First Synthesis of a Polyurethane by Frontal Polymerization

Abstract

The first synthesis of a polyurethane by frontal polymerization has been successfully carried out. Namely, the two reactants (1,6-hexamethylene diisocyanate and ethylene glycol) and the catalyst (dibutyltin dilaurate) were mixed together at room temperature in the presence of an additive (pyrocatechol, necessary for extending pot life), dimethyl sulfoxide (as the solvent), and a filler (fumed silica, added for stabilizing the propagating front). The reactions were thermally ignited at one end of the tubular reactor, and the resultant hot fronts were allowed to self-propagate throughout the reaction vessel. The effects of relative amounts of the above components on the most relevant parameters relating to frontal polymerization (temperature profile, front velocity, and temperature) were thoroughly investigated.

Frontal polymerization as a convenient technique for the consolidation of tuff

“…Since 2000, our research group has been active in this field [20][21][22][23][24][25][26][27][28][29][30]. Namely, we have studied the application of FP to the synthesis of polyurethanes [20,21], polydicyclopentadiene [22], polyacrylates [23], interpenetrating polymer networks composed of polydicyclopentadiene and polyacrylates [24], polyester resins [25,26] and epoxy resins [27].…”

“…Namely, we have studied the application of FP to the synthesis of polyurethanes [20,21], polydicyclopentadiene [22], polyacrylates [23], interpenetrating polymer networks composed of polydicyclopentadiene and polyacrylates [24], polyester resins [25,26] and epoxy resins [27]. Furthermore, polymer nanocomposites containing polyhedral oligomeric silsesquioxanes [28] and montmorillonite [29] as nanofillers were synthesized.…”

Frontal Polymerization Synthesis of Starch‐Grafted Hydrogels: Effect of Temperature and Tube Size on Propagating Front and Properties of Hydrogels

“…[5] The application of FP to synthesize copolymers has been investigated. [6][7][8] Recently, FP was used by Fiori and Mariani for the synthesis of polyurethane, [9] by McFarland and Pojman for the polymerization of 1,6-hexanediol diacrylate with a microencapsulated initiator. [10] In these examples, the rapid reaction rate, observed in propagating fronts, circumvents phase separation which occurs commonly in batch studies.…”

“…In all previous works on FP a number of aspects have been explored, such as the effect of initiator type and concentration on front velocity [10,12,13] and the effect of pressure [14] and tube orientation, [15] the dependences of front velocity and front temperature on reaction components. [9,11] In fact FP is performed in a nonadiabatic reactor under the atmosphere in order to test the applicability of this technique to process conditions often found in practice. Thus the environmental conditions such as temperature and reactor size are the key factors for the formation and traveling behavior of self-propagating thermal front [13,16] and the consequent material properties.…”

Frontal atom transfer radical polymerization of tri(ethylene glycol) dimethacrylate

“…In particular, the following have been studied: frontal ring opening metathesis polymerization (FROMP) of dicyclopentadiene [11]; the synthesis of polyurethanes [12,13]; the curing of polyester-styrene resins [14]; the production of interpenetrating polymer networks composed of polydicyclopentadiene and polyacrylates [15]; and the consolidation and protection of porous materials (stone, wood, textiles) with applications in the artistic-historical field [16].…”