Sika ViscoCrete-2004 NS
A modified-polycarboxylate high-range water reducer that gives flowing, self-compacting concrete strong water reduction and dependable slump retention on Indian sites.
What is it?
A high-range water-reducing superplasticiser based on an aqueous solution of modified polycarboxylate (PCE), supplied as a brown liquid.
Where is it used?
High-strength and high-performance structural concrete, ready-mix, self-compacting concrete, precast and prestressed elements, and pumped pours.
Why use it?
It cuts mixing water sharply while holding workability longer, producing dense, durable, low-shrinkage concrete that flows and compacts with little vibration.
How is it applied?
Dosed at 0.2-2.0% by weight of cement, added after 50-70% of the mix water, then wet-mixed for at least 60 seconds.
About Sika ViscoCrete-2004 NS
Sika ViscoCrete-2004 NS is Sika’s polycarboxylate-ether (PCE) superplasticiser built for the demands of modern structural concrete, where engineers want both a big water reduction and a mix that stays workable long enough to place and finish. Supplied as a brown liquid at roughly 1.12 kg/l, it is dosed straight into the batch and works across ready-mix, precast, prestressed and site-batched concrete. For teams in Delhi NCR and across India, its appeal is practical: the same admixture that lets you pump a raft slab in summer heat can also produce the flowing, self-levelling mixes needed for congested reinforcement and architectural precast.
What separates a modern PCE like ViscoCrete-2004 NS from older naphthalene- or lignosulphonate-based plasticisers is the balance it strikes. Contractors get very high early flow for easy placement, ready-mix producers get retained slump for the journey from plant to pour, and structural designers get the low water-cement ratio that drives compressive strength and long-term durability. Because dispersion is so efficient, the same target strength can often be reached with less cement, which trims cost and the mix’s carbon footprint. It complies with IS 9103 and ASTM C494, so it fits comfortably into Indian specifications and QA documentation.
The technical insight
The performance comes down to how the polymer physically holds cement grains apart. A polycarboxylate molecule has a charged backbone that latches onto the cement particle and long side chains that project outward into the mix water. Once adsorbed, those side chains create a steric (physical) barrier as well as a small electrostatic charge, so neighbouring grains cannot flocculate into clumps. Older sulphonated admixtures rely mainly on electrostatic repulsion, which fades as hydration proceeds; the steric bulk of a PCE resists that collapse, which is why slump holds for longer. Freeing the water that was previously trapped inside those cement clumps is what delivers the water reduction: you can either keep the water and gain flow, or remove it and gain strength. The lower water-cement ratio produces a denser, less permeable matrix with fewer capillary pores, which is the real mechanism behind the improved durability and reduced drying shrinkage, not just easier handling on the day of the pour.
Where it is used
- High-strength and high-performance structural concrete where a low water-cement ratio is specified
- Self-compacting concrete (SCC) for heavily reinforced or complex sections that cannot be vibrated well
- Ready-mixed concrete requiring retained workability over long haul and placement times
- Precast and prestressed elements needing high early strength and a clean, dense finish
- Pumped concrete for foundations, rafts, walls, columns and elevated slabs
- Water-reduced mixes targeting improved durability and reduced permeability
- Architectural and fair-faced concrete where flow and surface finish matter
- Hot-weather pours where extended workability retention prevents premature stiffening
Key advantages
- Very high water reduction for a given workability, lifting compressive strength at all ages
- Retained slump and workability, giving ready-mix and long-haul deliveries a wider placing window
- Excellent flow and self-compaction, reducing or removing the need for vibration
- Denser, less permeable concrete with better long-term durability and lower drying shrinkage
- Improved cohesion and reduced bleed and segregation in well-designed mixes
- Potential cement savings at a target strength, trimming cost and embodied carbon
- Compatible with a wide range of Indian cements and suited to IS 9103 / ASTM C494 specs
- Single-component liquid that dispenses easily through standard batching dispensers
Limitations & considerations
- Optimum dosage varies with cement source, temperature and mix design and must be fixed by site or lab trials
- Overdosing can cause excessive retardation, bleeding or segregation, so batching accuracy matters
- As a water reducer it does not entrain air; a separate air-entrainer is needed for freeze-thaw exposure
- It is not a set accelerator or retarder on its own; timing adjustments need a complementary admixture
- Performance depends on correct dispensing sequence and a minimum 60-second wet mix, which needs plant discipline
- Being a PCE, it can show sensitivity to clay or fines in the aggregate, which may blunt the water reduction
Selection & best practice
Always establish the working dosage by trial before production, starting near the lower end of the 0.2-2.0% (by weight of cement) range and adjusting to hit your target flow and strength. Dispense it into the mixer after 50-70% of the mixing water has gone in, rather than onto dry cement or aggregate, and give the batch a minimum 60 seconds of wet mixing so the polymer fully disperses. Keep the total water-cement ratio under control, since the point of the admixture is to remove water, not to add it back once flow looks good. Do not blindly increase dosage to chase workability late in a batch; that is where over-retardation and segregation start. Where a mix will face freeze-thaw or aggressive exposure, pair it with the right air-entraining or corrosion-protection product rather than relying on the superplasticiser alone. Store drums dry between +10°C and +40°C, out of direct sunlight and frost, and use within the 12-month shelf life.
Specifications
| Product type | High-range water-reducing superplasticiser (PCE) |
| Chemical base | Aqueous solution of modified polycarboxylate |
| Appearance | Brown liquid |
| Density | Approx. 1.12 kg/l at 25 C |
| Dosage | 0.2-2.0% by weight of cementitious material |
| Standards | IS 9103; ASTM C494 |
| Packaging | 255 kg drums or bulk supply |
| Shelf life | 12 months from production in sealed, undamaged packaging |
| Storage | Dry, +10 C to +40 C, protected from sunlight and frost |
Industry use cases
Ready-Mix Concrete Producers
Holds slump through long summer hauls across Delhi NCR, so loads arrive placeable without site water addition that would wreck the water-cement ratio.
Precast & Prestressed Yards
Delivers high early strength and dense, blemish-free faces for beams, panels and hollow-core units, speeding up form turnaround.
High-Rise & Infrastructure
Enables pumpable, self-compacting mixes for congested columns, cores, rafts and deep foundations where vibration access is poor.
Commercial & Industrial Slabs
Produces flowing, low-shrinkage floor concrete that spreads and finishes evenly over large pours with reduced labour.
Durability-Critical Structures
Low water-cement ratio mixes give the dense, low-permeability concrete needed for water-retaining and marine or aggressive-exposure work.
Frequently asked questions
What is the correct dosage of Sika ViscoCrete-2004 NS?
How is it added to the concrete mix?
Which standards does it comply with?
Can it be used for self-compacting concrete?
What pack sizes are available and how long does it keep?
Does it entrain air or protect against freeze-thaw?
How we position Sika ViscoCrete-2004 NS
Sika ViscoCrete-2004 NS sits in the general-purpose, workability-retaining band of Sika’s PCE range and is the sensible default for most structural and ready-mix work. Where a project needs a sharper performance profile, the wider Sika ViscoCrete family offers alternatives, such as higher early-strength grades for fast precast demoulding or hot-weather variants with extended retention, and Space Arc can advise on the closest match. For freeze-thaw or aggressive exposure, pair it with a Sika air-entraining admixture rather than pushing dosage. Buyers who standardise on a single brand family may prefer the equivalent Fosroc option below; Space Arc supplies both Sika and Fosroc, so the choice can follow your approved-vendor list rather than availability.
Fosroc Auramix 400 — A specifier already standardised on Fosroc’s admixture range may prefer Auramix 400, a comparable PCE high-range water reducer for self-compacting and pumped concrete, to keep a single approved-vendor supply chain.
Related Concrete Admixtures products
Source Sika ViscoCrete-2004 NS for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.