Production Process of Construction-Grade Starch Ether
Construction-Grade Starch Ether | Applications Tile Adhesives (anti-sag) Putty (thickening & water retention) Gypsum Mortars (workability enhancement)
Production Process of Construction-Grade Starch Ether
1.Raw Material Preparation
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Starch Treatment:
Selected cassava is sieved to remove impurities and mixed into a 30%~40% starch slurry. -
Alkaline Activation:
Sodium hydroxide (NaOH) solution is added to adjust pH to 10~12, ionizing hydroxyl groups of starch molecules at 40~50°C.
2. Etherification Reaction
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Etherifying Agent Addition:
Etherifying agent (e.g., sodium chloroacetate) is added at 5%~15% of starch dry weight, with slow dripping under constant stirring. -
Constant-Temperature Reaction:
Reaction proceeds at 40~60°C for 2~5 hours to form sodium starch ether.
3. Post-Treatment
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Neutralization:
Hydrochloric acid (HCl) or acetic acid is used to neutralize pH to 6.5~7.5, stopping the reaction. -
Washing & Purification:
By-products (e.g., NaCl) are removed by centrifugation, followed by repeated washing with deionized water until conductivity <100 μS/cm. -
Drying:
Flash drying or spray drying reduces moisture content to ≤10%.
4. Product Formulation
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Milling & Sieving:
Dried product is micronized and sieved through 200-mesh for uniform particle size. -
Blending (Optional):
Blended with cellulose ether or air-entraining agents for enhanced performance in specific applications.
5. Packaging & Quality Control
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Packaging:
Moisture-proof aluminum foil or woven sacks, 25kg/bag. -
QC Parameters:
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Degree of Substitution (DS): 0.02~0.10
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Viscosity (2% solution): 100~5000 mPa·s
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Ash content ≤5%, pH 6~8
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| Applications
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Tile Adhesives (anti-sag)
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Putty (thickening & water retention)
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Gypsum Mortars (workability enhancement)
| Safety & Environmental
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Wastewater Treatment: Salt-containing wastewater undergoes evaporation-crystallization for NaCl recovery.
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Exhaust Control: Drying exhaust is filtered via bag dust collectors before emission.
This process meets the requirements of low viscosity, high water retention, and mildew resistance for construction-grade starch ether, suitable for continuous industrial production.