Infrared thermographic analysis on copolymerization of spiroorthoester with oxetane

Abstract

Infrared (IR) thermography was employed to monitor temperature changes during the copolymerization of a spiroorthoester monomer with an oxetane monomer initiated with a benzyl sulfonium salt. The temperature changes in the polymerizations decreased with the increase of the initial feed ratios of the spiroorthocarbonate monomer. For instance, the temperature in the copolymerization of the equimolar mixture of both of the monomers increased only ∼1 °C, whereas that in the homopolymerization of the oxetane monomer increased more than 20 °C. This result indicates that the copolymerization employing spiroorthocarbonate monomers effectively suppress temperature increase, which are responsible to shrinkage during cooling. The suppression of polymerization shrinkage by spiroorthocarbonate was also confirmed by density measurement of the polymers using a gas pycnometer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1388–1393, 2007.

Synthesis and cationic ring‐opening polymerization of oxetane monomer containing five‐membered cyclic carbonate moiety via highly chemoselective addition of CO2

“…In addition, trialkyl aluminum/H 2 O catalytic system gives polyoxetanes with well‐controlled molecular weights . Oxetane monomers also undergo cationic ring‐opening copolymerization with six‐ or seven‐membered heterocyclic compounds such as tetrahydropyran, ε ‐caprolactone, 1,3,2‐dioxathiepane‐2‐oxide, spiroorthoester, and spiroorthocarbonate . In other ring‐opening copolymerizations, linear aliphatic polycarbonate synthesis by coupling of carbon dioxide (CO 2 ) and oxetane monomers is one of the important process because CO 2 is regarded as a cheap and green C1 resource, which is useful especially for phosgene free processes .…”

“…[45][46][47] In addition, trialkyl aluminum/H 2 O catalytic system gives polyoxetanes with well-controlled molecular weights. 48,49 Oxetane monomers also undergo cationic ring-opening copolymerization with six-or seven-membered heterocyclic compounds such as tetrahydropyran, 50 ε-caprolactone, 51 1,3,2-dioxathiepane-2-oxide, 52 spiroorthoester, 53,54 and spiroorthocarbonate. 55 Additional supporting information may be found in the online version of this article.…”

Novel analytical method for the crosslinking process: Infrared thermographic analysis of the thermally latent cationic polymerization of a spiroorthoester and a bifunctional oxetane for the construction of a low‐shrinkage curing system

“…4 The negligible volume changes are effective for reducing troublesome volume shrinkages in cationic curing systems, including those employing latent initiators to construct facile curing systems. [9][10][11][12][13][14][15][16] For instance, copolymerizations of double ring-opening monomers with conventional curing agents such as epoxides and oxetanes have been developed to construct curing systems with low internal strain. 9,[17][18][19] If one wishes to evaluate a curing system involving crosslinking reactions rapidly, the heterogeneity or insolubility of the products must be taken into account.…”

“…[9][10][11][12][13][14][15][16] For instance, copolymerizations of double ring-opening monomers with conventional curing agents such as epoxides and oxetanes have been developed to construct curing systems with low internal strain. 9,[17][18][19] If one wishes to evaluate a curing system involving crosslinking reactions rapidly, the heterogeneity or insolubility of the products must be taken into account. That is, the evaluation methods should analyze samples, unavailable to typical nuclear magnetic resonance (NMR) spectroscopic or chromatographic analysis, without any treatments (e.g., extraction and crushing).…”

“…One of the efficient screening systems for multiple heterogeneous samples is a noncontact measurement of temperatures in reaction mixtures, which typically rise with the reaction courses. 9,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] Crivello and coworkers [20][21][22][23][24][25][26][27] have established a facile and reproducible analytical method for the photoinitiated polymerization of various monomers. From this point of view, we have preliminarily investigated (co)polymerizations of SOE and oxetane monomers with thermally latent sulfonium salts.…”