Nukote ST-pw

NUKOTE ST®-pw is a pure aromatic polyurea modified specifically to meet requirements for use in coating substrates utilised for storage and transmission of potable and drinking water. It is an ANSI/NSF 61 compliant and approved pure polyurea barrier material and also conforms to global migration Standard US – FDA: 21 CFR 175 – 300. Nukote ST-pw is tested and approved by many countries for applications on substrates in contact with potable water and food products. It is a plural component, fast set, 100% solids product suitable for concrete, steel, and other substrates as a waterproofing membrane, anti-corrosion and abrasion resistant liner. This aromatic Polyurea Elastomer also displays good chemical resistance, thermal stability and UV resistance. It can be applied by spray in single or multiple layers to form a tough but flexible homogenous membrane

FEATURES:

• ANSI/NSF 61 approved for potable water
• Meets global migration standard US – FDA: 21 CFR 175 – 300
• 100% solids with zero VOC
• Fast reactivity and cure time resulting in almost immediate return-to-service time
• Performs in constant process temperatures from -40 °F to 250 °F (-40 °C to 120 °C)
• Maintains high physical properties on weathering
• Superior elongation and tear properties
• Seamless, resilient, flexible and durable
• Excellent corrosion protection
• High impact and abrasion resistance
• Continuous thermal stability
• Resistant to many solvents, acids and alkalis (consult NCSI)
• Low permeability waterproofing membrane

TYPICAL USES:

• Potable water treatment plants and potable water pipelines
• Concrete / Steel water storage tanks
• Desalination and water treatment plants
• Catering facilities, food processing plants, food preparation areas
• Dairies and livestock farming facilities
• Cold storage facilities and refrigerated vehicles
• Pharmaceutical, sterile and clean – room areas
• Aquariums, ponds, aqueducts and reservoirs

COLORS:

Standard medium grey only. Custom colors, blended to match any RAL number, are available upon request subject to minimum quantity.

PACKAGING:

100-gallon (380-liter) drum sets, shipped in metal drums of 50 gallons (190 liters) each of side A and side B

10-gallon (38-liter) kits, shipped in plastic pails of 5 gallons (19 liters) each of side A and side B

275-gallon (1045 liter) totes.

COVERAGE:

Nukote ST-pw may be applied at any rate to achieve the desired thickness. Calculation for theoretical coverage: 40 Ft² /gal @ 40 mils (1 m²/liter @ 1mm).

TECHNICAL DATA (All values @ 77 ºF / 25 ºC)	US	Metric
Solids by volume (ASTM D2697)	100%	100%
Volatile organic compounds (ASTM D2369)	0 lb./gal	0 gm/ lit
Theoretical coverage	40 ft²/gal @ 40 mils	1m²/ lit @ 1mm
Specific Gravity of materials (ASTM D792)	A: 9.39, B: 8.43 lbs./gal	A: 1.13, B: 1.01 kg/ liter
Viscosity at 158 ºF/70 ºC in cps ±10% (ASTM D4878)	A-260, B-380	A-260, B-380
Shelf life @ 77 ºF /25 ºC	12 to 18 Months	12 to 18 Months
Tensile strength (ASTM D412-C)	3000 to 3800 psi	21 to 27 MPa
Elongation (ASTM D412-C)	400-475 %	400-475 %
Hardness (ASTM D2240)	45 to 55 Shore D	45 to 55 Shore D
Flexibility (2mm mandrel ASTM D522)	Pass	Pass
Water vapour transmission rate (ASTM E96)	0.037-0.038grains/hr-ft²	0.2 to 0.3gms/hr-m²
Water absorption -24 hours (ASTM D570)	~ 1 %	~1%
Crack Bridging @ -13 ºF/-25 ºC (ASTM C1305), 25 cycles	Pass	Pass
Tear strength (ASTM D642 )	450 to 500 pli	75 to 85 Kn/m
Impact Resistance (ASTM G14), No Holidays	> 200 in-lbf	> 20 J (N-m)
Fire Rating (ASTM E108)	Meets Class A for Flame spread
Flash point Pensky Martin	>200 ºF	>93 ºC
Service temperature (Dry)	-40 ºF to 250 ºF	-40 ºC to 120 ºC
Abrasion Resistance (ASTM D4060) weight loss	< 8 mg loss Taber CS 17 wheel 1Kg/1000 rev

PROCESSING PROPERTIES (Under standard lab conditions)
Mix Ratio V/V	1:1
Gel time	6 to 20 seconds
Tack free time (DFT & Temperature dependent)	30 to 45 Seconds
Post cure time	24 hours
Properties and values are highly dependent on equipment, spray gun, mix chamber temperature, pressure and related parameters. Variations are possible and expected.

STORAGE:

Twelve to eighteen months in factory delivered, unopened drums. Store on pallets and keep away from extreme heat, freezing, and moisture. The use of drum heaters is encouraged to reduce material viscosity at low temperatures

MIXING:

Nukote ST-pw might not be diluted under any circumstance. Thoroughly mix Nukote ST-pw Part B resin material with air driven power equipment until a homogeneous mixture and color is obtained. Always use dedicated spray equipment.

SURFACE PREPARATION:

Concrete:

The surface of a concrete subfloor should be dry, smooth, structurally sound and free of depression, scale, or foreign deposits of any kind. Remove all curing compounds. Abrasive blast, sweep blast or water blast to remove all latent material and expose voids. Use a good quality epoxy filler or mortar for void and spall filling, skim coat or repairs. Prime, fill imperfections in the substrate surface to limit out-gassing. All concrete substrates, on or below grade level should be tested for moisture content. On-grade or below-grade concrete floors or slabs should have a moisture barrier installed to protect from ground moisture. The surface preparation of concrete should meet and conform to Joint NACE 6/SSPC-SP 13 standards and achieve a concrete surface profile of CSP 3 to CSP 6 as per ICRI Guideline No.03732 for optimum performance.

Metal:

All surfaces should be clean and free from contamination. The surface should be assessed and treated in accordance with ISO 8504, Abrasive blast the surface to minimum NACE-2/SSPC SP-10/Sa 2.5, as per ISO 8501-1, for a visual assessment of surface cleanliness with an anchor profile of 3 to 4 mils (75 -100 microns). Soluble salts must be removed to an acceptable levels. Refer to NCSI surface preparation manual for detailed procedures for different types of substrates.

APPLICATION:

Must be applied utilizing high-pressure, heated plural component spray proportioning equipment, such as Graco Reactor 2, or equivalent, capable of delivering materials without loss of pressure or drop in temperature for the appropriate hose length on a consistent basis. For optimum performance, the substrate should be abrasive blasted. Concrete substrates should be allowed to cure a minimum of 30 days. On concrete, Nukote ST-pw should always be applied over a suitable primer for maximum adhesion. For all submersed or immersion applications, use of a suitable primer is absolutely essential. On horizontal surface applications, a texture “stipple” coat can be applied for non-skid purposes, after reaching the initial desired film thickness. Recommended DFTs are a function of the project specific requirements. Please review your specific project with Nukote technicians.

EQUIPMENT CLEAN UP:

Cured product may be disposed of without restriction. Uncured Isocyanate and resin portions should be mixed together and disposed of in accordance with local regulations. Containers should be disposed of according to local environmental laws and ordinances.

LIMITATIONS:

Do not open until ready to use, and store in a sealed container after opening. Adding a nitrogen blanket is strongly recommended for the ‘A’ component when storing after opening.

WARNING:

This product contains Isocyanate and curatives

CHEMICAL RESISTANCE:

Each Nukote product formulation has varying levels of resistance to specific chemicals. Please review the chemical immersion test data included in the Nukote Test Book for general resistance to specific chemicals at specific concentration levels. Chemical concentrations are complex and when combined with temperatures above ambient levels this complexity increases exponentially. Contact Nukote Technical Personnel for specific recommendations for chemical resistance prior to specifying these products in this application type. Consult with NCSI for more details on product and chemical resistance. The following chart is the results of Polyurea immersed in chemicals and tested as per modified ASTM D 3912.

Chemicals	Resistance
Hydrochloric acid upto 10%	R
Sulphuric Acid 15%	R
Phosporic Acid 10%	R
Acetic Acid 10%	R
Sea water	R
Waste Water	R
Water @ 176 ºF (80 ºC)	R
Hydrogen Sulphide (gas)	R
Sodium Hydroxide-50%	RC
Ammonium Hydroxide 20%	R
Ammonium Hydroxide 50%	RC
Pottasium Hydroxide 10%	R
Pottasium Hydroxide 20%	RC
Sodium Hydroxide 20%	R
De ionized Water	R
Diesel Fuel, Gasoline (unleaded)	R
Motor Oil, Brake Oil	RC
Hydraulic Oil	R

R = Resistant, RC = Slight surface change or discolouration with no loss of hardness

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