Properties and Applications of KR-499 Acrylic/Sulfonic Terpolymer

KR-499 (Acrylic/Sulfonic Terpolymer) is a high-performance water treatment polymer designed for demanding industrial water systems. By incorporating acrylic acid, sulfonic acid monomers, and a non-ionic monomer into its chemical backbone, KR-499 provides h3 threshold scale inhibition, crystal distortion, and particulate dispersancy—even under extreme conditions (high hardness, high alkalinity, high temperature, and high iron content).

Technical Specifications

Parameter Specification

Chemical Structure Acrylic Acid / Sulfonic Acid / Non-Ionic Terpolymer

Appearance Clear, pale yellow liquid

Solid Content ~40% (typical)

pH (1% aqueous solution) 2.5 – 4.5

Viscosity (25°C) 20 – 100 mPa·s

Solubility Fully soluble in water across all ratios

Key Functional Properties

1. Calcium Phosphate & Zinc Stabilization

Phosphate Inhibition: Prevents calcium phosphate (Ca3(PO4)2) precipitation, which is crucial in high-phosphate cooling water treatments.

Zinc Solubilization: Maintains soluble Zn2+ in solution at elevated pH levels ($pH > 8.0$), preventing zinc hydroxide precipitation and enhancing zinc-based corrosion inhibition formulations.

2. High Tolerance to Harsh Water Quality

Hardness & Alkalinity: Operates effectively at high cycles of concentration where calcium hardness ($Ca^{2+}$) and bicarbonate/carbonate alkalinity are significantly elevated.

Halogen Stability: Shows excellent resistance to degradation by oxidizing biocides (free chlorine, bromine, hypochlorite, and ozone).

3. Iron Oxide & Silt Dispersancy

Converts rigid particulate deposits (like Fe2O3, mud, clay, and inorganic sludge) into negatively charged particles that repel each other, keeping heat exchange surfaces clean and free of bio-sludge/silt accumulation.

4. Crystal Modification & Threshold Inhibition

Inhibits the nucleation and growth of calcium carbonate (CaCO3) and calcium sulfate (CaSO4) crystals. The incorporated sulfonic group deforms the crystal lattice structure, causing scale to form as loose, non-adherent sludge rather than hard scale.

Primary Applications

Industrial Recirculating Cooling Water: Core dispersant for open and closed recirculating cooling towers, particularly in high-alkalinity, high-phosphate, or zinc-stabilized programs.

Boiler & Steam Systems: Controls sludge accumulation and phosphate/silicate deposition in low-to-medium pressure boiler feed water.

Reverse Osmosis (RO) Antiscalant Formulations: Blended into RO membrane pretreatment chemicals to prevent foulants (silicate, iron, and phosphate scales) from blinding membranes.

Oilfield Reinjection Water: Used to disperse inorganic scales and particulate matter in geothermal and oilfield water systems under high salinity and pressure.

Textile & Printing Auxiliaries: Functions as a chelating and dispersing agent in textile pre-treatment and dyeing baths.

Formulation Tip: KR-499 is highly compatible with organophosphonates (such as PBTC, HEDP, ATMP) and azoles (BTA/TTA). Typical continuous dosage in cooling water circuits ranges from 5 to 20 mg/L (active polymer) depending on water quality and concentration cycles.