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Polyester Resins General Safety Data

The advice given in this safety data sheet covers all grades of polyester resins which are solutions in styrene monomer. Most of these grades have the warning "Flash point in the range of 22°C - 32°C" on the container. A very few (currently two) special grades also contain some methyl methacrylate monomer. These grades have the warning "Highly Flammable" on the container. The advice covers both types of resin.
There are also a few (currently two) grades which do not contain any monomer. These are of high flash point (low fire hazard) and are referred to in a separate data sheet "SOLVENT FREE RESINS". These resins have no fire hazard warning on the container.

Section 1. Supplier's Details
Product:
Polyester resins which are solutions in
styrene with or without other monomers.

Suppliers:
K & C Mouldings (England) Limited,Spa House, Shelfanger,Diss Norfolk IP22 2DF. Telephone No: Diss (01379) 642660

Product Description:
Solution of unsaturated polyester resin in styrene with or without other monomers.

Section 2. Nature of Hazards and Precautions

A. Fire Hazard
Polyester resins are flammable and have a flash point (Abel closed cup of approximately 32°C) (90°F) if containing only styrene monomer. Resins containing some methyl methacrylate monomer have lower flash points dependent upon the methyl methacrylate content. The requirements of the Highly Flammable and Liquified Petroleum Gases Regulations Act 1972 apply. In particular:

i) Polyester resins must not be exposed to heat or sources of ignition.

ii) Smoking must be prohibited in areas where polyester resins are handled.

iii) Spillages must be cleaned up promptly and any resin contaminated material used for cleaning disposed of in an approved manner. (See Section 6).

iv) Adequate ventilation, particularly of curing ovens must be provided.

The advice of the Factory Inspectorate and Fire Officer should be obtained.

B. Toxic Hazards

i) SWALLOWING
Polyester resins do not have high oral toxicity. Every effort should be made to avoid accidental ingestion, as with all chemical products.

ii) SKIN CONTACT
Polyester resins can cause dermatitis. This is probably due to the styrene dissolving the skin's natural protective grease. Susceptibility varies between individuals. Working processes should not normally allow the resin to come into contact with operators' hands, and then the careful use of barrier cream before commencing work and skin cleansing cream after work provides adequate protection. If operators' hands are likely to come in contact with resin then gloves should be worn in addition to using the creams. In addition to particular protection to the hands, general protection with aprons or overalls should be provided and used. If there is any possibility of resin entering the eyes, goggles should be worn. The resin is irritating to the eyes and contact will be painful.

iii) INHALATION
Polyester resins give off styrene monomer. This monomer is toxic and inhaling it can cause giddiness and sickness at low concentrations, and at high concentrations can be fatal. The maximum allowable concentration is 100 ppm. Equipment to measure the styrene content of air, normally by the colour change of a detector tube, is available.
The styrene concentration in the air must be controlled by adequate ventilation. Ventilation is particularly important in curing ovens, where high concentrations of styrene vapour can accumulate. Ovens exceeding 1.5m3 (approx. 50 cu. ft.) must have mechanical ventilation with external motors and fire resisting ducts.

Section 3. Emergency Action

This can be a misleading description. Think of a small fire as a large fire in its early stages. Quick effective action is required, and for this dry powder or foam extinguishers are required, which must be provided in adequate numbers in suitable locations with trained personnel. The Fire Officer will be glad to give excellent advice. Always call the Fire Brigade. Water or soda-acid extinguishers tend to spread small areas of burning resin and are not recommended.

ii) LARGE FIRES
If a large fire should develop it must usually be dealt with by the Fire Brigade, and the Factory concentrate on orderly evacuation, so avoiding any danger to life. Consider the installation of an automatic sprinkler system, which will often save its cost in reduced fire insurance premiums.

iii) SMALL SPILLAGE
This should be cleaned up promptly with rag or absorbent paper. The contaminated material must be disposed of in a proper manner. (See Section 7).

iv) LARGE SPILLAGE
All areas where spillage may occur must be contained so that the spilt resin can be drained off. Any other spillage should be absorbed in suitable material, i.e. dry sand, or sawdust, and shovelled and swept up. Waste disposal precautions are important. (See Section 6).

v) SMALL SKIN CONTACT
This is not normally a hazard if barrier cream has been used. Wash off and re-apply cream.

vi) LARGE SKIN CONTACT
Do not use solvent such as acetone or xylene to remove resin from the skin. Apart from the fire risk the risk of skin irritation and possible dermatitis will be increased. Remove the resin with skin cleansing cream and wash with soap and water.

vii) INGESTION
Do not induce vomiting but seek medical attention without delay.

viii) INHALATION
If giddiness or sickness or any ill effect should be caused by inhalation of styrene vapour the affected person should be taken to fresh air, kept warm, and rested while medical attention is obtained. If breathing should stop then artificial respiration must be administered.

ix) EYE CONTACT
Flush promptly with plenty of water and seek medical attention immediately.

Section 4. Health Hazard Data

The effect of various concentration of styrene has been reported as follows:

Section 5. Handling and Storage

The storage of polyester resins is subject to the requirements of the Highly Flammable Liquids and Liquified Petroleum Gases Regulations, which include:

i) Polyester resin storage must either be in the open air and covered with polythene and preferably away from direct sunlight, or in a store which is a fire resisting structure, or in a store in a "safe position" (not defined but may mean isolated). Provision must be made for any spillage to be contained. Stores or storage areas must be boldly marked "Highly Inflammable".

ii) The quantity of polyester resin kept in working areas must not exceed 50 litres (approx. 60 kilos) and must be kept in closed vessels in a fire resisting leak proof cupboard or bin.

iii) Conveyance from stores to working areas should preferably be through a totally enclosed pipework system. Closed vessels designed to avoid spilling or leakage may be used where this is impractical.

Polyester resin will polymerise and gel if not stored correctly. Resin should preferably be stored at temperatures not higher than 20°C (68°F) when the shelf life of most grades will be six months minimum. Very low storage temperatures result in long shelf life but a large increase in resin viscosity, and for many applications cold resin must be brought to workshop temperatures before use. Water must be excluded from all storage containers as this causes slow curing, and will also cause rust to form in steel drums and tanks. Rust is also a cause of premature gelation.

Section 6. Waste Disposal

Any rag or absorbent paper or other material used  for cleaning up resin is a fire hazard, as heat and spontaneous combustion can occur, particularly if the resin was catalysed., Also quantities of catalysed resin above 0.1 kilo can generate hazardous exothermic heat if allowed to polymerise in a mass. All soiled or waste materials must be water soaked, and kept in a closed bin until disposed of. Dispose of all waste on a daily basis or more frequently.
Small quantities of resin and resin contaminated waste can be disposed of by burning in an approved incinerator, which will not emit smoke or sparks, and is located in a safe place. Larger quantities of waste are normally disposed of by a waste collection contractor.
This safety data sheet is in the format recommend by the British Resin Manufacturer's Association to whom due acknowledgement is made.

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