108-78-1 Usage
Description
Melamine-formaldehyde resin (MFR) is an active
ingredient of strong (reinforced) plasters. Sensitization
was reported in a plaster-room technician, who applied
resin-reinforced pIaster casts, and in dental technicians.
MFR was contained in a strong dental pIaster
used for mouldings. Used as a textile finish res in, it was
also found to be an allergen in a women who replaced
clothes in a store. MFR also releases formaldehyde,
which may be the sensitizer.
Chemical Properties
Different sources of media describe the Chemical Properties of 108-78-1 differently. You can refer to the following data:
1. White Solid
2. Melamine is a white crystalline solid
Uses
Different sources of media describe the Uses of 108-78-1 differently. You can refer to the following data:
1. A compound that forms synthetic resins with formaldehyde
2. Forms synthetic resins with formaldehyde.
3. It is used to make high-pressure laminating resins
(e.g., decorative countertops), molded compounds (e.g.,
dinnerware), and surface coating resins (e.g., appliance
finishes and automotive topcoats). Additional major products
are textile and paper treatment resins. Miscellaneous uses
include adhesive resins for gluing lumber, plywood, and
flooring, and resins for leather tanning agents. Melamine,
melamine cyanurate, other melamine salts, and guanidine
compounds are currently the most used group of nitrogencontaining
flame retardants. Melamine is used as a flame
retardant additive for polypropylene and polyethylene.
Melamine cyanurate is employed commercially as a flame
retardant for polyamides and terephthalates.
Production Methods
Different sources of media describe the Production Methods of 108-78-1 differently. You can refer to the following data:
1. The compound now is synthesized from urea.
2. Melamine is prepared almost exclusively by the urea
process—the action of ammonia on urea. It is produced
worldwide.
Preparation
The standard route to melamine is from urea. Urea is
heated in the presence of ammonia at 250-350°C and 4--20 MPa. The
reaction probably involves the simultaneous dehydration and hydration of
urea to form cyanamide and ammonium carbamate; trimerization of the
cyanamide then leads to melamine:Thus only 50% of the urea used gives melamine in one step and ammonium
carbamate has to be separated and converted to urea for recycling. Despite
this limitation, the urea route is the most economical of currently available
routes.
Definition
Different sources of media describe the Definition of 108-78-1 differently. You can refer to the following data:
1. ChEBI: A trimer of cyanamide, with a 1,3,5-triazine skeleton.
2. A white solid organic compound
whose molecules consist of a sixmembered
heterocyclic ring of alternate
carbon and nitrogen atoms with three
amino groups attached to the carbons.
Condensation polymerization with
methanal or other aldehydes produces
melamine resins, which are important thermosetting
plastics.
3. melamine: A white crystalline compound,C3N6H6. Melamine is a cycliccompound having a six-memberedring of alternating C and N atoms,with three NH2 groups. It can becopolymerized with methanal to givethermosetting melamine resins,which are used particularly for laminatedcoatings.
General Description
Colorless to white monoclinic crystals or prisms or white powder. Sublimes when gently heated.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Melamine is incompatible with strong oxidizing agents and strong acids . Neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides.
Hazard
Toxic by ingestion, skin, and eye irritant.
Questionable carcinogen.
Fire Hazard
Literature sources indicate that Melamine is nonflammable.
Flammability and Explosibility
Nonflammable
Contact allergens
Melamine-formaldehyde resin (MFR) results from condensation of melamine and formaldehyde. It is anactive ingredient of strong (reinforced) plasters, such as industrial or some dental plasters used for molding.It is also used as a textile finish resin. MFR acts as an allergen generally because of formaldehyde releasing (see Chap. 40)
Safety Profile
Moderately toxic by
ingestion and intraperitoneal routes. An eye,
skin, and mucous membrane irritant. Causes
dermatitis in humans. Questionable
carcinogen with experimental carcinogenic
and tumorigenic data. Experimental
reproductive effects. Mutation data
reported. When heated to decomposition it
emits toxic fumes of NOx and CN-.
Potential Exposure
Manufactured from urea, melamine
is used in the manufacture of plastics, melamineformaldehyde resins; rubber, synthetic textiles; laminates,
adhesives, and molding compound
Carcinogenicity
A bioassay of melamine was
conducted in rats and mice by NTP. Male F344 rats and
B6C3F1 mice were administered melamine in their diets at
concentrations of 2250 or 4500 ppm daily for 103 weeks.Female rats were fed 4500 or 9000 ppm melamine. At the end
of 111 weeks, surviving animals were killed and examined.
Purification Methods
Crystallise Melamine from water or dilute aqueous NaOH. It sublimes at ~240o on prolonged heating. [Beilstein 26 I 74, 26 II 132, 26 III/IV 1253.]
Incompatibilities
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides. Melamine neutralizes
acids in exothermic reactions to form salts plus water. May
be incompatible with isocyanates, halogenated organics,
peroxides, phenols (acidic), epoxides, anhydrides, and acid
halides. Flammable gaseous hydrogen may be generated in
combination with strong reducing agents such as hydrides,
nitrides, alkali metals, and sulfides.
Check Digit Verification of cas no
The CAS Registry Mumber 108-78-1 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 1,0 and 8 respectively; the second part has 2 digits, 7 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 108-78:
(5*1)+(4*0)+(3*8)+(2*7)+(1*8)=51
51 % 10 = 1
So 108-78-1 is a valid CAS Registry Number.
InChI:InChI=1/C3H8N6/c4-2-1-3(5)8-9(6)7-2/h1,7H,4,6H2,(H2,5,8)
108-78-1Relevant articles and documents
-
Schmidt
, p. 664 (1968)
-
-
Henry
, p. 1973 (1966)
-
-
Blair,Braham
, p. 2350 (1922)
-
-
Chastellain
, p. 1298 (1935)
-
Promoting condensation kinetics of polymeric carbon nitride for enhanced photocatalytic activities
Ni, Dongya,Zhang, Yuye,Shen, Yanfei,Liu, Songqin,Zhang, Yuanjian
, (2019)
Polymeric carbon nitride (CN) semiconductor by thermal condensation of N-rich precursors has attracted much attention for its capability ranging from photocatalytic and photoelectrochemical energy conversion to biosensing. However, the influence of condensation process on the final structure of CN was rarely studied, making the condensation kinetic far from be fully optimized. Herein, we report the preparation of CN by a simple condensation kinetics modulation using a faster ramping rate during the polymerization process. The modified condensation recipe was even simpler than the conventional one, but led to an improved photocatalytic H2 evolution up to 3 times without any additional chemicals or other complements. Detailed mechanism studies revealed the increase of crystallinity and surface area due to the rapid condensation played the key roles. This work would offer a more facile and effective way to prepare bulk CN for large-scale industrial applications of bulk CN with higher photocatalytic actives for sustainable energy, environmental and biosensing.
-
Shirai,Sugino
, p. 1046 (1960)
-
-
Kawasaki, A.,Ogata, Y.
, p. 1267 - 1274 (1966)
-
Studies of Cyanamide Derivatives. Part 110. A facile Synthesis of 2,4,6-Triureido-1,3,5-triazine and 2-Amino-4,6-diureido-1,3,5-triazine
Iio, Kokoro,Ichikawa, Eiichi
, p. 2009 - 2010 (1984)
2,4,6-Triureido-1,3,5-triazine and 2-amino-4,6-diureido-1,3,5-triazine were readily synthetized in high yields, 94 and 85percent respectively, by the alcoholysis of 2,4,6-tris(cyanoamino)-1,3,5-triazine and 2-amino-4,6-bis(cyanoamino)-1,3,5-triazine in the presence of hydrogen chloride
Dramatic visible photocatalytic performance of g-C3N4-based nanocomposite due to the synergistic effect of AgBr and ZnO semiconductors
Boorboor Azimi, Elham,Badiei, Alireza,Hossaini Sadr, Moayad
, p. 174 - 183 (2018)
In this study, we synthesized a novel visible-light-driven photocatalyst with excellent photocatalytic activity, g-C3N4/AgBr/ZnO, as a ternary nanocomposite for pollutant degradation via a facile method. This coupling was favorable due to charge transfer between the semiconductors to yield a Z-scheme photocatalysis system, and thus the separation of photo-excited electron–holes was improved. The structure, morphology, and optical properties of the photocatalyst were determined by using characterization techniques, including X-ray diffraction, transmission electron microscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy and its elemental mapping, N2 adsorption-desorption analysis, ultraviolet-visible diffuse reflectance spectroscopy, photoluminescence, fourier transform infrared spectra, and zeta potential measurements. The photocatalytic activity of the g-C3N4/AgBr/ZnO heterostructure was evaluated with different weight ratios during the degradation of the cationic pollutant methylene blue (MB) under exposure to visible light. The optimal photocatalyst with a g-C3N4 content of 30% exhibited superior activity during the degradation of MB and the rate constant of 0.041 min?1 was about 4.6 times higher than the rate constant of the pure g-C3N4. In addition, we assessed the photosensitization of MB and its effect on the photodegradation process. We propose a possible mechanism to explain the photocatalytic activity of the prepared ternary nanocomposite based on experiments with reactive species scavengers. Finally, the reusability and stability of the photocatalyst was investigated after four cycles.
Prebiotic Origin of Pre-RNA Building Blocks in a Urea “Warm Little Pond” Scenario
Menor Salván,Bouza, Marcos,Fialho, David M.,Burcar, Bradley T.,Fernández, Facundo M.,Hud, Nicholas V.
, p. 3504 - 3510 (2020/10/02)
Urea appears to be a key intermediate of important prebiotic synthetic pathways. Concentrated pools of urea likely existed on the surface of the early Earth, as urea is synthesized in significant quantities from hydrogen cyanide or cyanamide (widely accepted prebiotic molecules), it has extremely high water solubility, and it can concentrate to form eutectics from aqueous solutions. We propose a model for the origin of a variety of canonical and non-canonical nucleobases, including some known to form supramolecular assemblies that contain Watson-Crick-like base pairs.The dual nucleophilic-electrophilic character of urea makes it an ideal precursor for the formation of nitrogenous heterocycles. We propose a model for the origin of a variety of canonical and noncanonical nucleobases, including some known to form supramolecular assemblies that contain Watson-Crick-like base pairs. These reactions involve urea condensation with other prebiotic molecules (e. g., malonic acid) that could be driven by environmental cycles (e. g., freezing/thawing, drying/wetting). The resulting heterocycle assemblies are compatible with the formation of nucleosides and, possibly, the chemical evolution of molecular precursors to RNA. We show that urea eutectics at moderate temperature represent a robust prebiotic source of nitrogenous heterocycles. The simplicity of these pathways, and their independence from specific or rare geological events, support the idea of urea being of fundamental importance to the prebiotic chemistry that gave rise to life on Earth.
