BORAZINE Property

Melting point:

-58°

Boiling point:

55°C

Density 

d40 0.824; d457 0.898

refractive index 

nD20 1.3821

storage temp. 

below 5° C

solubility 

reacts with H2O

pka

-2.66±0.20(Predicted)

form 

colorless liquid

color 

colorless

Specific Gravity

0.81

Water Solubility 

hydrolyzes, evolving boron hydrides [HAW93]

Hydrolytic Sensitivity

9: reacts extremely rapidly with atmospheric moisture - may be pyrophoric - glove box or sealed system required

CAS DataBase Reference

6569-51-3

Safety

Risk Statements 

15-34

Safety Statements 

7-23-26-36-43

RIDADR 

1992

TSCA 

No

HazardClass 

3.1

PackingGroup 

II

HS Code 

28459000

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H225Highly Flammable liquid and vapour

H260In contact with water releases flammable gases which may ignite spontaneously

H314Causes severe skin burns and eye damage

H318Causes serious eye damage

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P223Keep away from any possible contact with water, because of violent reaction and possible flash fire.

P231+P232Handle under inert gas. Protect from moisture.

P233Keep container tightly closed.

P240Ground/bond container and receiving equipment.

P241Use explosion-proof electrical/ventilating/lighting/…/equipment.

P242Use only non-sparking tools.

P243Take precautionary measures against static discharge.

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

P321Specific treatment (see … on this label).

P335+P334Brush off loose particles from skin. Immerse in cool water/wrap in wet bandages.

P363Wash contaminated clothing before reuse.

P370+P378In case of fire: Use … for extinction.

P402+P404Store in a dry place. Store in a closed container.

P403+P235Store in a well-ventilated place. Keep cool.

P405Store locked up.

P501Dispose of contents/container to..…

BORAZINE Chemical Properties,Usage,Production

Description

Borazole (borazine) is a colourless liquid with an aromatic smell. With water, it decomposes to form boric acid, ammonia, and hydrogen. The reaction product of boron and ammonia at high temperatures is also known as inorganic benzene.

Chemical Properties

inorganic analog of benzene; colorless liquid; preparation: heating equimolar mixture of ammonia and BH3 at 250°C–300°C for 30min [MER06] [HAW93]

Uses

Borazine can be useful in the study of structural stability and the low-lying singlet and triplet states of BN - n -acenes, n = 1-7.

Application

Films that were deposited thermally from borazine vapor were found to be too reactive to be suitable for fabricating masks for X-ray lithography. However, films containing predominately cubic boron nitride, CBN [10043-11-5], were deposited using ions extracted from a borazine plasma via an ion beam. Very hard, adherent films were deposited on ceramic, glass, stainless steel, etc. An obvious practical application is the hardening of tool surfaces to markedly extend their life. A thermally deposited film of hexagonal BN [10043-11-5], from B3N3Cl6 [19087-72-0] at 900 ℃, protected SiO2 tubes from halide corrosion. A copolymer between 2,4,6-tributylborazine [7325-06-6] and an unsaturated N,N'-hexamethylenebiscarboxamide was useful for hardening epoxy resins. Trichloroborazine was used as part of a catalyst mix for the polymerization of propene. Flexible BN coatings on copper or copperbase alloys were formed from gaseous 2,4,6- trichloroborazine. The films were stable to 700℃ in air.

Preparation

Borazine was discovered when a mixture consisting of B3H6 and NH3 (or the addition product B3H6-NH3) was heated in a sealed tube. It can also be produced by pyrolysis of a mixture of LiBH4 and NH4Cl. The best yield is obtained by reducing (ClBNH)3  with LiBH4 in n-butyl ether. This reaction also yields B2H6.

General Description

Borazine can be prepared by copyrolysis of NaBH4 and NH4Cl in a highboiling glyme, by reduction of trichloroborazine, or by pyrolysis of ammonia borane in diglyme.
A large body of literature exists on the preparation and chemistry of symmetrically and unsymmetrically substituted borazines. B-Substituted trihaloborazines, readily prepared from BX3 and NH4Cl, react with Grignard reagents to give symmetrical trialkyl- or triarylborazines. Symmetrically substituted N-trialkylor N-triarylborazines are readily prepared from LiBH4 and RNH3Cl, or by pyrolysis of RNH2BH3.
Borazine is thermally stable at 0 C, but decomposes slowly at ambient temperature. Borazine hydrolyzes slowly, but trihaloborazines hydrolyze quite rapidly. Hydrogen halides form 1 : 3 adducts with borazine, which decompose to trihaloborazines on warming.