blends increases. © 1996 John Wiley & Sons, Inc.

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The one-step synthetic strategy for the preparation of the hitherto unknown calix[3]carbazole from readily available starting materials is described. Calix[3]carbazole is obtained in 20% yield, and it could selectively bind the N(C2H5)4(+) cation (tetraethylammonium, TEA) via cation-π interactions. The experimental and modeling results indicate that calix[3]carbazole possesses a larger π-cavity as well as a better chromophoric property than the traditional phenol-based macrocycles, and thus is capable of binding to and optically responding to the relatively large guest TEA.

This research suggests that aliphatic PEG polymers can be used as a new method for increasing the activity of insecticidal proteins.

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