HYDROXYALKYLAMIDE (HAA) RESIN

Hydroxyalkylamide (HAA) Resin is the common trade name of β-hydroxyalkylamide crosslinkers, the most widely used of which is N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide (CAS No 6334-25-4, C14H28N2O6), a white powder hardener that cures carboxyl-functional polyester resins in thermosetting powder coatings and is the main TGIC-free curing agent for outdoor-durable polyester powders.
The HAA crosslinker is preferred in powder coatings because it reacts readily with carboxyl groups without a catalyst, gives coatings with good weathering resistance, gloss retention, flexibility and adhesion, and allows formulators to replace triglycidyl isocyanurate (TGIC), which carries a severe hazard classification in the European Union.
The beta-hydroxyalkylamide hardener works through its four β-hydroxyl groups, which esterify the acid end groups of the polyester during baking, building a densely crosslinked polyester network and releasing water as the only by-product.

CAS No: 6334-25-4
EC No: 405-370-0
Molecular formula: C14H28N2O6
Molecular weight: 320.38 g/mol
Appearance: White to off-white fine powder
Melting range: approx. 115–130 °C
Hydroxyl equivalent weight: approx. 80–90 g/eq
Density: approx. 1.24 g/cm³
Volatile content: typically ≤ 0.1 %

COMMON PRODUCT & CHEMICAL NAMES OF HYDROXYALKYLAMIDE (HAA) RESIN:

Hydroxyalkylamide (HAA) Resin, Hydroxyalkylamide, Hydroxyalkyl Amide, HAA, β-Hydroxyalkylamide, Beta-Hydroxyalkylamide, HAA Crosslinker, HAA Curing Agent, HAA Hardener, N,N,N',N'-Tetrakis(2-hydroxyethyl)adipamide, N,N,N',N'-Tetrakis(2-hydroxyethyl)hexanediamide, Hexanediamide, N,N,N',N'-tetrakis(2-hydroxyethyl)-, Tetrakis(hydroxyethyl)adipamide, TGIC-Free Curing Agent, Non-TGIC Crosslinker, Polyester Powder Coating Crosslinker, Primid XL-552, Primid QM-1260, Acetomer 552

The name "Hydroxyalkylamide (HAA) Resin" is widely used in the powder coating trade even though the product is not a resin in the strict sense but a low-molecular-weight crosslinker (hardener). β-Hydroxyalkylamide and HAA describe the chemical class. N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide is the chemical name of the most common HAA. Primid XL-552 and Acetomer 552 are trade names of this substance, while Primid QM-1260 refers to a related hydroxypropyl-type HAA with somewhat different reactivity and handling.
The HAA curing agent should not be confused with TGIC (triglycidyl isocyanurate, CAS 2451-62-9), the epoxy crosslinker it replaces, or with carboxyl polyester resins, which are the binders it cures. Different HAA products can have different CAS numbers, hydroxyl equivalent weights and recommended ratios, so the exact grade must always be specified.

WHAT IS HYDROXYALKYLAMIDE (HAA) RESIN?

The beta-hydroxyalkylamide hardener belongs to the class of β-hydroxyalkylamides: amides in which the nitrogen atoms carry hydroxyalkyl groups whose hydroxyl group sits on the carbon two positions away from the nitrogen (β-position). This specific position is what makes the hydroxyl groups unusually reactive toward carboxylic acids.
The most important commercial HAA is N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide. It is made by reacting an adipic acid ester (such as dimethyl adipate) with diethanolamine. Each of the two amide nitrogens carries two 2-hydroxyethyl groups, giving four reactive hydroxyl groups per molecule. With a molecular weight of about 320 g/mol, this corresponds to a theoretical hydroxyl equivalent weight of about 80 g/eq.

The HAA curing agent is supplied as a fine, white to off-white crystalline powder with a melting range of roughly 115–130 °C. It is hygroscopic and should be kept dry. Because it is used in small amounts, homogeneous distribution in the premix and during extrusion is essential.
Some suppliers offer HAA products in different forms, for example micronized, granulated or as masterbatch in polyester, to improve dosing and dispersion. Related hydroxypropyl-type HAA grades are also on the market, they react somewhat differently and may offer advantages in degassing or yellowing behavior.

In a polyester powder coating, the binder consists of two components: a carboxyl-functional polyester resin and a crosslinker. The HAA crosslinker is that crosslinker. It is premixed with the polyester, pigments, fillers and additives, extruded, ground into powder and applied electrostatically. In the oven, the powder melts, flows and cures as the hydroxyl groups of the HAA react with the polyester's carboxyl groups.
Because the HAA molecule is small and highly functional, only a few percent are needed. In typical formulations, the polyester-to-HAA ratio is around 95:5 to 96.5:3.5 by weight, depending on the acid value of the polyester. Standard HAA polyesters are designed to cure in about 10 minutes at 160–180 °C object temperature, and many systems also allow slower or lower-temperature schedules.

The main reason for the growth of Hydroxyalkylamide (HAA) Resin is regulation. TGIC is classified in the EU as a mutagen and toxic substance, which led most European powder coating producers to switch to TGIC-free systems. HAA-cured polyester powders became the standard replacement for exterior applications.
For end users, Hydroxyalkylamide (HAA) Resin makes it possible to produce durable, weather-resistant powder coatings for aluminum profiles, façades, garden furniture, agricultural equipment and many other outdoor metal parts, with good gloss retention, color stability and mechanical properties.
For formulators, HAA offers uncatalyzed curing, good flow, good overbake behavior in electric ovens, flexibility in gloss and texture design, and compatibility with many standard and super-durable polyester resins.

CAS NO, EC / EINECS NO AND CHEMICAL IDENTIFICATION OF HYDROXYALKYLAMIDE (HAA) RESIN

PRODUCT NAME: HYDROXYALKYLAMIDE (HAA) RESIN
Common abbreviation: HAA
Chemical name: N,N,N',N'-Tetrakis(2-hydroxyethyl)adipamide (hexanediamide, N,N,N',N'-tetrakis(2-hydroxyethyl)-)
CAS No: 6334-25-4
EC No: 405-370-0
Molecular formula: C14H28N2O6
Molecular weight: 320.38 g/mol
Chemical class: β-Hydroxyalkylamide, tetrafunctional hydroxy-amide crosslinker
Main functions: Crosslinker (hardener) for carboxyl-functional polyester powder coatings, TGIC replacement

The identification data above refer to the most common HAA, tetrakis(2-hydroxyethyl)adipamide. Other HAA types are chemically different and have their own CAS numbers, so the CAS number on the product documents should be checked against the grade being purchased.
The HAA crosslinker is an industrial raw material for coatings. It has no INCI name, no food additive number and no pharmaceutical use.

HOW DOES HYDROXYALKYLAMIDE (HAA) RESIN CURE POLYESTER POWDER COATINGS?

THE CURE REACTION
During baking, each β-hydroxyl group of Hydroxyalkylamide (HAA) Resin reacts with a carboxylic acid end group of the polyester to form an ester bond. The neighboring amide group assists this reaction: it is generally explained by the formation of a short-lived cyclic intermediate (an oxazolinium-type species), which makes the esterification much faster than a normal acid–alcohol esterification. For this reason, HAA cures carboxyl polyesters at typical powder coating temperatures without an added catalyst.

NETWORK FORMATION
Because each HAA molecule carries four reactive hydroxyl groups and each polyester chain carries several carboxyl groups, the reaction builds a three-dimensional polyester network. The density of this network depends on the polyester's acid value and functionality and on the HAA ratio.

BY-PRODUCT
The esterification releases water. In a molten powder film, this water must escape before the film becomes too viscous. If too much water is trapped, it can cause pinholes, blisters or haze, especially in thick films. This degassing behavior is the main technical difference from TGIC, whose epoxy–acid reaction releases no by-product.

STOICHIOMETRY
HAA-cured systems are usually formulated with polyesters of acid value around 30–35 mg KOH/g. The amount of HAA is calculated from the acid value of the polyester and the hydroxyl equivalent weight of the HAA. A slight excess or deficit can be used to adjust properties, but large deviations reduce crosslink density and performance.

THE FUNCTIONS OF HYDROXYALKYLAMIDE (HAA) RESIN IN A POWDER COATING CAN BE SUMMARIZED AS:

CROSSLINKING CARBOXYL-FUNCTIONAL POLYESTER RESINS
Building chemical and solvent resistance
Providing flexibility, impact resistance and adhesion
Supporting outdoor durability and gloss retention
Enabling TGIC-free formulations
Allowing catalyst-free curing at typical powder coating temperatures

HYDROXYALKYLAMIDE (HAA) RESIN IN POWDER COATING FORMULATIONS

A TYPICAL HAA POLYESTER POWDER COATING CONTAINS:

CARBOXYL-FUNCTIONAL POLYESTER RESIN DESIGNED FOR HAA CURE (STANDARD OR SUPER-DURABLE)
Hydroxyalkylamide (HAA) Resin as crosslinker
Pigments (for example titanium dioxide and color pigments)
Fillers (for example barium sulfate)
Flow and leveling agent
Degassing agent (commonly benzoin)
Optional waxes, texture agents, matting agents and other additives

KEY FORMULATION GUIDELINES:

Use polyesters specifically designed for HAA cure, polyesters for TGIC or epoxy hybrids may not give the right reactivity or degassing behavior.
Calculate the HAA level from the polyester acid value and the supplier's recommended ratio.
Include a degassing agent and choose suitable flow additives to support water release.
Keep film thickness within the recommended range, very thick films increase the risk of pinholing.
Check overbake color stability, especially in direct gas-fired ovens, where combustion gases can increase yellowing.
Check storage stability of the powder, because hygroscopic components can lead to clumping.

Hydroxyalkylamide (HAA) Resin-cured polyesters are available in standard and super-durable versions. Super-durable systems are designed for architectural applications that must meet higher façade weathering requirements, such as those specified by architectural powder coating qualification schemes.

IN WHICH SECTORS IS HYDROXYALKYLAMIDE (HAA) RESIN USED?

MAIN AREAS OF USE:

ARCHITECTURAL ALUMINUM PROFILES, WINDOWS, DOORS AND FAÇADE ELEMENTS
Outdoor metal furniture and garden equipment
Agricultural and construction machinery
Automotive accessories and wheels
Fencing, railings and street furniture
Electrical enclosures and outdoor cabinets
General industrial metal parts
Indoor polyester powder coatings where TGIC-free systems are required

The architectural sector values Hydroxyalkylamide (HAA) Resin for long-term weathering and color stability. General industry focuses on fast curing and cost efficiency, while producers of outdoor furniture and equipment look for a balance of durability, flexibility and appearance.

IS HYDROXYALKYLAMIDE (HAA) RESIN USED IN COSMETIC, FOOD, AND PHARMACEUTICAL APPLICATIONS?

No. The beta-hydroxyalkylamide hardener is an industrial crosslinker for coatings. It has no INCI name, no E number and no pharmaceutical use. Powder coatings made with HAA may be used on objects that come into contact with food only if the final coating has been evaluated and declared compliant with the food contact regulations of the target market.

INDUSTRIAL APPLICATIONS OF HYDROXYALKYLAMIDE (HAA) RESIN

ARCHITECTURAL POWDER COATINGS
Purpose: To protect and decorate aluminum and steel building elements for many years outdoors.
Role of Hydroxyalkylamide (HAA) Resin: Crosslinker for standard or super-durable polyesters.
Performance effect: Good gloss retention, color stability and chalking resistance, depending on the polyester and pigments.
Limitations: Requires careful degassing control, film thickness and oven conditions must be optimized.

GENERAL INDUSTRIAL OUTDOOR COATINGS
Purpose: Durable, fast-curing coatings for equipment, machinery and furniture.
Role of Hydroxyalkylamide (HAA) Resin: Catalyst-free crosslinker enabling efficient curing schedules.
Performance effect: Good mechanical properties, adhesion and flexibility.
Limitations: Overbake yellowing in some gas-fired ovens, edge coverage and orange peel should be checked.

TEXTURED, MATT AND SPECIAL-EFFECT POWDERS
Purpose: To provide decorative finishes in TGIC-free systems.
Role of Hydroxyalkylamide (HAA) Resin: Base curing agent combined with texture or matting agents.
Limitations: Matting HAA systems often requires specific additives or dry-blend approaches, results depend strongly on the chosen polyester.

WHICH PROBLEMS CAN HYDROXYALKYLAMIDE (HAA) RESIN HELP SOLVE?

REGULATORY PRESSURE ON TGIC
TGIC's hazard classification creates labeling, occupational exposure and customer acceptance problems. Hydroxyalkylamide (HAA) Resin offers a well-established TGIC-free route for durable polyester powders.

NEED FOR OUTDOOR DURABILITY WITHOUT EPOXY
Epoxy and epoxy-polyester hybrid powders chalk and yellow quickly outdoors. HAA-cured pure polyesters provide much better exterior durability.

CATALYST-RELATED ISSUES
HAA does not require an added cure catalyst, which simplifies formulation and avoids catalyst-related yellowing or storage issues.

MECHANICAL PERFORMANCE
Properly cured HAA polyester coatings provide good flexibility, impact resistance and adhesion on pretreated metal.

These advantages depend on correct formulation and processing, degassing and film thickness must be managed to avoid defects.

THINGS TO CONSIDER WHEN USING HYDROXYALKYLAMIDE (HAA) RESIN

The most frequent problems with Hydroxyalkylamide (HAA) Resin systems are pinholes and blisters caused by the water released during curing. Film thickness, heating rate and degassing additives therefore need special attention.

POINTS TO CONSIDER:

SELECT A POLYESTER DESIGNED FOR HAA CURE.
Calculate the HAA level from the polyester acid value.
Use benzoin or other degassing aids and suitable flow agents.
Keep film thickness within the validated range.
Optimize the heat-up rate and cure schedule of the oven.
Check overbake yellowing, especially in direct gas-fired ovens.
Store HAA and finished powder dry, as moisture can cause clumping and affect reactivity.
Ensure homogeneous premixing and extrusion, since HAA is used at low levels.
Avoid dust formation and use local exhaust ventilation during handling.

Supplier safety data sheets classify tetrakis(2-hydroxyethyl)adipamide with the signal word "Warning", listed hazards vary by supplier and include skin, eye and respiratory irritation or harm if swallowed. Dust should be avoided, and gloves, safety glasses and dust protection should be used during handling.

INITIAL FORMULATION APPROACHES FOR HYDROXYALKYLAMIDE (HAA) RESIN

The examples below illustrate how Hydroxyalkylamide (HAA) Resin can be evaluated in powder coating development. They are starting formulations for laboratory work, not approved commercial products. Polyester, pigment and additive choices, as well as extrusion and baking conditions, can change the results significantly.

The percentage compositions below are illustrative laboratory starting mixtures (% w/w of total powder), not validated commercial recipes. Each totals 100 %. Confirm the HAA ratio from the resin acid value and hardener equivalent weight, then rebalance the full formulation.

EXAMPLE 1: WHITE OUTDOOR POLYESTER/HAA POWDER COATING

Objective: To prepare and test a standard white exterior powder coating based on Hydroxyalkylamide (HAA) Resin.

INITIAL COMPONENTS (PARTS BY WEIGHT):

Carboxyl polyester for HAA cure (acid value approx. 30–35 mg KOH/g): approx. 57
Hydroxyalkylamide (HAA) Resin: approx. 3 (approx. 95:5 polyester:HAA)
Titanium dioxide (exterior grade): approx. 30
Barium sulfate: approx. 8.5
Flow agent: approx. 1
Benzoin: approx. 0.3–0.5

APPLICATION APPROACH:

ALL COMPONENTS ARE PREMIXED THOROUGHLY.
The premix is extruded under conditions that avoid premature reaction.
The extrudate is cooled, crushed, ground and sieved to the target particle size.
The powder is applied electrostatically to pretreated aluminum or steel panels.
Panels are cured, for example at 180 °C object temperature for 10 minutes or according to the polyester supplier's recommendation.
Gloss, appearance, adhesion, impact, flexibility, solvent resistance, overbake color stability and accelerated weathering are evaluated.

ILLUSTRATIVE INITIAL COMPONENTS (% W/W)
Carboxyl polyester for HAA cure: 57.00 %
Hydroxyalkylamide (HAA) Resin: 3.00 %
Exterior-grade titanium dioxide: 30.00 %
Barium sulfate: 8.60 %
Flow agent: 1.00 %
Benzoin: 0.40 %
Total: 100.00 %
This selects a benzoin level within the stated range and adjusts the filler to complete the total.

EXAMPLE 2: HAA STOICHIOMETRY SCREENING

Objective: To determine the optimum Hydroxyalkylamide (HAA) Resin level for a given polyester.

INITIAL APPROACH:

POLYESTER FOR HAA CURE: CONSTANT
Hydroxyalkylamide (HAA) Resin: approx. 4.0, 4.5, 5.0, 5.5 and 6.0 % of the binder
Pigments, fillers and additives: constant

APPLICATION APPROACH:

POWDERS ARE PREPARED AND APPLIED UNDER IDENTICAL CONDITIONS.
Gel time, flow, gloss, mechanical properties and solvent resistance (for example MEK rub test) are compared.
The level giving complete cure and the best balance of properties is selected.

ILLUSTRATIVE COMPONENTS FOR THE 5.0 % HAA-ON-BINDER TRIAL (% W/W OF TOTAL POWDER)
Carboxyl polyester for HAA cure: 57.00 %
Hydroxyalkylamide (HAA) Resin: 3.00 %
Titanium dioxide: 30.00 %
Barium sulfate: 8.60 %
Flow agent: 1.00 %
Benzoin: 0.40 %
Total: 100.00 %
Keep the binder at 60 % of total powder. For HAA levels of 4.0, 4.5, 5.5 and 6.0 % of binder, use respectively 2.40, 2.70, 3.30 and 3.60 % HAA and 57.60, 57.30, 56.70 and 56.40 % polyester in total powder. Other ingredients remain fixed and each trial totals 100 %. This holds the binder total constant while changing its internal ratio.

EXAMPLE 3: FILM THICKNESS AND DEGASSING EVALUATION

Objective: To evaluate the pinhole-free film thickness limit of a Hydroxyalkylamide (HAA) Resin powder and the effect of degassing agent level.

INITIAL APPROACH:

Formulation from Example 1 as base
Benzoin: approx. 0, 0.3, 0.6 and 0.9 %
Film thickness: applied in a wedge or at several thicknesses (for example 60, 90, 120 and 150 μm)

APPLICATION APPROACH:

PANELS ARE COATED AT INCREASING THICKNESS AND CURED UNDER STANDARD CONDITIONS.
The thickness at which pinholes or blisters first appear is recorded for each benzoin level.
Appearance, color and gloss are compared.
The results are used to define the safe working film thickness range.

ILLUSTRATIVE INITIAL COMPONENTS FOR THE 0.3 % BENZOIN TRIAL (% W/W)
Carboxyl polyester for HAA cure: 57.00 %
Hydroxyalkylamide (HAA) Resin: 3.00 %
Titanium dioxide: 30.00 %
Barium sulfate: 8.70 %
Flow agent: 1.00 %
Benzoin: 0.30 %
Total: 100.00 %
For the 0, 0.6 and 0.9 % benzoin trials, use respectively 9.00, 8.40 and 8.10 % barium sulfate, keep the other ingredients fixed. Each trial totals 100 %.

HYDROXYALKYLAMIDE (HAA) RESIN SIMILAR PRODUCTS AND ALTERNATIVES

HYDROXYALKYLAMIDE (HAA) RESIN AND TGIC
TGIC reacts with carboxyl polyesters through epoxy groups without releasing water, allowing thicker films and good edge coverage. However, its hazard classification has led many markets, especially Europe, to switch to HAA.

HYDROXYALKYLAMIDE (HAA) RESIN AND GLYCIDYL ESTER BLENDS
Mixtures of aromatic glycidyl esters (often called TGIC-free epoxy alternatives) cure without releasing water and can behave more like TGIC. They have their own hazard profiles and cost considerations.

HYDROXYALKYLAMIDE (HAA) RESIN AND HYDROXYPROPYL-TYPE HAA
Hydroxypropyl-type HAA grades react more slowly and can offer better degassing and lower overbake yellowing in some systems, often at a slightly different ratio.

HYDROXYALKYLAMIDE (HAA) RESIN AND BLOCKED ISOCYANATES
Hydroxyl-functional polyesters cured with blocked or uretdione isocyanates (polyurethane powders) give excellent appearance and thin films, but involve different resins and release blocking agents in some cases.

HYDROXYALKYLAMIDE (HAA) RESIN AND EPOXY-POLYESTER HYBRIDS
Hybrids are cheaper and excellent indoors but have poor exterior durability, they are not an outdoor alternative.

The best choice depends on durability requirements, oven type, film thickness, regulatory requirements and cost.

HOW DOES HYDROXYALKYLAMIDE (HAA) RESIN WORK AT THE MOLECULAR LEVEL?
 
Hydroxyalkylamide (HAA) Resin refers to β-hydroxyalkylamide crosslinkers and to binder systems in which these molecules cure carboxyl-functional polymers. A typical β-hydroxyalkylamide is a small, symmetrical molecule built on a diamide core, such as an adipamide, with two hydroxyalkyl arms on each amide nitrogen. Seen from the network side, each molecule acts as a multi-armed junction point: every arm can form one ester bond with a carboxyl group, so a single HAA molecule can tie several polymer chains together.
 
Molecular architecture: The four hydroxyalkyl arms radiate from two nitrogen atoms linked by a short aliphatic spacer. This compact, polyfunctional structure means relatively little hardener is needed by weight to crosslink a much larger amount of carboxyl-functional resin. The aliphatic backbone contains no aromatic rings or epoxide groups, which influences both the light stability of the cured network and the toxicological profile of the crosslinker.
 
Built-in activation: Each hydroxyl group sits on the carbon β to the amide nitrogen. On heating, the neighbouring amide participates in the reaction and forms a cyclic, oxazolinium-type intermediate that is much more susceptible to attack by carboxylic acids than a simple alcohol. This internal activation allows esterification at typical stoving temperatures without adding catalyst, and explains why hydroxyalkylamides are classed as reactive crosslinkers rather than ordinary polyols.
 
Partner polymers: The most common partners are carboxyl-terminated polyester resins in powder coatings, but the same chemistry works with carboxyl-functional acrylic resins and polyacids. In formaldehyde-free binders for glass and mineral fibres, for example, β-hydroxyalkylamides can crosslink polyacrylic acid or other polycarboxylic acids; the resulting polyester network binds the fibres together after curing.
 
Crosslink density and network design: The properties of the cured film are set by how many ester bridges form and how far apart they are. Resin acid value determines how many carboxyl groups are available; resin functionality and branching determine how many directions each chain can link in; and the hydroxyalkylamide content determines how many junction points exist. A higher crosslink density increases hardness, solvent and chemical resistance, while a lower density favours flexibility and impact strength. Formulators balance these factors by choosing the resin and adjusting the hardener level close to the stoichiometric ratio of hydroxyl to carboxyl groups.
 
Glass transition and storage stability: In powder coatings, the uncured resin–HAA mixture must stay solid and free-flowing during storage. This depends mainly on the glass transition temperature of the polyester; a sufficiently high value prevents the powder particles from softening and sticking together. After curing, the glass transition of the crosslinked network rises further because chain mobility is restricted by the new ester bonds.
 
Condensation and its consequences: Because each ester bond releases one water molecule, Hydroxyalkylamide (HAA) Resin systems cure by condensation. Water vapour must escape while the film is still fluid. If network formation is too rapid or the film too thick, trapped vapour can cause pinholes or blistering. Slower-reacting hydroxypropyl variants and controlled heating profiles give the vapour more time to leave the film.
 
Durability of the cured network: With saturated polyester or acrylic partners, the cured network consists mainly of aliphatic ester linkages and lacks strongly UV-absorbing groups. This supports good resistance to chalking and good gloss and colour retention outdoors, which is why HAA-cured systems are widely used in architectural and exterior powder coatings as an alternative to epoxy-based crosslinkers such as triglycidyl isocyanurate.
 
Moisture and hydrolysis: The hydroxyl and amide groups make the uncured crosslinker hydrophilic and able to absorb atmospheric moisture, so dry storage is important. In the cured film, ester bonds are generally stable but can be slowly hydrolysed under prolonged exposure to hot water, strong acids or alkalis, particularly if the network contains many unreacted polar end groups.
 
The final performance depends on the type and acid value of the partner resin, hardener ratio, film thickness, heating rate, stoving temperature and time, and the pigments and additives used. Hydroxyalkylamide (HAA) Resin dosage and process conditions should therefore be confirmed through laboratory trials.

QUALITY CONTROL AND PURCHASING CRITERIA FOR HYDROXYALKYLAMIDE (HAA) RESIN

RECOMMENDED INFORMATION TO REVIEW BEFORE PURCHASING:

EXACT CHEMICAL TYPE AND CAS NUMBER
Appearance and particle size
Melting range
Hydroxyl equivalent weight or hydroxyl value
Purity
Volatile and moisture content
Color
Recommended polyester:HAA ratio and cure schedule
Technical Data Sheet (TDS)
Safety Data Sheet (SDS)
Certificate of Analysis (COA)
Batch number and production date
Packaging (moisture-proof bags or drums) and net weight
Storage conditions and shelf life
REACH and regulatory information

Because Hydroxyalkylamide (HAA) Resin is used at low levels, small variations in hydroxyl equivalent or moisture can noticeably affect cure. Batch-to-batch consistency and moisture-proof packaging are therefore important purchasing criteria.

STORAGE AND HANDLING OF HYDROXYALKYLAMIDE (HAA) RESIN

The HAA curing agent should be stored in tightly closed, moisture-resistant original packaging in a cool, dry, well-ventilated place.
The product is hygroscopic, exposure to humid air can cause caking and may influence reactivity and degassing. Opened packages should be resealed immediately.
Storage near heat sources should be avoided. The product should be kept away from strong oxidizing agents, strong acids and strong bases.
Dust formation should be minimized during weighing and premixing, and equipment handling fine powder should be grounded to reduce static and dust explosion risks.
Transport: For the transport classification of the supplied Hydroxyalkylamide (HAA) Resin grade, please contact Ataman Kimya.
Spilled powder should be collected by sweeping or vacuuming with minimal dust generation and placed in suitable containers.

SAFETY INFORMATION OF HYDROXYALKYLAMIDE (HAA) RESIN

Hazard classification: Supplier safety data sheets for tetrakis(2-hydroxyethyl)adipamide use the signal word "Warning". Depending on the supplier, hazard statements include causes skin irritation, causes serious eye irritation, may cause respiratory irritation or harmful if swallowed.
Eyes: Rinse cautiously with water for several minutes, remove contact lenses if easy to do, seek medical advice if irritation persists.
Skin: Wash with soap and water, remove contaminated clothing.
Inhalation: Move to fresh air, seek medical advice if symptoms persist.
Ingestion: Rinse mouth, do not induce vomiting, seek medical advice.
Fire: Combustible powder, fine dust may form explosive mixtures in air. Use water spray, foam, dry chemical or carbon dioxide. Combustion can produce carbon oxides and nitrogen oxides.
Personal protection: Gloves, safety goggles, dust mask or respirator where dust is generated, and protective clothing.
Environment: Avoid release into drains and water.
Waste: Dispose of according to local regulations.

WHAT SHOULD BE CONSIDERED WHEN BUYING HYDROXYALKYLAMIDE (HAA) RESIN?

BEFORE PURCHASING, THE FOLLOWING INFORMATION SHOULD BE CLARIFIED:

HAA TYPE REQUIRED (HYDROXYETHYL OR HYDROXYPROPYL TYPE)
Polyester system and its acid value
Required cure schedule and oven type
Required physical form (standard powder, micronized, masterbatch)
Specification limits (melting range, hydroxyl equivalent, moisture)
Quantity and packaging
Required documents (TDS, SDS, COA, REACH)
Current crosslinker specification if replacing TGIC or another HAA

The price of Hydroxyalkylamide (HAA) Resin depends on the cost of diethanolamine and adipic acid derivatives, energy, purity and form, order volume, packaging and logistics.

SUPPLY OF HYDROXYALKYLAMIDE (HAA) RESIN FROM ATAMAN KIMYA

The HAA crosslinker is the main TGIC-free crosslinker for outdoor polyester powder coatings. Powder coating producers planning to purchase it should define their polyester system, cure conditions and specification requirements.
Ataman Kimya can provide information on available HAA grades, specifications, packaging and price quotations.
Current stock, origin and specification details should be confirmed with Ataman Kimya before ordering.

INFORMATION THAT HELPS PREPARE A QUOTATION:

POWDER COATING TYPE AND END USE
Polyester system and acid value
Required HAA type and form
Estimated quantity
Packaging preference
Required documents

FREQUENTLY ASKED QUESTIONS ABOUT HYDROXYALKYLAMIDE (HAA) RESIN

WHAT IS HYDROXYALKYLAMIDE (HAA) RESIN?
The beta-hydroxyalkylamide hardener is a β-hydroxyalkylamide crosslinker, most commonly N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide, used to cure carboxyl polyester powder coatings.

IS HAA REALLY A RESIN?
In the trade it is often called a resin, but technically it is a low-molecular-weight crosslinker (hardener) that cures polyester resins.

WHAT IS THE CAS NUMBER OF HYDROXYALKYLAMIDE (HAA) RESIN?
The CAS number of the most common HAA, tetrakis(2-hydroxyethyl)adipamide, is 6334-25-4.

WHAT IS THE EC NUMBER OF HYDROXYALKYLAMIDE (HAA) RESIN?
The EC number of tetrakis(2-hydroxyethyl)adipamide is 405-370-0.

WHAT IS THE CHEMICAL FORMULA OF HYDROXYALKYLAMIDE (HAA) RESIN?
C14H28N2O6, molecular weight 320.38 g/mol.

HOW DOES HAA CURE POLYESTER POWDER COATINGS?
Its β-hydroxyl groups esterify the carboxyl groups of the polyester during baking, forming a crosslinked network and releasing water.

WHAT IS THE TYPICAL POLYESTER TO HAA RATIO?
Typically about 95:5 to 96.5:3.5 by weight, depending on the polyester acid value and supplier recommendations.

WHAT CURE SCHEDULE IS USED FOR HAA POWDERS?
Standard systems are typically cured for about 10 minutes at 160–180 °C object temperature, exact schedules depend on the polyester.

WHY IS HAA USED INSTEAD OF TGIC?
TGIC carries a severe hazard classification in the EU. HAA provides a TGIC-free route to durable outdoor polyester powders.

WHAT ARE THE LIMITATIONS OF HAA?
Water released during curing can cause pinholes in thick films, and some systems show yellowing on overbake in gas-fired ovens.

IS HYDROXYALKYLAMIDE (HAA) RESIN SOLUBLE IN WATER?
It is a polar, hydroxyl-rich compound and is soluble in water, which is one reason it must be protected from humidity.

IS HYDROXYALKYLAMIDE (HAA) RESIN HAZARDOUS?
Supplier safety data sheets classify it with "Warning", with irritation or acute oral toxicity hazards depending on the supplier.

WHAT IS THE UN NUMBER OF HYDROXYALKYLAMIDE (HAA) RESIN?
For the transport classification of the supplied grade, please contact Ataman Kimya.

IS HAA USED IN COSMETICS OR FOOD?
No. It is an industrial coating crosslinker.

HOW SHOULD HYDROXYALKYLAMIDE (HAA) RESIN BE STORED?
In closed, moisture-proof packaging in a cool, dry place, away from heat and incompatible materials.

WHAT ALTERNATIVES EXIST TO HAA?
TGIC, glycidyl ester blends, hydroxypropyl-type HAA and polyurethane powder systems, depending on requirements.

WHICH SPECIFICATIONS ARE IMPORTANT WHEN BUYING HAA?
Chemical type, melting range, hydroxyl equivalent weight, moisture, particle size and color.

HYDROXYALKYLAMIDE (HAA) RESIN – TECHNICAL SUMMARY

The HAA curing agent is the trade name of β-hydroxyalkylamide crosslinkers for powder coatings. The main type is N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide (CAS 6334-25-4, EC 405-370-0, C14H28N2O6, 320.38 g/mol), a white powder with a melting range of about 115–130 °C and a hydroxyl equivalent weight of about 80–90 g/eq.
Its four β-hydroxyl groups esterify carboxyl-functional polyesters during baking, without catalyst, forming durable networks and releasing water.
The HAA crosslinker is the leading TGIC-free curing agent for outdoor polyester powder coatings used on architectural aluminum, outdoor furniture, machinery and general industrial parts.
Typical polyester:HAA ratios are about 95:5, with cure schedules around 10 minutes at 160–180 °C. Degassing and film thickness must be controlled to avoid pinholes.
It is classified with "Warning" in supplier safety data sheets and should be handled with dust control and protective equipment.
Companies planning to source Hydroxyalkylamide (HAA) Resin through Ataman Kimya are advised to share their polyester system, cure conditions, required grade, quantity and documentation needs.

Hydroxyalkylamide (HAA) Resin can be sourced from ATAMAN KİMYA. For further information and supply inquiries about Hydroxyalkylamide (HAA) Resin, please contact ATAMAN KİMYA.