TrueKote CS-252 is a two component, high performance elastomer, for coating or casting TrueKote CS-252 to a high performance urethane elastomer that has high, excellent physical properties and outstanding resistance to abrasion. TrueKote CS-252 may also be used as a coating for soft foam, floor coatings, flexible bumper, and impact resistance pads for playgrounds, horse farms and polymer rope applications. TrueKote CS-252 may also be used as a protective coating for outstanding extended wear application on most metallic surfaces.

TrueCast CS 252 is a flexible rubber potting compound used to cast around the neck of braided rope eyes. This product is used with a mould to cast in place rubber onto rope and fabric. It provides flexibility and high elongation where rope eyes experience load stretching. TrueCast CS 252 is a US military specification product used in the manufacture of helicopter lifting slings. TrueCast CS 252 contains solvent and is classified as a flammable material for shipping purposes

Application and Mix Ratio


Standard techniques used in airless paint spraying work well with TrueKote CS-252. The proper spray tip should be selected for the job and the pressure of the pump should be adjusted to obtain an even spray pattern at the lowest pattern. The initial coat of TrueKote CS-252 should be a thin coat and should be applied from the bottom up so as to prevent overspray from depositing on the primed surface. On surfaces having a nap or rough texture, such as abraded rubber, optimum adhesive coats may be applied to a thickness of 5–20 wet mils, depending upon the position of the article being coated, the temperature and the elapsed time in the pot life. Each coat should be allowed to gel or dry to the touch, usually a period of 5–15 minutes, depending upon ambient temperatures, before the next coat is applied.


The resin portion of TrueKote CS-252 crystallizes when exposed to temperatures below 40˚F and the curative portion may crystallize when exposed to temperatures below 20˚F. This does not harm the components; however, the resin component should be warmed to 80˚F–100˚F and the curative component to room temperature and each component mixed well before using. The components should not be overheated and should be cooled to room temperature before mixing together. After long-term storage it is a good policy to stir each component before adding them together.

DO NOT mix resin and curative components until ready to use. The correct mixing ratio is 100 parts component A to 6.66 part component B by weight. TrueKote CS-252 will not cure properly if the correct component-mixing ratio is not used.

Mix the components together in a clean container using a power drill until a uniform blend is achieved. Scrape the sides and bottom of the container with a straight edge several times during the mixing operation to prevent unmixed material from sticking to the container. The total time required to mix the components should be about five minutes.

  1. Warm both components to room temperature before mixing.
  2. Remove lids with screw driver on one (1) gallon component A and one (1) quart component B can.
  3. Pour Color pack (½ pint can or metal tube) into component B (quart can).
  4. Pour all of component B (quart can) into component A (gallon can).
  5. Mix for three (3) minutes with drill and Jiffy mixer taking care not to mix in excess air.
  6. With a flat stick carefully scrape sides and bottom of container to ensure there are no unmixed components.
  7. Mix 1-½ additional minutes.
  8. Material will gel in 30 to 45 minutes depending on temperature hours. Material will be fully cured in 3 to 4 days (depending on temperature).
  9. Clean up equipment with Methyl Ethyl Ketone before material has fully cured.


Physical Properties (Liquid)

Mix Ratio (Weight)

100 parts A/ 6.68 parts B

Mix Ratio (Volume)

100 parts A/ 6.05 parts B


Resin Porperties

Curative Component

Mixed Component





Lbs. Per Gallon




Weight Solids, %




Volume Solids, %




Viscosity, Brookfield ccps, @ 75°F




Flash point, TCC








*Percent VOC can be formulated to 15% per individual customer needs.


Physical Properties (Cured)

Tensile Strength

ASTM D-412

4235 psi

Tear Strength

ASTM D-412

563 lbs./in.


ASTM D-412



75-80 Shore A


High or Low Temparature

TrueKote CS-252 has been successful at temperatures up to 180˚F. Under wet or humid conditions at elevated temperatures, TrueKote CS-252 is superior to most other urethanes. Although TrueKote CS-252 becomes stiffer at lower temperatures, it still remains flexible at temperatures as low as –70˚F.

Abrasion Resistance

TrueKote CS-252 has excellent abrasion resistance and will out wear many other materials when subjected to impingement or slurry abrasion.


Chemical Resistance

TrueKote CS-252 has excellent chemical resistance in the pH range of 2 to 12. Resistance to most oils at room temperature is good, but resistance to solvents is generally poor. The table below gives an indication of resistance to some chemicals; however, users should conduct their own tests.





Chlorinated Water


Sea Water


Nitric Acid, 5%




Hydrolchloric Acid, 5%


Methyl Ethyl Ketone


Phosphoric Acid, 10%









G – Good
E – Excellent
F – Fair
P - Poor


Cure Times

The time required for TrueKote CS-252 to cure is dependent upon temperature. A 75% cure is generally sufficient for mild abrasion and submersion. The cure times shown below are for a 100-mil thick coating; cure times should be increased by 50% for a 250-mil thick coating.





75% Cure

6 days

3 days

1 day

95% Cure

15 days

7 days

3 days

A 95% cure can be considered a complete cure for practical purposes, although all urethanes, including heat-cured urethanes, show improved physical properties after aging several weeks or months.


The theoretical dry coverage of TrueKote CS-252 is 1045-mil square foot per mixed gallon of material. Overspray and waste must be taken into account when estimating the quantity of material required for a particular project.


A single component airless spray machine with a minimum air: fluid pressure ratio of 20:1 will provide a good spray pattern with .015 to .026 inch orifice spray tip. When using larger spray tips or long hose lengths, it is advisable to use a machine with a 30:1 air: fluid pressure ratio. The spray machine should be equipped with Teflon packings, Teflon or nylon hose and a 100-mesh outlet filter. A tip filter may be required for small tips. The spray hose should be conductive and the spray machine should be grounded to an earth ground when spraying.

A Jiffy mixer or other propeller-type mixer used on air drill can be used to mix the urethane components.

Repair of Cured Coating

TrueKote CS-252 may be repaired by rough to a "suede" finish using a wire brush on and electric drill then clean the surface with M.E.K. (methyl ethyl ketone) then the application of more TrueKote CS-252.

Pot Life

The pot life of TrueKote CS-252 is approximately 30 minutes at 75˚F, 20 minutes at 100˚F and 45 minutes at 50˚F. After these times are exceeded for some additional time the material can still be sprayed using increased pressure or may be brushed or rolled on the substrate.


Vapors from TrueKote CS-252 contain isocyanates and solvents. Forced air ventilation must be used for all indoor applications. When working in tanks and other closed vessels or downstream from spray gun, fresh air breathing equipment should be worn. Chemical cartridge masks suitable for organic vapors may be used under some conditions with adequate ventilation. Protective clothing should be worn at all times. Both resin and curative components contain flammable solvents and should be protected from sparks and open flames.

Avoid contact of components with skin and clothing as both resin and curative can cause skin and eye burns. In case of eye contact, immediately flush eyes with plenty of water for at least 15 minutes. If swallowed, DO NOT induce vomiting. Call a physician at once. Keep out of reach of children.

Clean Up

Equipment must be cleaned immediately after use to prevent buildup of cured urethane on internal parts of equipment. Solvents such as toluene or MEK works well for cleaning soiled spray equipment. As soon as urethane spraying is completed, solvent should be pumped through the pump, hose and spray gun until solvent comes out clear. The spray gun should then be removed from the hose and the end of the hose put in the solvent container near the pump suction and solvent should be circulated through the system for 15–20 minutes. The spray gun should then be attached to the hose and the system purged with fresh solvent.

Dispose of all empty TrueKote CS-252 component containers in accordance with local, state and federal regulations. Empty component containers can be rendered non-hazardous by. Rinsing the containers with a small amount of mixed material and allowing the solvents to evaporate. The containers will then contain non-hazardous cured urethane

Storage and Shelf Life

TrueKote CS-252 components are shipped from the factory in sealed containers that are purged with dry nitrogen. The containers should be kept tightly sealed and stored in a cool and dry area that is protected from direct sunlight and moisture. Storage temperature should not exceed 80˚F. The shelf life of factory seal containers stored under these conditions is one year.

Containers that have been opened should be resealed immediately after material has been removed in order to prevent moisture contamination and solvent evaporation. Resin component containers should be purged with dry nitrogen if the contents are not used within 24 hours after opening


Shipping Class: Class 92.5 Hazardous