Sikafloor® -24N PurCem (CN) Medium Duty Self-Levelling Polyurethane Screed
发布时间：2023/05/15
Product Data Sheet
Edition 20/03/2012EN
Sikafloor® -24N PurCem (CN)
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Sikafloor® -24N PurCem (CN)
Sikafloor® -24N PurCem (CN)
Medium Duty Self-Levelling Polyurethane Screed
Product
Description
Sikafloor® -24N PurCem (CN) is self-levelling, medium duty, coloured, four -
component, odourless, water dispersed polyurethane-based / cement and
aggregate screeds designed to provide good resistance to abrasion, impact,
chemical attack and other physical aggression. Sikafloor ® 24N Purcem (CN) has
an aesthetic, easy to clean, smooth aggregate texture. The system is typically
installed at 2 to 6 mm thickness.
Uses
Typically used in food processing plants, wet & dry process areas, freezers &
coolers, dairies, breweries, wineries, distilleries, laboratories, chemical process
plants, pulp and paper plants, warehouses and storage areas.
Characteristics /
Advantages
Resists a very wide range of organic and inorganic acids, alkalis, amines, salts
and solvents. Consult Sika Technical Sales for full details. Refer to the Sikafloor®
PurCem (CN) Chemical Resistance Chart.
Similar coefficient of thermal expansion to concrete allowing movement with the
substrate through normal thermal cycling. It will perform and retain its physical
characteristics through a wide temperature range from -20ºC up to 80ºC.
Bond strength in excess of the tensile strength of concrete, concrete will fail first.
High abrasion qualities result from its pure silica aggregate structure.
Extra Expansion joints are not necessary; simply maintain and extend existing
expansion joints up through the Sikafloor® PurCem (CN) Flooring System.
Easily maintained.
Test
Approval / Standards
ISEGA – Germany Food Stuff Contact Compliance. Certificate No: 32054 U 11
Product performances Test. Certificate No: GD2010-10-00222
Technical Data
Packaging
Component A: 5 kg/pail Component B: 5 kg/pail
Component C: 21.8 kg/bag, Component D: 1.6 kg/bag
Colour
Seven standard colours are available (all are approximate):
Beige, Maize Yellow, Oxide Red, Grass Green, Slate Grey, Dusty Grey, Traffic
Grey
Custom colors subject to minimum orders.
Yield
Approximately 2.0 kg/m2 /mm
Approximately 8.65 m2 per unit at 2 mm
Approximately 4.32 m2 per unit at 4 mm
(These figures do not allow for surface porosity, profile or wastage)
Shelf Life
Components A+B: 1 year in original unopened packaging.
Component C and D : 6 months in original unopened packaging.
Store dry between 18 ºC - 25 ºC. Protect from freezing.
Mix Ratio
Components A:B:C:D = Mix full units only.
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Sikafloor® -24N PurCem (CN)
Properties at 23°C and
50% R.H.
Application Temperature
10ºC min. / 30ºC max.
Optimal application temperatures range : 15ºC - 25ºC
Density ASTM C 905
1.93 kg/L
Flow ASTM C230
330 mm
Service Temperature
Typical service temperature range: -5ºC min. / 70ºC max.
The product will retain its physical characteristics up to -20ºC service temperature
however at such low temperature the Sikafloor 24N Purcem (CN) system thickness
must be increased (typically to 2 mm scratch coat + 4 mm body coat) in order to
withstand heavy wear and/or impact.
Temporary exposure to +80ºC is also possible when system building is at least 4
mm thick.
For exposure to higher temperature, please consult us.
The product is not designed to withstand thermal shock.
Hot steam cleaning is not recommended.
Cure Time at
Working Time 20-25 min at 20ºC
Initial join up time 25-30 min at 20ºC / 4 mm
Cure to foot traffic 10-12 h at 20ºC / 4 mm
Cure to light traffic 14-16 h at 20ºC / 4 mm
Full cure 5 days at 20ºC / 4 mm
Note: At low temperature the curing need longer time.
Softening Point
130 ºC
Compressive Strength
ASTM C579
24 h 27 MPa
7 days 37 MPa
28 days 40 MPa
Tensile Strength ASTM C
307
6.5 MPa
Flexural Strength ASTM
C 580
14.7 MPa
Bond Strength ASTM D
4541
> 1.75 MPa (substrate failure)
Hardness, Shore D ASTM
D 2240
80-85
Impact Resistance ASTM
D 2794
6.81 joules at 3 mm of thickness
Abrasion Resistance
ASTM D 4060
H-22/1000 cycles/1000 g
-2.26 g
Coefficient of Friction
ASTM D 1894-61T
Steel 0.3
Rubber 0.5
Coefficient of Thermal
Expansion ASTM D 696
1.6 x 10-5 mm/mm/ºC
Water Absorption ASTM
C 413
0.10%
VOC (GB/T 22374-2008)
< 30 g/L
Chemical Resistance
Consult Sika Technical Sales
How to Use
Surface Quality and
Preparation
The concrete substrate must be sound and of sufficient compressive strength
(minimum 25 N/mm2 ) with a minimum pull off strength of 1.5 N/mm2 .
The substrate must be clean and dry (when using primer of Sikafloor -156/-161, the
moisture content should be < 4%) and free of all contaminants such as oil, grease,
coatings and surface treatments, etc.
Remove all dust, dirt, existing paint films, efflorescence, exudates, laitance, form 3
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oils, hydraulic or fuel oils, brake fluid, grease, fungus, mildew, biological residues or
any other contaminants which may prohibit good bond. Prepare the surface by
appropriate mechanical means, approved by Sika to achieve (CSP 3-9). Repairs to
cementitious substrates, filling of blowholes, leveling of irregularities, etc. should be
carried out using an appropriate Sika profiling mortar.
Contact Sika Technical Sales for a recommendation.
Edge Terminations - All free edges of a Sikafloor® PurCem (CN), whether at the
perimeter, along gutters or at drains require extra anchorage to distribute
mechanical and thermal stresses. This is best achieved by forming or cutting
grooves in the concrete. Grooves should have a depth and width of 2 times
thickness of the Sikafloor® PurCem (CN) mortar. Refer to the edge details provided.
If necessary, protect all free edges with mechanically attached metal strips.
Never featheredge, always turn into an anchor groove.
Expansion Joints - Should be provided in the substrates at the intersection of
dissimilar materials. Isolate areas subject to thermal stresses, vibration movements
or around load-bearing columns and at vessel sealing rings. Refer to details.
Mixing
Mixing will be affected by temperature; condition materials for use from 15ºC to
25ºC. Premix components A and B separately, make sure all pigment is uniformly
distributed.
Start mixer; stir for 20 seconds component A, then add component B and mix for 30
seconds. Add component C (powder) and component D (pigment powder)
together, pouring slowly over a period of 15 seconds. DON’T DUMP!
Allow component C and D to further mix for 2 more minutes to ensure complete
mixing. During the operations, scrape down the sides and bottom of the container
with a flat or straight edge trowel at least once (Components A+B+C+D) to ensure
complete mixing. Mix full units only.
Note: Improve flowability on cool substrates can be achieved by removing a
maximum of 1 kg of Component C (powder) per unit.
Application Sikafloor® -24N PurCem (CN)
Priming – Use of Sikafloor® -156/-161 primer or a scratch coat of Sikafloor® -24N
PurCem (CN) is mandatory. (please consult Sikafloor® -156/-161 product data
sheet for details on mixing and application).
Sikafloor® -156/-161 primer is applied at rate of 0.3 to 0.5 kg/m². (Depending on
substrate conditions). Sikafloor 156 primer shall be lightly broadcast with quartz
sand 0.4-0.7 mm.
Before applying Sikafloor® 24N Purcem (CN) on Sikafloor® -156/-161 slightly
broadcast, allow:
Waiting time
Substrate temperature Minimum Maximum
+10°C 24 hours 12 days
+20°C 12 hours 7 days
+30°C 6 hours 4 days
Alternatively, if a scratch coat of Sikafloor® 24N Purcem (CN) is applied (at typical
rate of 2 kg/m²), it shall be let cured overnight (~14 hours at 20ºC) prior the body
coat application. (Note: Using Scratch coat of Sikafloor 24N Purcem (CN) is
particularly suitable when designed total build-up is 6 mm thick)
Sikafloor 24N Purcem (CN) - Mix and pour the Sikafloor®-24N PurCem (CN)
materials on the floor. Spread to the desired thickness using a notched squeegee,
trowel or screed bar. Take care to spread newly mixed materials across the
transition of previous applied mixes before the surface begins to set. Immediately
spike roll the surface to release trapped air in the matrix.
Respect curing times, prior to open Sikafloor 24N Purcem (CN) to traffic.
Clean Up
Clean all tools and equipment with Sika® Equipment Cleaner/Epoxy Thinner. Wash
soiled hands and skin thoroughly in hot soapy water or use Sika® Hand Cleaner.
Once hardened, product can only be removed mechanically.
Maintenance
Sikafloor® PurCem (CN) floors are easily cleaned using a stiff brushing action and
or high-pressure water, preferably hot, and even live steam. Degreasing agents and
detergents will assist, but do not use any compounds containing Phenol as the floor
colour may be damaged. Consult the cleaning compound manufacturer’s printing
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Limitations
Do not apply below 10ºC or above 30ºC / maximum relative humidity 85%.
Do not apply to un-reinforced sand cement screeds, asphaltic or bitumen
substrate, glazed tile or non-porous brick, tile and magnesite, copper,
aluminium, soft wood, or urethane composition, elastomeric membranes, fibre
reinforced polyester (FRP) composites.
Do not apply to wet or green concrete or polymer modified patches if the
moisture content >10%.
Do not apply to concrete if air or substrate temperature is within 3ºC of dew
point.
Protect substrate during application from condensation from pipes or any
overhead leaks.
Do not apply to vertical or overhead surfaces / for vertical surfaces refer to
Sikafloor® 29N PurCem (CN).
Do not featheredge.
Do not mix Sikafloor® PurCem materials by hand / mechanical mix only.
Do not apply to cracked or unsound substrates.
Do not apply to surfaces where moisture vapour can condense and freeze.
Steam cleaning may lead to delamination due to thermal shock (Use Sikafloor® -
19N PurCem (CN) or Sikafloor® -20N PurCem (CN) ).
Colour uniformity cannot be completely guaranteed from batch to batch
(numbered). Take care when using Sikafloor® PurCem products to draw from
inventory in batch number sequence, do not mix batch numbers in a single floor
area.
Always allow a minimum of 48 hours after product application prior to placing
into service in proximity with food stuffs.
Products of the Sikafloor® - PurCem® (CN) product range are subject to
yellowing when exposed to UV radiation. There are no measurable losses of
other properties when this occurs and it is a purely aesthetical matter. Products
can be used outside provided the change in appearance is acceptable by the
customer.
Caution Component A - Frequent or prolonged skin contact may cause some local short
term skin irritation. Avoid eyes contact, may cause slight transient irritation.
Component B - Harmful by inhalation. Irritating to eyes, respiratory system and
skin. May cause sensitization by inhalation and skin contact.
Component C and D- Risk of serious damage to eyes. In case of contact with
eyes, rinse immediately with plenty of water. May cause skin irritation. Avoid
breathing dusts. Respirable dusts could if inhaled over a prolonged period
constitute a health hazard.
Consult product label for additional information.
First Aid
In case of skin contact, wash thoroughly with soap and water. For eye contact, flush
immediately with plenty of water for at least 15 minutes. Contact a physician
immediately. For respiratory problems, transport victim to fresh air.
For more information, consult Sika Material Safety Data Sheet.
Value Base
All technical data stated in this Product Data Sheet are based on laboratory tests.
Actual measured data may vary due to circumstances beyond our control.
Local Restrictions Please note that as a result of specific local regulations the performance of this
product may vary from country to country. Please consult the local Product Data
Sheet for the exact description of the application fields.
Health and Safety
Information
For information and advice on the safe handling, storage and disposal of chemical
products, users shall refer to the most recent Material Safety Data Sheet containing
physical, ecological, toxicological and other safety-related data.
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Notes:
The information, and, in particular, the recommendations relating to the application and end-use of Sika products, are given in
good faith based on Sika's current knowledge and experience of the products when properly stored, handled and applied
under normal conditions in accordance with Sika’s recommendations. In practice, the differences in materials, substrates and
actual site conditions are such that no warranty in respect of merchantability or of fitness for a particular purpose, nor any
liability arising out of any legal relationship whatsoever, can be inferred either from this information, or from any written
recommendations, or from any other advice offered. The user of the product must test the product’s suitability for the intended
application and purpose. Sika reserves the right to change the properties of its products. The proprietary rights of third parties
must be observed. All orders are accepted subject to our current terms of sale and delivery. Users must always refer to the
most recent issue of the local Product Data Sheet for the product concerned, copies of which will be supplied on request.
Sika (China) Ltd.
No.28 Jingdong Road, Suzhou Industrial Park,
JiangSu,P.R.China
Postal Code: 215121
ISO 9001: 2008 ISO 14001:2004
Certificate No.:CC3576 Certificate No.:CC3577
The product is manufactured under a HKQAA
ISO9001/ISO14001
certified quality/environmental management system.
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