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DIPHENYL THIOUREA | ||
PRODUCT IDENTIFICATION |
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CAS NO | 102-08-9 | |
EINECS NO. | 203-004-2 | |
FORMULA | CS(NHC6H5)2 | |
MOL WT. | 228.31 | |
H.S. CODE |
2930.90 |
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TOXICITY |
Oral rat LD50; 50 mg/kg | |
SYNONYMS | 1,3-diphenyl-2-thiourea; DPTU; | |
1,3-diphenylthiourea; N,N'-diphenylthiocarbamide; Thiocarbanilide; | ||
N,N'-Diphenylthiourea; Sulfocarbanilide; sym-Diphenylthiourea; n,n'-Diphenylthioharnstoff (Dutch),n,n'-Diphénylthiourée (French), n,n'-Difeniltiourea (Spanish); | ||
RAW MATERIALS | ||
CLASSIFICATION |
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PHYSICAL AND CHEMICAL PROPERTIES |
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PHYSICAL STATE | White to pale pink powder | |
MELTING POINT |
148 - 155 C | |
BOILING POINT | ||
SPECIFIC GRAVITY | 1.32 | |
SOLUBILITY IN WATER |
Insoluble (soluble in alcohol and ether) | |
pH | ||
VAPOR DENSITY | ||
AUTOIGNITION |
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REFRACTIVE INDEX |
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NFPA RATINGS | ||
FLASH POINT |
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STABILITY | Stable under ordinary conditions | |
GENERAL DESCRIPTION & APPLICATIONS |
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Sulfur combines with nearly all elements. Sulfur forms ring and chain structures
as it is the second only to carbon in exhibiting catenation. The 8-membered ring and
shorter chain structure of sulfur molecule is important in vulcanization
process which individual polymers are linked to other polymer molecules by
atomic bridges. This process produces thermoset materials which are cross-linked
and irreversible substances. The term thermoplastic is for high molecular weight
polymers which can undergo melting-freezing cycle. Thermosets are not melted and
re-molded on heating after cured. The split of sulfur 8-membered ring structure into shorter chains provides rubber vulcanization process. The split are
liked with cure sites (some of the solid bonds in the molecule) on rubber
molecules, resulting in forming sulfur bridges typically between 2 and 10 atoms
long. Vulcanization makes rubber harder, more durable and more resistant to
heating, aging and chemical attacks. The number of sulfur atoms in the sulfur bridges varies physical properties of
the end products. Short bridges containing one or two sulfur atoms offer heat
resistance and long bridges offer flexible property. Vulcanization can also be accomplished with
certain peroxides, gamma radiation, and several other organic compounds. The
principal classes of peroxide cross-linking agents are dialkyl and diaralkyl
peroxides, peroxyketals and peroxyesters. Other vulcanizing agents include amine
compounds for the cross-linking of fluorocarbon rubbers, metal oxides for
chlorine-containing rubbers (notably zinc oxide for chloroprene rubber) and
phenol-formaldehyde resins for the production of heat-resistant butyl rubber
vulcanizates. Accelerator, in the rubber industry, is added with a curing agent
to speed the vulcanization. Accelerators contain sulfur and nitrogen like derivatives of benzothiazole and thiocarbanilides.
The popular accelerators are
sulfenamides (as a delayed-action accelerators), thiazoles, thiuram sulfides,
dithocarbamates and guanidines.
There are some types of rubber accelerators. They are used in combination with each other in accordance with vulcanizing and/or acid-base conditions. Some examples classified by chemical structure are as below;
Diphenyl Thiourea is used as a primary or secondary vulcanization accelerator. It is used as an intermediate for the synthesis of dye and other organic compounds. It is used as an ore flotation agent. |
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SALES SPECIFICATION | ||
APPEARANCE |
White powder | |
ACTIVE CONTENT |
96.0% min | |
MELTING POINT |
148 C min | |
ASH |
0.3% max | |
HEAT LOSS |
0.3% max | |
FINENESS |
99.9% (150 mesh) | |
TRANSPORTATION | ||
PACKING | 25kgs in Bag | |
HAZARD CLASS | 6.1 (Packing Group: II) | |
UN NO. | 2811 | |
GENERAL DESCRIPTION OF THIOUREA |
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Thiourea (also called Thiocarbamide or Sulfourea) is the diamide of thiocarbonic acid that resembles urea but contains sulfur instead of oxygen. 'Thio' is a chemical prefix indicates the replacement of an oxygen in an acid radical by sulfur with a negative valence of 2; meaning 'Sulfur' derived from the Greek theion. In fct, thiourea occurs as the mixture of two tautomers: S=C(NH2)2 ( Thiourea) + HS=CNHNH2 (Isothiourea), accordingly, provides three functional groups (mino, imino, and thiol). Thiourea is a lustrous white crystalline compound; estimated melting point is 170-180 C; soluble in water and in polar organic solvents; insoluble in non-polar solvents. The exact melting point and boiling point are not available since rearrangement to ammonium thiocyanate (NH4SCN) occurs at about 135 C and decomposition occurs. It can be prepared by heating ammonium thiocyanate, or by the addition of hydrogen sulfide to cyanamide. The latter is the more common method. Thiourea is used directly in ore filtering, metal refinery and cleaning, isomerization catalyst (conversion of maleic to fumaric acid) and as an additive in fertilizers (to inhibit the nitrification process), drilling auxiliaries, light-sensitive photocopy paper and explosives. It is used as a fixing agent in photography, as a liquefying agent in animal hide glue, as an insecticide, as a textile-treating agent, and as an intermediate to produce other compounds. Thiourea and its derivatives are versatile intermediates for the synthesis of modified thermosetting resins, thiourea dioxide, dyes, flame retardants, vulcanization accelerators, plant protection agents, pesticides, amino resins, peptizing agents, fungicides, hair preparations, dry cleaning chemicals, corrosion inhibitors and thiazole drugs (e.g., antiseptic, thyrotherapeutic, narcotic, and tuberculostatic agents). Dithiobiurea possesses a wide dipole moment and thus is involved in the forming wide metal chelated complexes as the radioactiv-compound which used in radiopharmaceutical imaging, inhibiting enzyme function, kidney function study and to treat toxic metal poisoning. It is used in co-crystals development used in the field of nonlinear optics to generate new coherent wavelengths. |
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