2,4-Tolylene Diisocyanate (TDI) & Diphenylmethane Diisocyanate (MDI)

Several efforts have been dedicated to the development of lignin-based polyurethanes (PU) in recent years. The low and heterogeneous reactivity of lignin hydroxyl groups towards diisocyanates, arising from their highly complex chemical structure, limits the application of this biopolymer in PU synthesis. Besides the well-known differences in the reactivity of aliphatic and aromatic hydroxyl groups, experimental work in which the reactivity of both types of hydroxyl, especially the aromatic ones present in syringyl (S-unit), guaiacyl (G-unit), and p-hydroxyphenyl (H-unit) building units are considered and compared, is still lacking in the literature. In this work, the hydroxyl reactivity of two kraft lignin grades towards 4,4′-diphenylmethane diisocyanate (MDI) was investigated. 31P NMR allowed the monitoring of the reactivity of each hydroxyl group in the lignin structure. FTIR spectra revealed the evolution of peaks related to hydroxyl consumption and urethane formation. These results might support new PU developments, including the use of unmodified lignin and the synthesis of MDI-functionalized biopolymers or prepolymers.

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Framed aromatic polyurethanes based on an anionic macroinitiator, 4,4'-diphenylmethane diisocyanate, and 4,4'-dihydroxy-2,2-diphenylpropane: Metal-complex modification

Polymer Science Series B ◽

10.1134/s1560090417010055 ◽

2017 ◽

Vol 59 (1) ◽

pp. 69-79

Author(s):

I. M. Davletbaeva ◽

I. I. Zaripov ◽

R. R. Karimullin ◽

A. M. Gumerov ◽

R. S. Davletbaev ◽

...

Keyword(s):

Metal Complex ◽

Diphenylmethane Diisocyanate

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Death due to Asthma at Workplace in a Diphenylmethane Diisocyanate-Sensitized Subject

Respiration ◽

10.1159/000196653 ◽

1997 ◽

Vol 64 (1) ◽

pp. 111-113 ◽

Cited By ~ 39

Author(s):

Mauro Carino ◽

Maria Aliani ◽

Carmelo Licitra ◽

Nicola Sarno ◽

Francesco Ioli

Keyword(s):

Diphenylmethane Diisocyanate

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Synthesis and properties of novel polystyrene/polyurea and functional graphene-based nanocomposite foams

Journal of Cellular Plastics ◽

10.1177/0021955x16652104 ◽

2016 ◽

Vol 53 (3) ◽

pp. 305-318 ◽

Cited By ~ 2

Author(s):

Ayesha Kausar

Keyword(s):

Cellular Structure ◽

Graphene Layer ◽

Decomposition Temperature ◽

Absorption Capacity ◽

Water Absorption Capacity ◽

Diphenylmethane Diisocyanate ◽

Intrinsic Properties ◽

Simple Route ◽

Nanocomposite Foams ◽

Properties Of Materials

A simple route has been adopted for the fabrication of polyurea using polycondensation of 4,4'-diphenylmethane diisocyanate and 1,4-phenylene diamine. Amalgamation of polystyrene, polyurea and functional graphene (F–G) yielded a series of nanocomposite foams. The morphological, electrical, mechanical, thermal, and flammability properties of materials were investigated and found to be dependent upon the intrinsic properties of graphene-based materials and their state of dispersion in matrix. Field emission scanning electron microscopy revealed a strong interaction between polystyrene/polyurea and functional graphene surface forming unique layered cellular structure. Mechanical results revealed a synergistic interaction between F–G and polystyrene/polyurea matrix providing a shielding mechanism against graphene layer damage during compression. The 10% thermal decomposition temperature of polystyrene/polyurea/F–G 1–5 foams measured was in the range of 432–470℃. UL 94 showed V-1 rating for polystyrene/polyurea foam, while polystyrene/polyurea/F–G 1–5 foams attained V-0 rating. Water absorption capacity was improved steadily with the time and was maximum after 96 h for polystyrene/polyurea/F–G 5 foam (4.53%). Functional graphene also produced excellent electrical conductivity improvement in polystyrene/polyurea/F–G 5 foam (101) relative to polystyrene/polyurea/F–G 1 foam (10−2) and neat polystyrene/polyurea foam materials (10−7).

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HPLC Determination of the Isomeric Ratios of Diphenylmethane Diisocyanate in Modified Isocyanates

Journal of Chromatographic Science ◽

10.1093/chromsci/27.5.262 ◽

1989 ◽

Vol 27 (5) ◽

pp. 262-266 ◽

Cited By ~ 2

Author(s):

M. Schreyer ◽

W.- D. Domke ◽

S. Stini

Keyword(s):

Hplc Determination ◽

Diphenylmethane Diisocyanate ◽

Isomeric Ratios

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Aromatic Polybenzimidazoles on the Basis of 4,4′-Diphenylmethane Diisocyanate and Bis(arylene)hydroxamic Acids

Polymer Science Series B ◽

10.1134/s1560090418010050 ◽

2018 ◽

Vol 60 (1) ◽

pp. 16-19 ◽

Cited By ~ 2

Author(s):

M. N. Grigor’eva ◽

D. M. Mognonov ◽

Yu. V. Tonevitskii ◽

S. A. Stel’makh ◽

O. S. Ochirov

Keyword(s):

Hydroxamic Acids ◽

Diphenylmethane Diisocyanate

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METHODS FOR PREPARING MODIFIED LIQUID COMPOSITIONS BASED ON 4,4'-DIPHENYLMETHANE DIISOCYANATE IN THE CONDITIONS OF SMALL-SCALE PRODUCTION

Chemistry and Technology of Organic Substances ◽

10.54468/25876724_2020_2_28 ◽

2020 ◽

pp. 28-47

Author(s):

Galina Mikhailovna Komissarova ◽

Eduard Leonidovich Belyaev ◽

Mikhail Kirillovich Smirnov ◽

Yulia Yurievna Golubeva ◽

Natalia Alexandrovna Pavlova ◽

...

Keyword(s):

Small Scale ◽

Scale Production ◽

Diphenylmethane Diisocyanate

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A Review of the Surface Modification of Cellulose and Nanocellulose Using Aliphatic and Aromatic Mono- and Di-Isocyanates

Molecules ◽

10.3390/molecules24152782 ◽

2019 ◽

Vol 24 (15) ◽

pp. 2782 ◽

Cited By ~ 18

Author(s):

Hatem Abushammala ◽

Jia Mao

Keyword(s):

Surface Modification ◽

Functional Groups ◽

Phenyl Isocyanate ◽

Hexamethylene Diisocyanate ◽

Toluene Diisocyanate ◽

Diphenylmethane Diisocyanate ◽

Chemical Modifications ◽

Advantages And Disadvantages ◽

Wide Range ◽

Simple Molecules

Nanocellulose has been subjected to a wide range of chemical modifications towards increasing its potential in certain fields of interest. These modifications either modulated the chemistry of the nanocellulose itself or introduced certain functional groups onto its surface, which varied from simple molecules to polymers. Among many, aliphatic and aromatic mono- and di-isocyanates are a group of chemicals that have been used for a century to modify cellulose. Despite only being used recently with nanocellulose, they have shown great potential as surface modifiers and chemical linkers to graft certain functional chemicals and polymers onto the nanocellulose surface. This review discusses the modification of cellulose and nanocellulose using isocyanates including phenyl isocyanate (PI), octadecyl isocyanate (OI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HMDI), and their derivatives and polymers. It also presents the most commonly used nanocellulose modification strategies including their advantages and disadvantages. It finally discusses the challenges of using isocyanates, in general, for nanocellulose modification.

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