Styrene

  • Ethenylbenzene
  • Phenylethylene
  • Vinylbenzene
  • Cinnamene
  • Styrene monomer
Formula C6H5CH=CH2
Structure
Description Colorless to light yellow liquid with a sweet, almost floral odor at low concentrations, sharp, penetrating, odor at high concentrations.
Uses Manufacture of plastics, synthetic rubber, insulator.

Registry Numbers and Inventories.
CAS 100-42-5
EC (EINECS/ELINCS) 202-851-5
EC Index Number 601-026-00-0
EC Class Flammable; Harmful; Irritant
EC Risk Phrase R 10 20 36/38
EC Safety Phrase S 23
RTECS WL3675000
RTECS class Tumorigen; Mutagen; Reproductive Effector; Human Data; Primary Irritant
UN (DOT) 2055
Merck 12,9028
Beilstein/Gmelin 1071236
Beilstein Reference 4-05-00-01334
Swiss Giftliste 1 G-2896
Canada DSL/NDSL DSL
US TSCA Listed
Austrailia AICS Listed
New Zealand Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Odor Threshold Odor threshold 0.047 ppm
Properties.
Formula C8H8
Formula mass 104.15
Melting point, °C -31
Boiling point, °C 145.2
Vapor pressure, mmHg 5 (23 C)
Vapor density (air=1) 3.6
Saturation Concentration 0.59% at 20 C
Critical temperature 373
Critical pressure 39.5
Density 0.906 g/cm3 (20 C)
Solubility in water Insoluble
Viscosity 0.751 cp (20 C)
Surface tension 32.14 g/s2 at 19 C
Refractive index 1.5463 (20 C)
Dipole moment 0.027 D
Dielectric constant 2.46 (20 C)
Partition coefficient, pKow 2.95
Heat of fusion 10.96 kJ/mol
Heat of vaporization 43.96 kJ/mol
Heat of combustion -4381 kJ/mol

Hazards and Protection.
Storage Keep away from sources of ignition. Store in a cool place in the original container and protect from sunlight. Refrigerator/flammables.
WHMIS B2 D2A D2B F
Handling Wash thoroughly after handling. Use only in a well ventilated area. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Take precautionary measures against static discharges. Wash clothing before reuse. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.
Respirators A half-face organic vapor respirator may be worn for up to ten times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. A full-face piece organic vapor respirator may be worn up to 50 times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. For emergencies or instances where the exposure levels are not known, use a full-face piece positive-pressure, air-supplied respirator.
Small spills/leaks Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation.
Disposal code 1
Stability Stable under normal temperatures and pressures.
Incompatibilities Vapor is explosive when exposed to heat or flame; reacts with oxygen above 40C (104F) to form a heat-sensitive explosive peroxide. On exposure to light and air, styrene slowly undergoes polymerization and oxidation with formation of peroxides. Violent polymerization may be initiated by alkali metal-graphite composites, butyllithium, dibenzoyl peroxide, azoisobutyronitrile or di-tert-butyl peroxide. Styrene reacts violently with chlorosulfonic acid, oleum, sulfuric acid, chlorine + iron(II)chloride and can react vigorously with oxidizing materials. Dissolves rubber. Corrosive to copper and copper alloys. Incompatible with peroxides, aluminum chloride, strong acids, metallic salts, halogens, polymerization catalysts and accelerators.
Decomposition Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C 31
Autoignition, °C 480
Upper exp. limit, % 6.8
Lower exp. limit, % 0.9
Fire fighting Wear full protective clothing and NIOSH-approved self-contained breathing apparatus with full facepiece operated in the pressure demand or other positive pressure mode. Extinguishing media: Water spray, dry chemical, alcohol foam, or carbon dioxide. Material floats on water and may travel back to an ignition source and spread fire. Water spray may be used to keep fire exposed containers cool. Do not allow water runoff to enter sewers or waterways.
Fire potential Flammable liquid and vapor.
Hazards Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back. At elevated temperatures such as in fire conditions, polymerization may take place which may lead to container explosion.
Combustion products Toxic gases and vapors (such as carbon monoxide) may be released in a fire involving styrene. Styrene fumes are very acrid.
NFPA Health 2
  Flammability 3  
  Reactivity 2  

Health.
Exposure limit(s) OSHA PEL: TWA 100 ppm C 200 ppm 600 ppm (5-minute maximum peak in any 3 hours) NIOSH REL: TWA 50 ppm (215 mg/m3) ST 100 ppm (425 mg/m3) NIOSH IDLH: 700 ppm
Carcinogin I-2B
Poison_Class 3
Exposure effects Repeated exposure may cause nausea, vomiting, appetite loss, a sensation of drunkenness, general weakness, and functional disorders of the nervous system and liver. May cause dermatitis. Women may experience ovulation and menstrual disorders. May cause mutagenic and teratogenic effects.
   Ingestion May cause irritation to the gastrointestinal tract. Symptoms may include nausea, vomiting and diarrhea. May cause central nervous system depression. Symptoms may include lethargy, drowsiness, staggering and sleepiness. May cause possible convulsions and risk of pulmonary edema.
   Inhalation Causes irritation to the respiratory tract. Symptoms may include coughing, shortness of breath. A central nervous system depressant. Higher exposures can cause a build-up of fluid in the lungs (pulmonary edema), a medical emergency.
   Skin Causes irritation to skin. Symptoms include redness, itching, and pain. May produce blisters. May be absorbed through the skin.
   Eyes May cause irritation, redness, pain, and corneal damage.

First aid
 
   Ingestion Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
   Skin Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists. Wash clothing before reuse.
   Eyes Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
UN number 2055
Response guide 128
Hazard class 3
Packing Group III  
USCG CHRIS Code STY  
USCG Compatatibility Group 30 Olefins
HS Code 2902 50 00  
Std. Transport # 4907265 4907235  
IMO Chemical Code #
IMO Pollution Category B
IMO Hazard code S/P