Remarkable Change in Fluorescence Emission of Poly(diphenylacetylene) Film via in situ Desilylation Reaction: Correlation with Variations in Microporous Structure, Chain Conformation, and Lamellar Layer Distance

Abstract

Fluorescence (FL) emission properties, microporous structures, energy-minimized chain conformations, and lamellar layer structures of the silicon-containing poly(diphenylacetylene) derivative of p-PTMSDPA before and after desilylation were investigated. The nitrogen-adsorption isotherms of p-PTMSDPA film before and after desilylation were typical of type I, indicating microporous structures. The BET surface area and pore volume of the p-PTMSDPA film were significantly reduced after the desilylation reaction, simultaneously, its FL emission intensity remarkably decreased. The theoretical calculation on both model compounds of p-PTMSDPA and its desilylated polymer, PDPA, showed a remarkable difference in chain conformation: The side phenyl rings of p-PTMSDPA are discontinuously arranged in a zig-zag pattern, while the PDPA is continuously coiled in a helical manner. The lamellar layer distance (LLD) in the p-PTMSDPA film significantly decreased after the desilylation reaction.

Conjugated Polymers of Intrinsic Microporosity (C‐PIMs)

“…We also synthesized a further range of linear conjugated polymers ( M–R ), derived from di‐ and mono‐substituted acetylene. These are based on the known conjugated polymer, poly[1‐phenyl‐2‐( p ‐trimethylsilyl)phenylacetylene], which was previously demonstrated to be porous …”

Phase-change hybrids for thermo-responsive sensors and actuators

“…From many PDPA derivatives, poly[1-phenyl-2-(p-trimethylsilyl) phenylacetylene] (PDPA C1 in Figure 1) was selected as the matrix because this material is a strongly fluorescent polymer with an extremely large fractional free volume (40.26) 27 (BET surface area: 635 m 2 g − 1 ; total pore volume: 0.36 cm 3 g -1 ). 46 The PDPA C1 used in this study had a relatively high average molecular weight (M w = 1.34 × 10 6 g mol -1 ) with a narrow polydispersity index…”

Fluorescent Actuator Based on Microporous Conjugated Polymer with Intramolecular Stack Structure

“…In the swollen state, this polymer exhibited excellent fl uorescence (FL) responses to chemical stimuli. [ 6 ] Various chemicals, such as alcohols, hydrocarbons, and silicon oils, readily diffused into the PTMSDPA fi lm through the many microvoids (FFV: > 0.26 [ 7 ] ; BET surface area: 635 m 2 g − 1 ; Total pore volume: 0.36 cm 3 g − 1 in fi lm [ 8 ] ) to immediately expand the polymer chains, simultaneously leading to signifi cant enhancement of FL emission due to relaxation of the intramolecular stack structure of bulky side phenyl rings. [ 6c , 9 ] However, its functionality as an actuator has never been explored, as it was usually deposited on glass substrates.…”