Sodium Polyaspartate (CAS 35608-40-6), chemically identified as the sodium salt of polyaspartic acid, is a biodegradable polymer functioning as a green scale inhibitor and dispersant in industrial water treatment and agricultural nutrient enhancement. This water-soluble polypeptide, widely technically referred to as PASP, acts as a non-phosphorus alternative to traditional polyacrylates, effectively preventing calcium carbonate and calcium sulfate scale formation in cooling towers and reverse osmosis systems. HPMA is another polymeric scale inhibitor and dispersant for high-temperature water systems. We provide bulk supply of this eco-friendly functional polymer with competitive factory pricing to promote sustainable chemical management. Our synthesis process ensures specific molecular weight distribution, making MSDS, TDS, COA available alongside customized specifications (Liquid 40% / Powder) to meet green chemistry standards.
Sodium Polyaspartate (PASP) CAS 35608-40-6
- CAS: 35608-40-6
- Synonyms: Sodium Polyaspartate, Polyaspartic acid sodium salt, PASP, Sodium salt of polyaspartic acid, Biodegradable scale inhibitor
- Einecs: 639-847-1
- Molecular Formula: (C4H4NO3Na)n
- Grade: Industrial Grade / Water Treatment Grade
- Package: 25 kg / 250 kg plastic drums or 1000 L IBC totes (custom packaging on request)
Product Description
PASP is produced by polymerization of aspartic acid and subsequent neutralization with sodium. The polymer chain is rich in carboxyl and amide groups, which gives it strong chelating and dispersing power, high thermal stability in water systems, and excellent biodegradability.
As a new-generation eco-friendly water treatment agent, Sodium Polyaspartate can partially or completely replace traditional phosphonate and polyacrylate antiscalants, helping end users reduce phosphate discharge and the risk of eutrophication while keeping heat-exchange surfaces clean and efficient.
Physicochemical Properties
| Property | Typical Value |
|---|---|
| Appearance | Yellow to amber clear liquid |
| Chemical nature | Sodium salt of polyaspartic acid, polyanionic polymer |
| CAS No. | 35608-40-6 |
| Einecs No. | 639-847-1 |
| Solid content | ≥ 40.0 wt% |
| Density (20 °C) | ≥ 1.20 g/cm³ |
| pH (1% aqueous solution, 25 °C) | 9.0 – 11.0 (alkaline) |
| Average molecular weight (Mw) | approx. 1,000 – 5,000 |
| Solubility | Completely soluble in water |
| Biodegradability | Fully biodegradable, phosphorus- and nitrogen-free |
| Thermal stability (in solution) | Stable under normal circulating water conditions |
| Main functional groups | Carboxyl (–COO⁻), amide (–CONH–) |
| Chelation / dispersion | Strong chelation with Ca²⁺, Mg²⁺, Fe²⁺/Fe³⁺ etc.; excellent dispersion of inorganic scale |
Note: Values above are typical data, not guaranteed specifications. Custom specifications can be supplied according to client requirements.
Applications
1. Industrial Water Treatment
- Circulating cooling water & open recirculating systems – Acts as a non-phosphorus scale and corrosion inhibitor for CaCO₃, CaSO₄, BaSO₄ and Ca₃(PO₄)₂ scales, maintaining heat-exchange efficiency.
- Boiler water, RO and desalination systems – Controls hardness scale and dispersed iron, reduces cleaning frequency and extends membrane/equipment life.
- High-hardness & high-alkalinity systems – Shows good performance at high cycles of concentration where conventional agents fail.
2. Oilfield & Drilling
- Used as a corrosion inhibitor and scale inhibitor in oilfield injection water and produced-water re-injection systems.
- As a viscosity reducer / dispersant in drilling fluids, helps to thin bentonite mud and improve rheology.
3. Detergent & Cleaning Formulations
- Functions as a biodegradable builder and dispersant in household and industrial detergents, dishwashing liquids and hard-surface cleaners.
- Helps soften water, disperse soil, prevent re-deposition and improve overall cleaning performance.
4. Agriculture & Forestry
- Used as a fertilizer synergist / soil conditioner to improve nutrient availability and uptake of N, P, K and trace elements.
- Can enhance plant stress resistance and yield when combined with fertilizers or certain pesticides.
5. Other Uses
- Dispersant or chelating agent in pigments, coatings, leather, paper, and inorganic chemicals.
For detailed formulation suggestions in your specific system, please contact: info@industrochem.com.
For related water-treatment scale-control raw materials, see HPMA and HEDP.
Storage Conditions
- Store in tightly closed original containers.
- Keep in a cool, dry, well-ventilated warehouse, away from direct sunlight and heat sources.
- Recommended storage temperature: 5 – 35 °C; avoid freezing.
- Under proper storage conditions, typical shelf life is about 10–12 months from production date.
If product is stored beyond the recommended period, re-test key parameters before use.
Safety Precautions
- Alkaline liquid; avoid contact with eyes, skin and clothing.
- Wear suitable protective gloves, goggles and protective clothing when handling.
- In case of contact with skin or eyes, rinse immediately with plenty of clean water and seek medical advice if irritation persists.
- Do not ingest. If swallowed, rinse mouth and seek medical attention.
- Do not discharge large quantities into surface water or sewage systems; follow local environmental regulations.
- Refer to the detailed SDS/MSDS for complete safety and handling information.
FAQ - Technical & Supply Chain
-
Q:
What is Sodium Polyaspartate CAS 35608-40-6?
A: Sodium polyaspartate, commonly called PASP, is a water-soluble polyamide polymer derived from aspartic acid. It is used as a biodegradable, phosphorus-free antiscalant, dispersant and chelating agent. -
Q:
Why does this product also appear under CAS 181828-06-8?
A: Sodium polyaspartate is listed by multiple CAS numbers depending on the registry source and salt representation. CAS 181828-06-8 is a common alternative to 35608-40-6 for the same sodium salt of polyaspartic acid, so both numbers may appear on technical documents. -
Q:
What environmental advantage does PASP offer over phosphonate antiscalants?
A: PASP is phosphorus-free and readily biodegradable, so it does not contribute the same eutrophication risk associated with many phosphonate scale inhibitors. This makes it suitable for environmentally sensitive water-treatment programs. -
Q:
What are the main applications?
A: Typical uses include cooling-water and boiler-water scale inhibition, reverse-osmosis systems, seawater desalination, industrial cleaning, detergent formulations and agricultural nutrient systems where mild metal chelation or dispersion is needed. -
Q:
Why is PASP used as a fertilizer synergist?
A: PASP can chelate micronutrients and help keep them available to plants, while its dispersing behavior may slow crystallization or precipitation of nutrients in soil or fertilizer solutions. Agronomic use should follow local fertilizer regulations and trial results. -
Q:
Which grade and packaging are available?
A: The listing is industrial/water-treatment grade and is supplied in 25 kg or 250 kg plastic drums or 1000 L IBC totes. Custom packaging can be arranged on request. -
Q:
What specifications should be checked before ordering?
A: Confirm active-polymer or solids content, molecular-weight range, pH, density, viscosity, residual monomer and application-specific performance. Request the current batch analysis, technical data and safety information before purchase. -
Q:
How should sodium polyaspartate be stored and handled?
A: Store in closed compatible containers in a cool, dry, ventilated area away from strong oxidizers and incompatible materials. Avoid freezing and excessive heat, use chemical-resistant gloves and eye protection, and follow the safety information.
Ordering & Documentation
Key information for document requests, quotations, and supply planning.
Documents
COA, TDS, SDS/MSDS and packing details are available on request.
Quotation
Send the CAS number, grade, quantity, packing preference and destination.
Sample & Supply
Support is available for samples, trial orders, bulk and repeat supply.
Storage & Shipping
Product-specific conditions are confirmed before order.
