MSE PRO PEI-70K Polyethyleneimine, 25 kg/Barrel
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MSE PRO PEI-70K Polyethyleneimine, 25 kg/Barrel
Introduction
Polyethyleneimine (PEI) | PEI-70K is a highly cationic, water-soluble polymer with the highest cationic charge density among organic polymers (CAS No. 9002-98-6), supplied as a 50% w/v aqueous solution of branched Polyethyleneimine with an average molecular weight of 70,000. The polymer consists of repeating ethyleneimine units with the general formula (CH2CH2NH)n and appears as a colorless to pale yellow viscous liquid with a slight ammonia-like odor.
Due to Polyethyleneimine PEI-70K's branched structure and high density of primary, secondary, and tertiary amine groups, PEI-70K exhibits strong cationic charge, excellent adsorption capability, and outstanding molecular bridging performance. It can interact with hydroxyl, carboxyl, carbonyl, and other functional groups via hydrogen bonding, ionic interaction, or covalent bonding, making it highly effective in applications such as water treatment, papermaking, coatings, adhesives, and surface modification.
Key Features
- High Cationic Charge Density: Polyethyleneimine PEI-70K exists in aqueous systems as a strongly cationic polymer, capable of rapidly neutralizing negatively charged surfaces such as fibers, fillers, pigments, colloids, and suspended solids. Compared with lower molecular weight grades, it provides stronger charge neutralization and electrostatic attraction, especially suitable for demanding systems.
- Excellent Bridging and Flocculation Efficiency: The high molecular weight and extended polymer chains allow PEI-70K to form effective molecular bridges between particles, fibers, or fillers. This results in larger, stronger, and more stable flocs, significantly improving retention, sedimentation, drainage, and filtration performance.
- High Chemical Reactivity: Rich in primary and secondary amine groups, PEI-70K readily reacts with epoxies, aldehydes, isocyanates, and other active functional groups. It is suitable for crosslinking modification, resin curing, functional finishing, and chemical adsorption applications.
- Enhanced Adhesion and Interfacial Bonding: Due to its high polarity and multi-functional structure, PEI-70K strongly improves adhesion to polar substrates such as metals, cellulose, inorganic fillers, and mineral surfaces, making it an effective adhesion promoter and surface treatment agent.
Specifications
| Property | Specification |
|---|---|
| Appearance | Colorless or pale yellow liquid |
| Molecular Weight | 70,000 |
| Specific Gravity (25 °C) | 1.05 |
| Viscosity (mPa·s) | 10,000 – 20,000 |
| Resin Content | 50% |
| Amine Value | 10 |
| Flash Point | 300 °C |
| pH | 10 – 12 |
Application Areas
1. Paper and Pulp Chemicals
PEI-70K is widely used as a high-efficiency retention aid, drainage aid, and dry-strength agent in papermaking. Its strong cationic charge rapidly neutralizes anionic pulp fibers and fillers, while the long molecular chains provide superior bridging between fines and fillers. This leads to significantly improved retention, faster dewatering, and enhanced sheet formation. In dry-strength applications, PEI-70K forms extensive hydrogen-bonding networks with cellulose, maintaining paper strength even at high filler loading.
2. Water and Wastewater Treatment
In industrial and municipal wastewater treatment, PEI-70K functions as a high-performance flocculant or coagulant aid. It efficiently destabilizes colloidal systems by charge neutralization and molecular bridging, forming large, porous flocs that settle rapidly and filter easily. The amine groups also chelate heavy metal ions, making PEI-70K especially effective for treating wastewater containing metals, pigments, or fine suspended solids.
3. Coatings and Inks
In water-based coatings and inks, PEI-70K can be used as a strong pigment anchoring agent or dispersion aid. Its cationic amine groups adsorb firmly onto pigment surfaces, improving dispersion stability and preventing re-agglomeration under high solids or high pigment loading. Additionally, PEI-70K can enhance interfacial adhesion between pigments and binder resins, improving coating integrity and print durability.
4. Adhesion Promotion and Surface Treatment
PEI-70K serves as an effective adhesion promoter for metals, glass, concrete, and other polar substrates. The amine groups interact with metal oxides or inorganic surfaces, while the polymer backbone entangles or reacts with coating or adhesive resins, forming a robust interfacial bonding layer that improves wetting, adhesion strength, and long-term durability.
5. Adhesives and Resin Modification
In adhesive and resin systems, PEI-70K can act as a reactive crosslinker or functional modifier. Its high amine functionality enables efficient crosslinking with epoxy and other reactive resins, increasing cohesive strength, chemical resistance, and adhesion performance. The higher molecular weight provides strong reinforcement without excessive brittleness when properly formulated.
6. Textiles, Nonwovens, and Functional Finishing
In textile and nonwoven processing, Polyethyleneimine PEI-70K is used for dye fixation, surface functionalization, and antistatic finishing. Its strong cationic nature enhances binding with anionic dyes, improving color fastness, while its hydrophilic structure contributes to moisture management and antistatic properties. It is also applicable in functional and medical nonwoven materials.
Storage & Handling Precautions
Recommended Conditions: Low temperature (<25°C; long-term storage recommended at 4–10°C refrigeration), light-proof, dry, and sealed environment.
High-Temperature Risk: Storage above 80°C or exposure to air may cause oxidation, discoloration (darkening), surface skinning, severely degrading performance (e.g., reduced amine value, weakened viscosity).
Hygroscopicity: Polyethyleneimine PEI-70K is hygroscopic and absorbs CO2; containers must be tightly sealed to avoid contact with moist air (otherwise, salts may precipitate or the product may fail).
MSE Supplies offers various water-based resins, please contact us to discuss your needs.