Identifying competitive tin- or metal-free catalyst combinations to tailor polyurethane prepolymer and network properties

Arnould, Priscilla; Bosco, Lionel; Sanz, F.; Simon, Frédéric; Fouquay, Stéphane; Michaud, Guillaume; Raynaud, Jean; Monteil, Vincent

doi:10.1039/d0py00864h

Cited by 18 publications

(38 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such higher conversions of the bismuth triflate can be related to its activity towards both the gelling and blowing reactions, since it has a high Lewis acidity and is soluble in water. A previous study by Arnould et al showed similar catalytic efficiency of bismuth neodecanoate compared to a Sn catalyst, in particular dioctyltin dilaurate [34]. Meanwhile, Levent et al showed only moderate activity of several bismuth carboxylates towards the isocyanate/alcohol reaction, but that it can be improved using heterobimetallic complexes with lithium carboxylate [20].…”

Section: Resultsmentioning

confidence: 97%

Use of Novel Non-Toxic Bismuth Catalyst for the Preparation of Flexible Polyurethane Foam

et al. 2021

View full text Add to dashboard Cite

Foam products are one of the largest markets for polyurethane (PU) and are heavily used in many sectors. However, current PU formulations use highly toxic and environmentally unfriendly production processes. Meanwhile, the increasing environmental concerns and regulations are intensifying the research into green and non-toxic products. In this study, we synthesized flexible polyurethane foam (PUF) using different weight percentages (0.025%, 0.05% and 0.1%) of a non-toxic bismuth catalyst. The bismuth-catalyzed foams presented a well evolved cellular structure with an open cell morphology. The properties of the bismuth-catalyzed flexible PUF, such as the mechanical, morphological, kinetic and thermal behaviors, were optimized and compared with a conventional tin-catalyzed PUF. The bismuth-catalyst revealed a higher isocyanate conversion efficiency than the stannous octoate catalyst. When comparing samples with similar densities, the bismuth-catalyzed foams present better mechanical behavior than the tin-catalyzed sample with similar thermal stability. The high solubility of bismuth triflate in water, together with its high Lewis acidity, have been shown to benefit the production of PU foams.

show abstract

Section: Resultsmentioning

confidence: 97%

Use of Novel Non-Toxic Bismuth Catalyst for the Preparation of Flexible Polyurethane Foam

et al. 2021

View full text Add to dashboard Cite

show abstract

“…[5][6][7] Therefore, one of the main development trends in PU synthesis is finding improved catalysts. 8 Although the isocyanate-hydroxyl reaction can be catalysed by several types of compounds, [9][10][11][12][13] the most prevalent ones used in the manufacturing processes are organotins 14 and tertiary amines. 15 The kinetics and mechanism of the tertiary amine catalysed isocyanate-alcohol reactions have been the subject of several research studies.…”

Section: Introductionmentioning

confidence: 99%

“…5–7 Therefore, one of the main development trends in PU synthesis is finding improved catalysts. 8 Although the isocyanate–hydroxyl reaction can be catalysed by several types of compounds, 9–13 the most prevalent ones used in the manufacturing processes are organotins 14 and tertiary amines. 15…”

Section: Introductionmentioning

confidence: 99%

Aliphatic tertiary amine catalysed urethane formation – a combined experimental and theoretical study

Waleed

Csécsi

Konyhas

et al. 2022

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…To this end, more ecofriendly catalysts have been stud-ied to replace standard tin catalysts with either metallic catalysts based on sustainable metals such as titanium, iron, copper and zinc, or organocatalysts such as nitrogen-centered Lewis bases (amines, guanidines and amidines…). [8][9][10][11][12][13][14][15][16] Among aliphatic diisocyanate monomers, isophorone diisocyanate (IPDI) is the most promising candidate since the volatility of HDI precludes its widespread use. IPDI is an asymmetrical diisocyanate, owning a primary aliphatic and a secondary cycloaliphatic isocyanate functions with two uneven intrinsic reactivities.…”

Section: Introductionmentioning

confidence: 99%

“…To this end, more ecofriendly catalysts have been studied to replace standard Sn catalysts with either metallic catalysts based on sustainable metals, such as titanium, iron, copper, and zinc, or organocatalysts such as nitrogen-centered Lewis bases (amines, guanidines, amidines, etc. ). − …”

Section: Introductionmentioning

confidence: 99%

Harnessing Catalysis Selectivity and Isophorone Diisocyanate Asymmetry for Tailored Polyurethane Prepolymers and Networks

Arnould

Simon²,

Fouquay³

et al. 2022

Macromolecules

Self Cite

View full text Add to dashboard Cite

We synthesized polyurethane materials via a typical industrial two-stage process based on the synthesis of NCO-terminated prepolymers followed by their crosslinking with polyols. We investigated the influence of metallic and organic catalysts on i) polyaddition kinetics between a challenging monomer (the aliphatic and asymmetric isophorone diisocyanate a.k.a. IPDI) and polyols, and on ii) the structure and properties of corresponding polyurethane prepolymers and networks. Tin-free catalysts (Ti, Zn-based) and even metal-free catalysts (guanidines, amidines, amines) are competitive alternatives to a standard tin catalyst. Beside the activity criterion, appropriately choosing the catalyst allows to adjust the prepolymer structure relying on respective selectivities toward primary vs. secondary isocyanate moieties, as well as propensity to favor functionalization over chain extension. By quantitative NMR spectroscopy, three different catalyst selectivities are pinpointed, which either favor the primary or the secondary isocyanate functions or promote their isoreactivity. These selectivities are harnessed both at the prepolymerization and crosslinking stages to significantly decrease reaction time by judicious and innovative combinations of catalysts with opposite selectivities toward primary/secondary isocyanates. We eventually evidenced the efficiency of this methodology for tailored polyurethane-based materials through in-situ solid-state NMR monitoring of the crosslinking stage.

show abstract

Identifying competitive tin- or metal-free catalyst combinations to tailor polyurethane prepolymer and network properties

Abstract: The influences of selected catalysts on the structures and properties of polyurethane prepolymers and networks are investigated to adjust the catalyst/structure/properties relationship to a targeted application. This study highlights the...

Cited by 18 publications

References 30 publications

Use of Novel Non-Toxic Bismuth Catalyst for the Preparation of Flexible Polyurethane Foam

Use of Novel Non-Toxic Bismuth Catalyst for the Preparation of Flexible Polyurethane Foam

Aliphatic tertiary amine catalysed urethane formation – a combined experimental and theoretical study

Harnessing Catalysis Selectivity and Isophorone Diisocyanate Asymmetry for Tailored Polyurethane Prepolymers and Networks

Contact Info

Product

Resources

About