Chloroprene

  • Chlorobutadiene
  • 2-Chloro-1,3-butadiene
  • 2-Chlorobuta-1,3-diene
Formula
C4H5Cl
Structure
Description
A clear colorless liquid.
Uses
Used as a chemical intermediate in the manufacture of artificial rubber.

Registry Numbers and Inventories.
CAS
126-99-8
EC (EINECS/ELINCS)
204-818-0
EC Index Number
602-036-00-8
EC Class
Highly flammable; Harmful; Irritant
RTECS
EI9625000
RTECS class
Tumorigen; Mutagen; Reproductive Effector; Primary Irritant
UN (DOT)
1991
Beilstein/Gmelin
741875
Beilstein Reference
4-01-00984
Swiss Giftliste 1
G-1416
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C4H5Cl
Formula mass
88.54
Melting point, °C
-130.0
Boiling point, °C
59.4
Vapor pressure, mmHg
215
Vapor density (air=1)
4.2
Odor Threshold Odor threshold 0.40 mg/m3 (recognition).
Critical temperature
261.7
Density
1.038 g/cm3 (20 C)
Solubility in water
260 mg/L
Viscosity
0.394 cp (25 C)
Refractive index
1.4583 (20 C)
Partition coefficient, pKow
2.01
Heat of vaporization
29.5 kJ/mol

Hazards and Protection.
Storage
Oxidation.Inhibited by storage at less than -15C andor by the addition of antioxidants to the fresh distillate. Storage location should be close to laboratory where it is to be used, so that only small amounts need to be transported. Carcinogens should be kept in only one section of storage area, explosion-proof refrigerator or freezer as required. The area should be appropriately labeled. An inventory should be kept showing the quantity of carcinogen and date it was acquired. Facilities for dispensing should be contiguous to storage area.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate clothing to prevent any reasonable probability of skin contact. Wear eye protection to prevent any possibility of eye contact.
Respirators
Any self contained breathing apparatus with a full facepiece and operated in a pressure demand or other positive pressure mode or any supplied air respirator with a full facepiece and operated in a pressure demand or other positive pressure mode in combination with an auxiliary self contained breathing apparatus operated in pressure demand or other positive pressure mode.
Small spills/leaks
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors. Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commercial sorbents. Water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses.
Stability
Polymerizes on standing.
Incompatibilities
Sensitive to exposure to air and light Sensitive to heat Mixtures with water, DMSO, 95% ethanol or acetone should be stable for 24 hours under normal lab conditions Incompatible with peroxides and other oxidizing agents Attacks some forms of plastics, rubbers and coatings Incompatible with strong oxidizing agents Attacks some forms of plastics, rubbers and coatings.
Decomposition
When heated to decomposition it emits toxic fumes of chlorine (cl-).

Fire.
Flash Point,°C
-20
Upper exp. limit, %
20
Lower exp. limit, %
4
Fire fighting
Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use foam, dry chemical, or carbon dioxide.
Fire potential
Component 1 is flammable.
Hazards
Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion and poison hazard indoors, outdoors or in sewers.
Combustion products
Decomposes yielding toxic fumes Dangerous when exposed to heat or flame
Health
2
 
Flammability
3
 
 
Reactivity
1
 

Health.
Exposure limit(s)
OSHA PEL: TWA 25 ppm (90 mg/m3) skin NIOSH REL: Ca C 1 ppm (3.6 mg/m3) 15-minute See Appendix A NIOSH IDLH: Potential occupational carcinogen 300 ppm
Carcinogin
I-2B, N-2, CP65
Poison_Class
4
Exposure effects
Irritability, giddiness, and CNS depression may be seen. Chromosomal abnormalities and testicular damage have been reported. <br>Hydrocephalus and brain herniation have been seen in rat fetuses. <br>Physical and mental defects have been reported in children whose mothers worked in the polymerization area of a chloroprene rubber factory.
   Ingestion
Nausea and anorexia may be seen.
   Inhalation
Pneumonitis, leading to pulmonary edema, may be seen with inhalation of high concentrations.
   Skin
Dermatitis may be seen after skin exposure. Alopecia has been reported in humans exposed to chloroprene.
   Eyes
Inflammation of the eye, and focal necrosis of the cornea have been reported. Chloroprene is a lacrimator.

First aid
 
   Ingestion
DO NOT INDUCE VOMITING. Volatile chemicals have a high risk of being aspirated into the victim's lungs during vomiting which increases the medical problems. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. IMMEDIATELY transport the victim to a hospital.
   Inhalation
IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used.
   Skin
IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.
   Eyes
First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Transport.
UN number
1991
Response guide
Hazard class
3 (Forbidden for unstabilized)
Packing Group
I
 
USCG CHRIS Code
CRP
 
Std. Transport #
4907223