Fengfan CAS 1965-29-3 2-(2-(2-Aminoethylamino)Ethylamino)Ethanol (NDE)

Product Overview

NDE, or 2-(2-(2-aminoethylamino)ethylamino)ethanol, is the coordination agent that keeps zinc and nickel arriving at the part together in a zinc nickel plating bath. Its short chain carries three nitrogen functions and a terminal hydroxyl, which let it hold both metal ions in the same complex and bring their deposition potentials close enough that the two metals co-deposit as an alloy instead of separating into a zinc-rich layer with nickel-rich patches. That is the point of the product: nickel content stays even from the outside of a rack to the bottom of a recess, and the deposit passivates to one colour rather than several. In the drum it is a colourless to yellowish viscous liquid, assayed by amine value rather than by percentage, and it is dosed into either an alkaline or an acid zinc-nickel system as one component of the additive package, not as a stand-alone brightener.

In the additive package

Most plants buy it as one line item among the coating production chemicals they keep for a zinc-nickel line: a brightener, a carrier, a purifier, a passivation stage and the coordination agent. NDE is rarely the component that decides how bright the deposit looks; it is the one that decides how evenly the alloy is distributed, and the brightness, the colour after passivation and the salt spray result all rest on that. It is supplied from Wuhan through our export desk and through specialist chemical distributors, so buyers who normally source bath components through a regional supplier can ask us which route applies to their market.

Specifications

Defined Chemical Structure for Reliable Application

• Amine value 760±10 mgKOH/g: NDE is assayed by amine value instead of a percentage, so this is the figure to titrate when a drum of plating chemicals arrives. Compare it with the window before the drum goes on the line, because a drift here shows up later as a slow change in nickel content that is hard to trace back.
• Proportion 1.00–1.05 at 25 °C: dosing a viscous liquid by weight is more repeatable than dosing by volume, and this range tells you what a measured litre should weigh when you cross-check a drum or verify a make-up calculation.
• Moisture below 1%: water is the one component that can dilute the active amine without showing on the outside of a drum, which is why the limit is written into the specification. Keep drums sealed between draws and store them in a cool, dry place.
• Molecular weight 147.22: a small molecule with three nitrogen functions and a terminal hydroxyl moves quickly through the bath and coordinates zinc and nickel without adding bulk to the deposit.
• Colour from colourless to yellowish: the shade drifts inside the specification and is not a quality signal on its own, so judge a lot on its amine value and moisture rather than on the tint you see through the drum.
• A structure you can plan around: the chemistry is the same from lot to lot, which is what makes an addition rate worth recording when you balance several coating chemicals against each other.

Role in Zinc-Nickel Plating Baths

Coordination is the quiet half of alloy plating. In a bath bought as a set of coating production chemicals, the brightener gets the credit for the finish, but the alloy ratio comes from the complexing system: NDE binds zinc and nickel ions, moderates how quickly each one discharges at the cathode, and keeps the two from separating. Without that control, nickel tends to fall away in low-current-density areas and pile up where the current is strongest, which is exactly where a rack shows its worst parts.

What changes on the part

The difference appears first in the areas a Hull cell panel would flag: recesses, the inside of a tube, the shadow side of a bracket. With NDE in the package, nickel content across that range moves closer together, so the trivalent chromium colour after passivation comes out even rather than patchy and the corrosion result follows the alloy rather than the most heavily covered patch. Bath behaviour improves as well, because a coordinated solution tolerates small shifts in temperature and current better than an unbalanced one, which reduces the scatter that ends a shift as rejects. Where a line already runs a stable set of coating chemicals and only the alloy consistency is drifting, the coordination agent is the first component worth checking.

Trialling NDE in an Existing Bath

1. Start from what the bath already is: alkaline or acid zinc-nickel, and which plating chemicals it currently runs — brightener, carrier, purifier and the rest. NDE goes into a working system, so the trial has to be measured against that system rather than against a fresh make-up.
2. Record a baseline before anything is added: nickel content at high and low current density, appearance after passivation, and the titration figures your laboratory already tracks.
3. Add the product at the rate your own formulation calls for. If you are building a bath around it rather than topping one up, confirm the starting concentration with our technical desk before the first addition.
4. Run the same parts or coupons again and compare the low-current-density areas against the baseline first — that is where a coordination change shows up before it shows anywhere else.
5. If the line also runs an electroless nickel plating step, evaluate the two separately. The same coordination behaviour helps there, but the baths are controlled on different numbers and a mixed trial tells you nothing.
6. Log the addition rate and retitrate at your normal interval. Once the nickel distribution repeats across two or three lots, the rate is worth fixing as part of the standard plating process, and the next decision becomes replenishment rather than selection.

Applications

• Alkaline zinc-nickel rack lines: automotive fasteners, brackets and chassis hardware where the alloy ratio has to hold across a full load. The coordination agent keeps nickel content from drifting between the top of the rack and the bottom.
• Acid zinc-nickel systems: the same job in a different electrolyte. Acid baths coordinate differently, so the addition rate is set for that system instead of being carried over from an alkaline line.
• Barrel plating of small parts: screws, clips and terminals tumble through a constantly changing current path, which is the kind of plating process where a coordination agent earns its place — the alloy has less chance to even out through geometry alone.
• Deep recesses and low-current-density areas: these are the places where nickel normally drops out first. If rejects cluster in shadowed areas, the coordination balance is the first thing to review.
• Work that is passivated after plating: an even alloy takes a more even trivalent chromium colour, so parts judged on appearance after passivation benefit before any corrosion test is run.
• Electroless nickel plating and aluminium parts: the product is also used where nickel has to build evenly on complex shapes and on aluminium, supporting adhesion and thickness uniformity rather than alloy ratio.

Ordering & Delivery

Technical Support & Model Matching

Choosing the right match is where most sourcing decisions stall. As a trading supplier, we keep one point of contact from first enquiry to after-sales: tell us what you are making and the conditions you work under, and we shortlist the closest matches from our supplier network, compare specifications and arrange samples before you commit to a bulk order. If something does not behave as expected, we work with the supplying partner on the cause and a practical fix, and stay with the case until it is settled. Email, WeChat or WhatsApp enquiries get a reply within 24 hours.

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