FREQUENTLY ASKED QUESTIONS

Polycarboxylate superplasticizer is a high-performance admixture for modern construction. It is used to reduce water in concrete while improving flowability, strength, and durability, key for high-performance, self-compacting, and durable concrete in modern construction.

1. High Water Reduction – It significantly lowers the water-cement ratio (up to 40%) without sacrificing workability, enhancing strength and durability.
2. Superior Workability – PCE provides excellent slump retention, ideal for self-compacting concrete and long-distance pumping.
3. Enhanced Strength & Durability – It reduces porosity and improves resistance to freeze-thaw, chloride ingress, and chemical attacks.
4. Controlled Setting Time – It can be tailored for fast or delayed hardening, useful for hot/cold weather concreting.
5. Eco-Friendly – It reduces cement usage, lowers CO₂ emissions, and supports sustainable construction.

For optimal performance, silicone hydrophobic powder should be stored in a cool, dry environment with temperatures not exceeding 30°C (86°F). It must be protected from humidity and direct sunlight exposure. After each use, ensure the packaging is securely resealed to prevent moisture absorption.

The defoaming rate of powder defoamers is influenced by multiple factors, including material properties, environmental conditions, and application methods. Here are the key factors:
1. Particle Size: Finer particles disperse better, improving defoaming efficiency.
2. Hydrophobicity: Higher hydrophobicity enhances antifoaming but may reduce compatibility.
3. Temperature: The Optimal range is 10–60°C (depending on carrier material). Excessive heat may degrade active components.
4. Storage Conditions: Moisture absorption reduces effectiveness (stored in dry, sealed containers). Long-term storage may cause settling or clumping.
5. Carrier Material: Silica, calcium stearate, or starch-based carriers affect the release rate.

When using a powder defoamer, ensure proper storage in a dry, cool environment to prevent moisture absorption and clumping. Disperse evenly during mixing to avoid uneven performance, and adjust the dosage based on foam severity. Consider pH and temperature stability, as extreme conditions can reduce effectiveness. Always conduct small-scale tests before full application to optimize compatibility and defoaming efficiency. Seal the packaging tightly after each use to maintain shelf life and performance.

Gypsum retarders are compatible with accelerators, water reducers, air entrainers, bonding agents, and fibers. For optimal performance verification, LANDU NOVASTAR can conduct small-batch compatibility testing and provide a detailed report to support your formulation decisions.

Amino-based gypsum retarders, typically derived from organic amino acids or proteins, offer enhanced retardation efficiency, better stability under varying temperatures, and improved compatibility with other admixtures compared to traditional retarders. They provide more precise setting control, reduced strength loss, and lower dosage requirements, making them ideal for high-performance gypsum applications like precision casts or self-leveling underlayments.

There are several key factors to notice during the use of gypsum retarders for gypsum-based self-leveling compounds.

• Adaptability test
  – Conduct small sample tests first to verify the compatibility of the retarder with systems such as gypsum, water reducers, and defoamers, to prevent abnormal setting or strength loss.
• Precisely control dosage
  – The recommended dosage is 0.01%~0.3% (adjusted by specific types), and an overamount will lead to too long a final setting time, decreased strength, and chalking of surfaces.
• Construction environment
  – The dosage of gypsum retarder should be increased in high-temperature conditions (lower than the threshold value) and decreased in low-temperature conditions to avoid excessive delayed hardening.
• Synergistic with other admixtures
  – When compounded with polycarboxylate superplasticizer, attention should be paid to charge matching to prevent flocculation.

Notes: If bleeding or stratification occurs, the type of retarder or the gradation can be adjusted or optimized. Welcome to contact LANDU NOVASTAR to get your customized formula support.