Fate of TDI and MDI in Air, Soil, and Water

Gilbert, Diane

doi:10.1177/0021955x8802400206

Cited by 11 publications

(5 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…DMSO, TEA, and toluene were stored over A4 molecular sieve, The hydrolysis of isocyanates is a topic of strong interest. Due to health and environmental concerns, environmentalists have investigated the fate of commonly used isocyanates in water and soil by studying their hydrolysis kinetics [23]. Both aromatic and aliphatic isocyanates get hydrolyzed in aqueous solutions to their corresponding amines, which readily react with neighboring isocyanates forming a polyurea.…”

Section: Methodsmentioning

confidence: 99%

A Simple Method for the Quantification of Free Isocyanates on the Surface of Cellulose Nanocrystals upon Carbamation using Toluene Diisocyanate

Abushammala

2019

Surfaces

View full text Add to dashboard Cite

In many reports, cellulose and nanocellulose have been carbamated using 2,4-toluene diisocyanate (2,4-TDI) to allow the grafting of molecules or polymers onto their surfaces. Such a process usually involves the reaction of the more reactive isocyanate group of TDI (para-NCO) selectively with a hydroxyl group from the cellulose surface, followed by the reaction of the free isocyanate (ortho-NCO) with a desired molecule. After the first step, it is not possible, using elemental analysis, to determine the amount of ortho-NCO on the cellulosic surface, as an ideal para/ortho selectivity is difficult to obtain. This paper presents a simple method for the quantification of ortho-NCOs on the surface of cellulose nanocrystals upon TDI-based carbamation. It relies on the pH increase upon a complete hydrolysis of ortho-NCOs to amine groups using acidified dimethylsulfoxide. The method was found to be accurate and valid for a degree of substitution of up to 20%.

show abstract

Section: Methodsmentioning

confidence: 99%

A Simple Method for the Quantification of Free Isocyanates on the Surface of Cellulose Nanocrystals upon Carbamation using Toluene Diisocyanate

Abushammala

2019

Surfaces

View full text Add to dashboard Cite

show abstract

“…Polyurethanes form an important group of commercial polymers; approaching 1 million tonnes of toluene diisocyanate (TDI) were sold worldwide in 1988 [12]. Its major application is in the manufacture of¯exible polyurethane foams, which involves the reaction of TDI with polyols in the presence of catalysts (e.g.…”

Section: Introductionmentioning

confidence: 99%

An epidemiology study of lung function changes of toluene diisocyanate foam workers in the United Kingdom

Clark¹,

Bugler²,

McDermott³

et al. 1998

International Archives of Occupational and Environmental Health

View full text Add to dashboard Cite

show abstract

“…On the industrial scale, diisocyanates are usually produced from petroleum resources and, in most cases, they are obtained by reacting a primary amine with highly toxic phosgene [ 70 , 71 ]. The exposure of the natural environment to isocyanates can lead to the pollution of water [ 72 ], soil [ 73 ], and air [ 74 ]. Therefore, the content of pMDI in hybrid resins should be adjusted to be as low as possible to decrease the negative impact and reduce production costs.…”

Section: Resultsmentioning

confidence: 99%

Optimization of Isocyanate Content in PF/pMDI Adhesive for the Production of High-Performing Particleboards

Kawalerczyk,

Dukarska,

Barczewski

et al. 2023

Polymers

View full text Add to dashboard Cite

Due to the fact that impregnation with fire retardant usually reduces the strength of the produced particleboards, this research was carried out to investigate whether it is possible to use phenol–formaldehyde (PF) resin modified using various amounts (0%, 5%, 10%, 15%, and 20%) of polymeric 4,4′-methylene diphenyl diisocyanate (pMDI) for this purpose. The need to optimize the addition of pMDI is particularly important due to health and environmental aspects and high price. Furthermore, the curing process of hybrid resins is still not fully explained, especially in the case of small loadings. Manufactured particleboards differed in the share of impregnated particles (50% and 100%). The mixture of potassium carbonate and urea was used as the impregnating solution. Based on the outcomes of hybrid resins properties, it was found that the addition of pMDI leads to the increase in solid content, pH, and viscosity of the mixtures, to the improvement in resin reactivity determined using differential scanning calorimetry and to the decrease in thermal stability in the cured state evaluated using thermogravimetric analysis. Moreover, particleboard property results have shown that using impregnated particles (both 50% and 100%) decreased the strength of manufactured boards bonded using neat PF resin. However, the introduction of pMDI allowed us to compensate for the negative impact of fire-retardant-treated wood and it was found that the optimal loading of pMDI for the board containing 50% of impregnated particles is 5% and for board made entirely of treated wood it is 10%.

show abstract

Fate of TDI and MDI in Air, Soil, and Water

Cited by 11 publications

References 11 publications

A Simple Method for the Quantification of Free Isocyanates on the Surface of Cellulose Nanocrystals upon Carbamation using Toluene Diisocyanate

A Simple Method for the Quantification of Free Isocyanates on the Surface of Cellulose Nanocrystals upon Carbamation using Toluene Diisocyanate

An epidemiology study of lung function changes of toluene diisocyanate foam workers in the United Kingdom

Optimization of Isocyanate Content in PF/pMDI Adhesive for the Production of High-Performing Particleboards

Contact Info

Product

Resources

About