ARADUR 35-1

ARADUR 35-1 is a waterborne polyamine-adduct epoxy curing agent developed for two-component aqueous epoxy systems requiring strong adhesion, anti-corrosion performance, high gloss and good flow. The commercial grade is supplied as an approximately 51-55% solids aqueous solution and is designed primarily for waterborne primers and related industrial coating systems on mineral and metallic substrates. ARADUR 35-1 combines reactive amine functionality with water compatibility, allowing epoxy formulations to reduce or avoid conventional volatile organic solvent while maintaining practical application properties and durable cured-film performance.

PRODUCT IDENTITY

Product name: ARADUR 35-1
Product type: Waterborne epoxy curing agent / hardener
Chemical family: Polyamine adduct
Broader chemical family: Polyamines / amine adducts
Carrier: Water
Physical form: Liquid
Appearance: Clear to slightly turbid liquid
Color: Gardner ≤6
Odor: Slight
Solids content: Approximately 51-55%
Viscosity at 25°C: Approximately 19-35 Pa·s / 19,000-35,000 mPa·s
Amine value: Approximately 100-120 mg KOH/g
Active hydrogen equivalent weight: Approximately 380 g/eq
Density at 20°C: Approximately 1.08 g/cm³
Flash point: Greater than approximately 100°C
Typical pot life with ARALDITE GY 776 in selector literature: Approximately 90 minutes
Recommended mix ratio with ARALDITE GY 776: Approximately 100:200 parts by weight
Recommended mix ratio with ARALDITE PZ 33757/67: Approximately 100:144 parts by weight
Mix-ratio adjustment: Deviations of approximately ±10% are historically described as tolerable in the referenced systems
Primary functions: Curing agent, hardener and crosslinker
Primary end use: Primers
Material compatibility: Mineral substrates
Key current product features: Anti-corrosion protection, excellent adhesion, high gloss and improved flow
Benzyl alcohol: Published selector information identifies the grade as benzyl-alcohol-free
Storage range: Approximately 2-40°C in sealed original packaging
CAS Number: Commercial waterborne polyamine-adduct mixture; no single CAS number should be assigned to the complete trade grade without the current SDS
EC Number: Commercial mixture; no single EC number should be assigned to the complete trade grade without the current SDS
Molecular Formula: Not applicable to the commercial formulated mixture
Molecular Weight: Variable / not applicable as one fixed value
ARADUR 35-1 should be treated as a commercial aqueous polyamine-adduct curing-agent mixture rather than as one pure molecular substance. The active hardener contains a distribution of amine-containing structures, while water forms a substantial part of the supplied product. Assigning one molecular formula or molecular weight to the entire grade would therefore be technically misleading. Product-specific SDS information should be used whenever formal component identities, CAS numbers, concentration ranges or hazard classifications are required.

WHAT IS ARADUR 35-1?

ARADUR 35-1 is a reactive waterborne hardener intended to crosslink epoxy resins through epoxy-amine chemistry while remaining compatible with aqueous coating technology. The product allows the curing-agent side of a two-component epoxy system to be handled as a water-containing material rather than as a conventional solvent-cut amine. This supports waterborne coating design and can help reduce solvent emissions.
The active polyamine adduct contains amine hydrogens that react with oxirane groups in epoxy resin. When the resin and hardener are mixed, molecular weight rises progressively until a crosslinked thermoset network forms. Water remains a physical carrier rather than becoming part of the epoxy network and must leave the film during drying and cure.

Waterborne epoxy systems require a careful balance between chemical reaction and physical film formation. The components must remain sufficiently compatible during mixing and application, water must evaporate, resin particles or emulsified phases must coalesce, and epoxy-amine reaction must proceed to an adequate degree of conversion. ARADUR 35-1 is designed to support this combined process.

POLYAMINE ADDUCT CHEMISTRY

A polyamine adduct is produced by partially reacting a polyamine with another functional material, commonly an epoxy-containing compound, before the curing agent is sold. This pre-reaction modifies free-amine content, molecular weight, viscosity, compatibility and cure behavior compared with the original unmodified amine.
Adduction can reduce the volatility and aggressiveness associated with low-molecular-weight amines while improving compatibility with epoxy resin. The resulting hardener still contains reactive amine hydrogens capable of opening epoxy rings during final cure.
In ARADUR 35-1, the active adduct is dispersed or dissolved in water to create a waterborne curing-agent form. The exact proprietary molecular composition should not be reconstructed from generic polyamine chemistry. Performance data, AHEW, amine value and manufacturer guidance are more useful for formulation than trying to assign a single molecular structure.

HOW EPOXY CURING WORKS

Epoxy resins contain strained three-membered oxirane rings. Primary and secondary amine hydrogens in ARADUR 35-1 attack these rings and open them, forming carbon-nitrogen bonds and hydroxyl groups. Repeated reactions connect resin and curing-agent molecules into a three-dimensional network.
As crosslinking proceeds, the coating moves from a mixed liquid toward a tack-free film and eventually a chemically resistant thermoset. The degree of cure continues to increase after the film appears dry. 

Hardness, solvent resistance and water resistance can therefore continue developing for hours or days depending on temperature and formulation.
Water does not participate directly in the principal crosslinking reaction. Instead, it controls application viscosity and supports waterborne processing. It must leave the wet film at an appropriate rate so that coalescence and reaction are not disrupted.

WATERBORNE EPOXY TECHNOLOGY

Waterborne epoxy coatings typically use one of several resin forms, including liquid epoxy resin emulsions, self-dispersing epoxy resins or pre-dispersed solid epoxy resin systems. ARADUR 35-1 can be matched with suitable water-compatible resin technology so that both components can be combined without immediate phase separation.
The water phase lowers VOC and allows tools and application equipment to be cleaned more easily before cure, depending on the complete formulation. Water also changes drying behavior compared with solvent-borne epoxy. Relative humidity, airflow and substrate temperature become particularly important because evaporation slows as ambient humidity rises.

A successful waterborne epoxy must balance pot life, emulsion stability, film coalescence and chemical cure. If the water leaves too slowly, the film can remain soft or sensitive. If the formulation loses colloidal stability, separation, seeding or loss of gloss can occur.

SOLIDS CONTENT

ARADUR 35-1 contains approximately 51-55% solids. This means roughly half of the supplied product consists of active non-volatile curing-agent material and the balance is mainly water.
Solids content is critical to mix-ratio interpretation. A waterborne hardener cannot be compared directly by wet weight with a 100% solids hardener because part of the supplied mass is carrier. The manufacturer-published AHEW and recommended formulation ratios should therefore be used for the product as supplied.

If solids content changes materially, a fixed wet-weight addition delivers a different amount of active curing chemistry. Solids determination is therefore an important quality-control parameter for this type of product.

VISCOSITY

ARADUR 35-1 has a relatively high supplied viscosity of approximately 19-35 Pa·s at 25°C. This corresponds to approximately 19,000-35,000 mPa·s.
The high viscosity is characteristic of a concentrated waterborne polymeric amine adduct rather than a simple low-molecular-weight amine solution. Temperature has a strong effect, so the material should be conditioned to the specified test temperature before viscosity is evaluated.
High supplied viscosity does not prevent use in waterborne coatings because the product can be diluted with water under controlled conditions and blended with the resin system during formulation. Mixing equipment must nevertheless provide enough shear for uniform distribution.

AMINE VALUE

The specified amine value is approximately 100-120 mg KOH/g. This analytical value reflects total basic amine functionality in the commercial material.
Amine value is useful for batch quality control and identification, but it should not be treated as interchangeable with active hydrogen equivalent weight. Some basic nitrogen sites can contribute to titration behavior without supplying the same number of reactive hydrogens.
For stoichiometric epoxy formulation, AHEW and manufacturer-recommended mix ratios are more directly useful. Amine value remains valuable as a consistency parameter.

ACTIVE HYDROGEN EQUIVALENT WEIGHT

ARADUR 35-1 has a typical active-hydrogen equivalent weight of approximately 380 g/eq as supplied. AHEW expresses how much curing agent provides one equivalent of reactive amine hydrogen.
The relatively high value reflects both the molecular architecture of the adduct and the presence of water in the supplied product. It should therefore not be compared directly with an anhydrous low-molecular-weight amine without considering the formulation form.
The correct hardener level depends on the epoxy equivalent weight and physical form of the chosen resin. 

MIX RATIO WITH ARALDITE GY 776

Technical data recommend ARALDITE GY 776 and ARADUR 35-1 at approximately 100:200 parts by weight. This is a product-specific ratio and should not be interpreted as a universal two-to-one rule for every epoxy resin.
The high hardener weight is consistent with the aqueous, partially active nature of ARADUR 35-1 and its relatively high AHEW. The commercial resin and curing agent must be considered in their supplied forms.
Selector literature associates this combination with a pot life of approximately 90 minutes under the referenced conditions. Actual practical working time depends on temperature, pigment loading, water dilution, batch size and application method.

MIX RATIO WITH ARALDITE PZ 33757/67

Technical information recommends ARALDITE PZ 33757/67 and ARADUR 35-1 at approximately 100:144 parts by weight. This different ratio illustrates why mix ratio must always be tied to the exact resin grade.
The published guidance allows deviations of approximately ±10% in the referenced system. A higher proportion of hardener tends to improve flexibility and adhesion, while a lower proportion can improve anti-corrosion protection.
This adjustment range should be treated as formulation guidance for the specified system rather than a general rule for all resin-hardener combinations.

POT LIFE

Published selector data associate ARADUR 35-1 with a pot life of roughly 90 minutes when used with the referenced ARALDITE GY 776 system. More recent coating-selector literature lists a gel-time value around 70 minutes under its own standardized protocol.
Pot life and gel time are not necessarily identical tests. Pot life refers to the period during which the mixed coating remains usable, while gel time identifies when the reactive system reaches a defined gel state. The actual application window may end earlier if viscosity, flow or gloss development becomes unacceptable.

Waterborne systems can also show less obvious pot-life behavior than conventional solvent-borne epoxies. A mixture can remain visually fluid while chemical advancement has already progressed enough to reduce final coating performance. Formulators should therefore validate end-of-pot-life behavior using application tests rather than relying only on cup viscosity.

FAST CURE BEHAVIOR

It is currently identified ARADUR 35-1 as a very fast hardener option in ARALDITE PZ 3961-1 waterborne epoxy-dispersion systems. This may appear inconsistent with older selector pot-life values, but the difference reflects the strong influence of resin type, dispersion structure and formulation on cure rate.
A hardener can produce a moderate working time in one liquid-resin system and significantly faster film development in another waterborne dispersion. Cure descriptors should therefore always be linked to the complete resin-hardener combination.
Fast film cure can be beneficial for primers and concrete coatings where early hardness, early water resistance or faster recoating is required. Excessive acceleration can reduce flow or working time, so the system must be balanced for the intended application.

DENSITY

The typical density of ARADUR 35-1 is approximately 1.08 g/cm³ at 20°C. Density supports mass-to-volume conversion and can be used as an incoming quality-control check.
Mix ratios are normally more reliable on a weight basis because waterborne resin and hardener densities differ and can vary with temperature. Volumetric dispensing should only be used after the ratio has been calculated from accurate component densities.
A large unexpected density shift can indicate concentration change or contamination, although amine value, solids and viscosity provide more direct chemical information.

FLASH POINT

The typical flash point is greater than approximately 100°C. This relatively high value is consistent with a waterborne product and distinguishes ARADUR 35-1 from curing agents diluted heavily with flammable organic solvent.
A high flash point does not mean that fire precautions can be ignored. The organic portion can burn under sufficient heat, and decomposition can generate carbon monoxide, carbon dioxide, nitrogen oxides and other toxic gases and vapors.
Fire handling and storage requirements should follow the current SDS rather than generic assumptions based solely on water content.

VOC-FREE CHARACTER

Current product information identifies ARADUR 35-1 as VOC-free. This is an important advantage for formulators targeting lower-emission epoxy coatings.
The VOC-free claim applies to the curing-agent grade as currently positioned. The complete mixed coating may still contain VOC from the epoxy-resin component, coalescing aids, wetting solvents, defoamers or other additives.
Finished-product VOC must therefore be calculated or measured according to the applicable regional regulation. A VOC-free hardener supports low-VOC design but does not automatically make the final coating VOC-free.

BENZYL-ALCOHOL-FREE CHARACTER

Published selector information identifies ARADUR 35-1 as benzyl-alcohol-free. Benzyl alcohol is commonly used in some amine curing agents as a viscosity modifier, accelerator or formulation aid.
A benzyl-alcohol-free waterborne hardener can be useful where the formulator wishes to avoid this component for regulatory or performance reasons. The absence of benzyl alcohol does not mean the product consists only of active amine because water remains the principal carrier.
Product-specific SDS and compliance declarations should be used when a formal restricted-substance claim is required.

DILUTION WITH WATER

ARADUR 35-1 can be further diluted with water, but historical technical information notes that additional dilution can produce slight colloidal turbidity. This turbidity generally does not indicate immediate precipitation.
At temperatures above approximately 40°C, highly diluted mixtures may become less stable and precipitation risk can increase. Dilution and storage temperature therefore need to be controlled.
Water should be added gradually under good agitation. Localized over-dilution can create temporary concentration gradients and destabilize the adduct. Deionized water is generally preferred in sensitive industrial formulations because dissolved salts can influence colloidal stability.

COLLOIDAL STABILITY

Waterborne curing agents are not simply molecular solutions in the same way as low-molecular-weight salts. Their polymeric structures can form colloidal or associated domains in water.
Changes in concentration, ionic strength and temperature can alter these structures and change appearance from clear to slightly turbid. A small appearance change during validated dilution does not necessarily mean loss of performance.
Severe phase separation, sedimentation or irreversible precipitation should nevertheless be investigated because non-uniform curing-agent distribution can produce inconsistent cure.

APPLICATIONS

Waterborne anti-corrosion primers

Anti-corrosion primers are a primary application area for ARADUR 35-1. The product contributes strong adhesion and allows development of low-VOC epoxy primer technology. Corrosion protection comes from the complete coating system, including resin, hardener, pigment package, surface preparation and dry-film thickness.

Metal primers

ARADUR 35-1 can be used in waterborne primers for prepared steel and other suitable metal substrates. Strong adhesion and good flow help create a continuous barrier film. Metal-specific pretreatment and corrosion-control pigment selection remain important.

Mineral-substrate primers

Current product information specifically lists compatibility with mineral substrates. ARADUR 35-1 is therefore relevant to primers used on concrete, masonry and related surfaces. Surface porosity and moisture condition should be evaluated before application.

Concrete primers

Waterborne epoxy primers can penetrate and consolidate suitably prepared concrete surfaces while providing a chemically resistant base for subsequent layers. ARADUR 35-1 can be used where low VOC, good adhesion and relatively fast cure are required.

Industrial maintenance coatings

Waterborne industrial maintenance systems can use ARADUR 35-1 to reduce solvent emissions while retaining epoxy durability. Typical targets include equipment, steel structures and indoor industrial environments. Exterior systems may require a UV-resistant topcoat.

Direct-to-metal coatings

A properly formulated waterborne epoxy based on ARADUR 35-1 can be evaluated for direct-to-metal applications. DTM performance depends strongly on corrosion-inhibitive pigment selection, edge coverage, substrate cleanliness and film thickness.

High-gloss waterborne epoxy coatings

High gloss is one of the features highlighted in current information. Good film coalescence and flow are necessary because microscopic roughness reduces gloss. Resin dispersion, pigment volume concentration and drying conditions must therefore be optimized together.

Waterborne topcoats

Although current end-use listing emphasizes primers, ARADUR 35-1 chemistry can be considered in compatible waterborne topcoat formulations where the required appearance and durability are achieved. UV exposure should be considered because conventional epoxy topcoats can chalk outdoors.

Floor primers

Concrete flooring systems often begin with a primer that wets the mineral surface and supports adhesion of later layers. ARADUR 35-1 can be useful in waterborne epoxy floor-primer technology where low VOC and good adhesion are important.

Floor coatings

The hardener can also be evaluated in waterborne epoxy floor coatings. Final performance depends on film build, resin selection and cure conditions. Waterborne floor systems require adequate drying before exposure to washing or traffic.

Factory and warehouse coatings

Industrial floors, walls and structural components in factories and warehouses can benefit from waterborne epoxy systems where odor and solvent emissions must be reduced. ARADUR 35-1 provides a route to reactive two-component technology in these environments.

Machinery primers

Equipment and machinery can use waterborne epoxy primers to provide adhesion and corrosion protection under subsequent topcoats. ARADUR 35-1 can contribute to such systems when production drying conditions are suitable.

General industrial metal coatings

Steel cabinets, fabricated components, shelving, structural parts and industrial hardware can use waterborne epoxy primer systems. Flow and gloss advantages can improve appearance while the epoxy network provides mechanical durability.

Warm-curing industrial coatings

technical information for ARALDITE PZ 3961-1 identifies warm-curing industrial coatings around 60-80°C as an application area and lists ARADUR 35-1 among compatible hardeners. Moderate heat can accelerate water removal and epoxy cure.

Fast-curing concrete coatings

ARALDITE PZ 3961-1 literature identifies ARADUR 35-1 as a very fast hardener option in fast-curing concrete coating formulations. This can support faster return to service when substrate and environmental conditions are controlled.

Primer-sealers

Low- to medium-build waterborne epoxy primer-sealers can reduce surface absorbency and provide a chemically bonded base for subsequent coats. ARADUR 35-1 can be used in suitable mineral-substrate systems.

Barrier coatings

Waterborne epoxy barrier layers can reduce moisture and chemical penetration when fully cured. ARADUR 35-1 contributes to network formation, while barrier performance depends on film continuity and filler selection.

Infrastructure coatings

Selected infrastructure environments can use waterborne epoxy primers where VOC restrictions and worker exposure considerations favor aqueous technology. Bridges, plants and utility structures may still require system-specific qualification.

Interior protective coatings

Indoor industrial areas can benefit from reduced solvent odor and emissions. ARADUR 35-1 supports two-component waterborne epoxy coatings where adhesion, hardness and cleaning resistance are needed.

Waterborne epoxy adhesives

Although the current end-use emphasis is coatings and primers, polyamine-adduct chemistry can also be evaluated in specialized waterborne epoxy adhesive formulations where compatible resin dispersions are used. Bond-line water removal must be considered carefully.

Cementitious hybrid systems

Waterborne epoxy chemistry can sometimes be combined with mineral or cementitious components to improve adhesion and toughness. ARADUR 35-1 can be evaluated where the alkaline mineral environment and water balance are compatible. Such use requires application-specific validation.

Pigmented primers

ARADUR 35-1 can cure pigmented waterborne epoxy primers containing titanium dioxide, iron oxides, extenders and anti-corrosive pigments. Pigment surfaces and dispersants influence both colloidal stability and cure.

Clear sealers

In selected systems, low-pigment or clear waterborne epoxy sealers can be formulated for mineral substrates. Film clarity depends on resin dispersion, cure and moisture. ARADUR 35-1's own Gardner color should be considered in very pale applications.

ARALDITE GY 776 SYSTEM

ARALDITE GY 776 is one of the epoxy resins historically used to characterize ARADUR 35-1. It is recommended a 100:200 parts-by-weight resin-to-hardener ratio for the referenced system.
Selector literature gives a pot life around 90 minutes with this combination. The value is useful for comparison but should not be treated as a guaranteed field pot life because pigments, temperature and dilution alter reaction kinetics.
The large hardener addition reflects the water content and active-hydrogen equivalent of ARADUR 35-1. Formulators should use the product as supplied when following the published ratio.

ARALDITE PZ 33757/67 SYSTEM

Technical data recommend ARALDITE PZ 33757/67 and ARADUR 35-1 at approximately 100:144 parts by weight. This waterborne resin-hardener combination provides a different stoichiometric balance from the GY 776 system.
The same literature describes approximately ±10% flexibility around the recommended hardener level. More ARADUR 35-1 improves flexibility and adhesion, while less can improve anti-corrosion protection.
This relationship is formulation-specific. Excess hardener beyond the validated range can leave unreacted amine and increase water sensitivity, while insufficient hardener can reduce conversion.

ARALDITE PZ 3961-1 COMPATIBILITY

Current information for ARALDITE PZ 3961-1 lists ARADUR 35-1 as one of the hardeners used with this waterborne epoxy dispersion. ARADUR 35-1 is specifically described there as very fast relative to the other compatible curing agents.
The resin literature also identifies fast-curing concrete coatings and warm-curing industrial coatings as application areas. Addition of compatible liquid-resin emulsion can improve film coalescence and concrete wetting in certain systems.
The exact ARADUR 35-1 level should follow the resin-specific technical documentation rather than being copied from GY 776 or PZ 33757/67.

FILM COALESCENCE

Waterborne epoxy coatings depend on both chemical cure and physical coalescence. Resin particles or dispersed domains must come together to form a continuous film as water evaporates.
If coalescence is incomplete, the coating can remain porous, weak or hazy even if some epoxy-amine reaction occurs. Temperature below the effective film-forming range can therefore reduce performance.
Coalescing aids or compatible liquid epoxy resin emulsions can improve film formation in difficult conditions. Their effect on VOC and cure must be included in formulation design.

FLOW

Improved flow is one of the features highlighted for ARADUR 35-1. Flow allows the wet coating to redistribute after application and reduce brush, roller or spray texture.
Waterborne epoxy flow depends on viscosity profile, surface tension, water evaporation and coalescence. Excessive thickening can reduce leveling, while insufficient structure can cause sag.
Flow additives can be used where required, but they should be tested for compatibility with the amine hardener and epoxy dispersion.

HIGH GLOSS

High gloss is another published product feature. Gloss requires a smooth and uniform final surface.
Waterborne systems can lose gloss if drying is too fast, coalescence is incomplete, pigment dispersion is poor or surface foam remains. ARADUR 35-1 can support high-gloss systems, but gloss ultimately depends on the complete formulation and application conditions.
Low pigment volume and appropriate resin selection are generally important for maximum gloss.

ANTI-CORROSION PERFORMANCE

Current information highlights anti-corrosion protection as a key feature of ARADUR 35-1. The cured epoxy network creates a barrier to water, oxygen and ions, while strong adhesion helps prevent lateral underfilm corrosion.
Pigment selection can enhance protection. Zinc phosphate, lamellar fillers and other anti-corrosive materials may be used depending on regulatory and performance requirements.
Lower hardener level within the historically validated adjustment range can improve anti-corrosion protection in the cited system, illustrating the importance of crosslink balance.

ADHESION

Excellent adhesion is one of the primary published advantages of ARADUR 35-1. Adhesion depends on wetting, chemical interaction and mechanical interlocking with the substrate.
Mineral surfaces should be clean and mechanically sound. Concrete laitance, dust and curing compounds reduce bonding. Steel should be cleaned of oil, soluble salts and corrosion products.
Waterborne application can improve working conditions, but residual surface moisture must still be controlled according to the specific coating design.

FLEXIBILITY

Higher hardener content within the published ±10% adjustment range is associated with greater flexibility and better adhesion in the referenced formulation. This is consistent with changes in network stoichiometry and polymer segment distribution.
Flexibility helps coatings tolerate substrate movement and thermal cycling. Excess flexibility can reduce hardness and chemical resistance, so the formulation should be balanced to end-use demands.
Film flexibility should be evaluated after full cure rather than during early drying.

WATER EVAPORATION

Water evaporation is a critical part of film formation. Low airflow and high humidity slow drying, while warm dry air accelerates it.
If the film surface closes before deeper water escapes, residual moisture can become trapped and delay cure. Thick films are more sensitive than thin primers.
Application specifications should therefore define temperature, relative humidity and maximum wet-film thickness.

HUMIDITY EFFECTS

High humidity reduces the driving force for water evaporation and can extend dry time. It can also increase the risk of surface defects or poor early water resistance.
Very low humidity can cause rapid surface drying, which may interfere with leveling or coalescence in some formulations.
Environmental control is therefore as important in waterborne epoxy as in solvent-borne systems, even though the evaporation mechanism differs.

LOW-TEMPERATURE APPLICATION

Low temperature increases viscosity, slows epoxy reaction and slows water evaporation. This combination can make waterborne systems difficult to cure properly.
Formulations intended for cooler conditions may require a faster resin-hardener combination or controlled heating. Substrate temperature should remain high enough to avoid condensation.
ARADUR 35-1 can provide fast cure in selected waterborne dispersion systems, but practical minimum application temperature must be established for the finished coating.

WARM CURING

Moderate heat can accelerate both water removal and chemical cure. It is identified warm-curing industrial coatings around 60-80°C as relevant to ARALDITE PZ 3961-1 systems using compatible ARADUR hardeners including ARADUR 35-1.
Warm curing can increase throughput and shorten time to final properties. The coating should be heated in a controlled manner so that water can escape without blistering.
Substrate mass determines how quickly the film actually reaches the target temperature.

DILUTION STRATEGY

Water can be used to adjust application viscosity, but excessive dilution reduces wet-film solids and can increase sag, shrinkage and drying time.
Historical product data note that further dilution of ARADUR 35-1 can create slight colloidal turbidity. This appearance change can be acceptable if no precipitation occurs and performance remains stable.
Dilution should be validated at the intended storage and application temperature. Highly diluted mixtures should not be exposed unnecessarily to temperatures above approximately 40°C.

ORDER OF ADDITION

Waterborne epoxy systems can be sensitive to addition sequence. The resin dispersion, pigments, water, additives and hardener should be introduced in an order that preserves colloidal stability.
The exact sequence depends on whether pigments are dispersed into the resin side or into a separate grind. ARADUR 35-1 should generally be incorporated under adequate agitation to avoid localized concentration differences.
A formulation procedure should be standardized because changing order of addition can change viscosity, foam and pot life.

PIGMENT DISPERSION

Pigment dispersion in waterborne epoxy primers requires dispersants compatible with both the aqueous phase and reactive amine chemistry.
Pigments with high surface area can adsorb surfactants and modify viscosity. Anti-corrosive pigments can also influence pH and ionic strength.
The pigment grind should remain stable after the ARADUR 35-1 component is introduced. Seeding or flocculation indicates incompatibility.

ANTI-CORROSIVE PIGMENTS

Zinc phosphate and related non-lead corrosion-inhibitive pigments can be used in waterborne epoxy primers. Their efficiency depends on pigment chemistry, loading and the barrier properties of the binder.
The hardener does not replace the pigment's inhibitive function. ARADUR 35-1 provides the crosslinked matrix that supports adhesion and barrier protection.
Pigment choice must also consider waterborne dispersion stability.

MINERAL FILLERS

Calcium carbonate, barytes, talc, mica and other extenders can adjust cost, rheology, sanding and barrier properties.
Mineral fillers introduce ionic surfaces that can affect a waterborne formulation more strongly than they affect a simple solvent-borne epoxy. Surface treatment and dispersant selection therefore matter.
High filler loading can reduce film continuity if pigment volume concentration becomes excessive.

RHEOLOGY MODIFIERS

Waterborne epoxy primers can use associative thickeners, cellulose derivatives, clays or other rheology-control technologies depending on the formulation.
The rheology modifier must remain compatible after the amine hardener is added. pH and electrolyte changes can alter thickening efficiency.
Sag, flow and spray properties should be evaluated over the entire pot-life window because viscosity can change as cure progresses.

DEFOAMERS

Mixing waterborne epoxy components can generate foam. Entrapped air causes pinholes, weak spots and gloss loss.
Suitable defoamers can improve air release, but excessive defoamer can create craters or reduce intercoat adhesion. The defoamer should be selected specifically for two-component waterborne epoxy.
Foam should be evaluated immediately after mixing and after application.

SURFACTANTS AND WETTING AGENTS

Wetting agents help waterborne coatings spread over pigments and substrates, but their concentration must be controlled.
Excess surfactant can increase water sensitivity and reduce early resistance. It can also influence foam and intercoat adhesion.
The curing-agent system already contains water-compatible functionality, so the overall surfactant package should be optimized rather than maximized.
pH
Polyamine curing agents are basic, so adding ARADUR 35-1 can change formulation pH.
pH influences dispersion stability, corrosion behavior, rheology and additive performance. A waterborne coating should therefore be evaluated after full component mixing rather than only on the resin side.
Strong acid adjustment can neutralize amine functionality and reduce cure, so pH modification must be performed carefully.

EARLY WATER RESISTANCE

Waterborne epoxy films can remain sensitive to water during early cure because both carrier water and incomplete crosslinking are present.
Early exposure can cause whitening, softening or loss of gloss. Resistance improves as water leaves and the network develops.
Fast-reacting ARADUR 35-1 systems can improve early property development, but full cure remains necessary before severe service.

CHEMICAL RESISTANCE

Fully cured epoxy systems can resist water, oils and many industrial chemicals. The exact resistance profile depends on resin type, cure level and formulation.
Waterborne technology does not inherently mean weaker final chemical resistance. Once the water has evaporated and the network is fully cured, the remaining thermoset can provide strong performance.
Chemical immersion should be tested only after the validated full-cure period.

ABRASION AND MECHANICAL DURABILITY

Epoxy coatings provide good mechanical durability when properly cured. ARADUR 35-1 contributes to network formation, while abrasion resistance also depends on resin, fillers and film thickness.
Floor coatings may require additional hard mineral filler or specialized resin technology for heavy traffic.
Early abrasion testing can underestimate final performance because waterborne epoxy continues curing after apparent dry.

RECOATABILITY

Waterborne epoxy primers can be recoated with compatible waterborne or solvent-borne systems when the surface is clean and within the appropriate recoat window.
If the primer is fully cured, light abrasion may be required to improve mechanical adhesion. Contamination from dust, oils or amine-derived surface deposits should be removed.
The exact recoat interval depends on temperature, humidity and the topcoat chemistry.

UV WEATHERING

Conventional epoxy binders can chalk and lose gloss under prolonged sunlight. ARADUR 35-1 should not be presented as a UV stabilizer.
For exterior decorative systems, the waterborne epoxy can serve as primer or intermediate coat beneath a weather-resistant polyurethane, acrylic or polysiloxane topcoat.
The primer can retain corrosion-protection value even when an unprotected epoxy surface loses cosmetic gloss.

QUALITY CONTROL

Important ARADUR 35-1 quality parameters include appearance, Gardner color, amine value, solids content and viscosity. These are published as controlled or typical properties depending on the parameter.
Appearance should remain clear to slightly turbid without abnormal separation. Solids confirm concentration, viscosity controls handling consistency and amine value monitors reactive chemistry.
Functional testing with a standardized epoxy resin can provide an additional performance check where cure consistency is critical.

WHY SOLIDS CONTENT MATTERS

Solids content determines how much active curing agent is delivered by a given wet weight. A lower-than-normal solids level would introduce more water and less reactive hardener.
This can alter stoichiometry, drying time and film build. A higher-than-normal solids level can increase viscosity and reactive concentration.
Consistent solids are therefore central to manufacturing control.

WHY VISCOSITY MATTERS

Viscosity affects pumping, mixing, dilution and application preparation. ARADUR 35-1 is relatively viscous as supplied, so temperature control is important.
A batch tested cold may appear outside specification even when the composition is normal. The sample should be equilibrated to 25°C for meaningful comparison with published data.
Unexpected permanent viscosity change can indicate concentration drift, degradation or contamination.

WHY AMINE VALUE MATTERS

Amine value is a chemical fingerprint of the curing-agent functionality. It provides a sensitive indication of whether the product remains within the intended compositional range.
A large deviation can change cure ratio and final properties.
Amine value should be used together with solids and viscosity rather than as the only quality criterion.

TDS, SDS AND COA

The current Technical Data Sheet should be used to confirm specification values, mix ratios, dilution guidance, storage conditions and application recommendations.
The Safety Data Sheet governs hazard classification, component disclosure, PPE, first aid, firefighting, transport and disposal.
The Certificate of Analysis can provide batch-specific values for controlled properties where supplied. Historical brochures are useful for technical context but should not replace current regulatory documentation.

SAFETY AND HANDLING

ARADUR 35-1 is a reactive amine-containing curing agent and should be handled according to the current SDS. Waterborne form reduces conventional solvent vapor but does not eliminate the chemical hazards associated with reactive amine functionality.
Suitable gloves, eye protection and protective clothing should be used. Skin contact should be minimized because epoxy hardeners can cause irritation and sensitization.
Good ventilation remains appropriate during mixing and application, especially because the resin side or other formulation components may contain volatile materials.

SKIN CONTACT

Repeated skin exposure to amine hardeners can cause irritation and sensitization. Contaminated skin should be washed promptly with appropriate cleansing materials and water.
Organic solvents should not be used for skin cleaning because they can increase penetration and irritation.
Contaminated clothing should be removed and cleaned before reuse where appropriate.

EYE CONTACT

Splash protection is important during transfer, dilution and mixing. If product enters the eyes, immediate rinsing with plenty of clean water should begin and medical advice should be obtained according to the SDS.
EYE exposure can occur even in waterborne systems because high viscosity can cause splashing during pumping or stirring.

INHALATION

At ambient temperature, inhalation risk is generally less dominated by organic solvent vapor than in solvent-cut hardeners. Aerosols generated during spraying or high-energy mixing should still be controlled.
Respiratory protection should be selected based on the complete coating and actual exposure assessment.
Ventilation should also control any volatile material present on the resin side.

INGESTION

ARADUR 35-1 is an industrial reactive chemical and must not be ingested. Food and drink should be kept away from chemical handling areas.
After accidental ingestion, follow the current SDS and obtain medical advice.

SPILL MANAGEMENT

A spill can create a slippery surface because ARADUR 35-1 is a viscous aqueous liquid. The material should be contained and collected while preventing uncontrolled discharge to drains.
Absorbent or pumping methods should be selected according to spill size and site procedure.
Recovered contaminated material should be disposed of in accordance with local requirements and SDS guidance.

FIRE RESPONSE

The water content and high flash point reduce flammability relative to solvent-rich hardeners, but the organic component can decompose or burn under strong heating.
Combustion or thermal decomposition can generate carbon monoxide, carbon dioxide, nitrogen oxides and other toxic gases and vapors.
Fire response should follow the SDS and site emergency plan.

STORAGE

The product information recommends storage in a dry place, preferably in the sealed original container, at approximately 2-40°C. Direct sunlight should be avoided.
The product has historically been described as having a shelf life of several years when stored appropriately, with the expiry date on the original container controlling actual shelf life.
Freezing or excessive heat should be avoided because they can alter colloidal structure, viscosity and handling.

DILUTED PRODUCT STORAGE

Further-diluted ARADUR 35-1 can be less stable than the original commercial concentration. Slight turbidity can develop, and high temperature can increase the risk of phase instability.
Diluted material should therefore be prepared using controlled water quality and used within a validated period.
Bulk storage of highly diluted hardener should only be adopted after stability testing.

REGULATORY CONSIDERATIONS

Current product information identifies ARADUR 35-1 as VOC-free and SVHC-chemicals-free. These declarations are time-sensitive and should be verified from current supplier documentation when formal compliance is required.
The product is a proprietary mixture, so regulatory inventory and hazard status depend on all components and regional rules.
Use in primers, packaging-related coatings or other specialized markets does not automatically establish food-contact, potable-water or other regulatory approval of the finished coating.

ENVIRONMENTAL CONSIDERATIONS

Waterborne form can reduce emissions of conventional organic solvent, supporting lower-VOC coating technology.
Uncured amine-containing material should nevertheless not be discharged directly to surface water, soil or sewer systems.
Wastewater from equipment cleaning can contain reactive resin, hardener, pigments and additives and should be managed under applicable local rules.

COMMON FORMULATION PROBLEMS

Poor film coalescence
Low temperature, excessive water or an unsuitable resin dispersion can prevent formation of a continuous film. Improve drying conditions or adjust the resin/coalescent system.

Slow drying
High humidity, low airflow, excessive film thickness or too much dilution can retain water. Improve ventilation and reduce unnecessary water.

Short pot life
High temperature, highly reactive resin or catalytic pigments can shorten the usable window. Standardize material temperature and formulation.

Loss of gloss
Poor coalescence, foam, surface contamination or excessive pigment volume can reduce gloss. Optimize flow, defoaming and drying conditions.

Poor corrosion resistance
Incorrect mix ratio, low film thickness, weak surface preparation or unsuitable pigment package can reduce protection. Verify the complete primer system.

Poor adhesion
Dust, oil, concrete laitance, soluble salts or substrate moisture can reduce bonding. Correct surface preparation before reformulating.

Phase instability
Excessive dilution, high electrolyte level or incompatible additives can destabilize the waterborne hardener-resin system. Evaluate dilution and addition sequence.

Excessive viscosity
Low material temperature, insufficient water adjustment or formulation advancement can increase viscosity. Confirm temperature and pot-life stage before dilution.

Foaming
High-speed mixing, unsuitable surfactants or incorrect defoamer can create persistent foam. Optimize mixing and defoamer package.

Early water sensitivity
Insufficient cure or trapped water can cause whitening or softening. Allow full drying and cure before water exposure.

Sagging
Excessive dilution or low rheological structure can reduce vertical hold. Adjust water and rheology modifier levels.

FREQUENTLY ASKED QUESTIONS

What is ARADUR 35-1?
ARADUR 35-1 is a waterborne polyamine-adduct epoxy curing agent supplied in water.

What is the solids content?
Approximately 51-55% by weight.

What is the viscosity?
Approximately 19-35 Pa·s at 25°C.

What is the amine value?
Approximately 100-120 mg KOH/g.

What is the active hydrogen equivalent weight?
Approximately 380 g/eq as supplied.

What is the density?
Approximately 1.08 g/cm³ at 20°C.

What is the flash point?
Greater than approximately 100°C.

Is ARADUR 35-1 VOC-free?
ARADUR 35-1 as VOC-free.

Is ARADUR 35-1 benzyl-alcohol-free?
Published selector information identifies the grade as benzyl-alcohol-free.

What is the recommended ratio with ARALDITE GY 776?
Approximately 100 parts ARALDITE GY 776 to 200 parts ARADUR 35-1 by weight.

What is the recommended ratio with ARALDITE PZ 33757/67?
Approximately 100 parts resin to 144 parts ARADUR 35-1 by weight.

Can the mix ratio be adjusted?
About ±10% in the referenced system, with more hardener favoring flexibility and adhesion and less favoring anti-corrosion performance.

What is the pot life?
Older selector literature gives approximately 90 minutes with ARALDITE GY 776 under the referenced conditions.

Can ARADUR 35-1 be diluted with water?
Yes, but further dilution can create slight colloidal turbidity and should be validated for stability.

What are the main applications?
Waterborne epoxy primers, anti-corrosion coatings, mineral-substrate primers and related industrial coating systems.

Is ARADUR 35-1 suitable for concrete?
Yes. 

Does ARADUR 35-1 have one CAS number?
No single CAS number should be assigned to the complete proprietary trade grade without confirmation from the current SDS.

How should ARADUR 35-1 be stored?
Store dry in the sealed original container at approximately 2-40°C and protect it from direct sunlight.

Why is ARADUR 35-1 used in anti-corrosion primers?
It combines epoxy curing, strong adhesion, waterborne compatibility and a film profile suited to protective coatings.

What documents should be checked before use?
Use the current TDS, SDS and batch-specific COA where available.

FINAL TECHNICAL SUMMARY

ARADUR 35-1 is a waterborne polyamine-adduct curing agent developed for two-component aqueous epoxy systems. It is designed primarily for primers and related protective coatings where low VOC, strong adhesion, anti-corrosion protection, high gloss and good flow are desired.
The commercial product is supplied as a clear to slightly turbid liquid containing approximately 51-55% solids. Published technical data specify approximately 19-35 Pa·s viscosity at 25°C, 100-120 mg KOH/g amine value, about 380 g/eq active-hydrogen equivalent and a typical density near 1.08 g/cm³.
ARADUR 35-1 should not be treated as one pure molecular compound. It is a proprietary waterborne polyamine-adduct mixture, and one fixed molecular formula, molecular weight or universal CAS number should not be assigned to the complete grade without current SDS confirmation.

The hardener reacts with epoxy groups to create a three-dimensional thermoset network. At the same time, water must evaporate and the resin phase must coalesce into a continuous film. Successful waterborne epoxy performance therefore depends on both chemical cure and physical drying.
Current information identifies ARADUR 35-1 as VOC-free, SVHC-chemicals-free and suitable for primer applications on mineral substrates. Key product features include anti-corrosion protection, excellent adhesion, high gloss and improved flow.
Historical technical data recommend approximately 100:200 parts by weight for ARALDITE GY 776 / ARADUR 35-1 and approximately 100:144 for ARALDITE PZ 33757/67 / ARADUR 35-1. These values are resin-specific and should not be transferred automatically to other epoxy grades.

The PZ 33757/67 guidance historically allows about ±10% variation from the recommended hardener level. More hardener can increase flexibility and adhesion, while less hardener can improve anti-corrosion protection. The adjustment reflects changes in network stoichiometry and should remain within validated limits.
Selector literature gives a pot life around 90 minutes with ARALDITE GY 776, while newer coating-selector information provides a gel-time value around 70 minutes under its referenced protocol. These values are useful for comparison but should not be treated as universal field pot life.
ARADUR 35-1 can also be used with ARALDITE PZ 3961-1 waterborne epoxy dispersion. 

The product can be further diluted with water, but slight colloidal turbidity may develop. Historical technical guidance indicates that highly diluted mixtures can become less stable at temperatures above approximately 40°C, so dilution and storage conditions should be controlled.
Waterborne anti-corrosion primers, concrete and mineral-substrate primers, direct-to-metal systems, industrial maintenance coatings, high-gloss waterborne epoxy coatings and selected warm-curing systems are relevant application areas.
Film coalescence is essential. Low temperature, high humidity or excessive water can delay drying and leave a porous or soft film. Controlled airflow, substrate temperature and appropriate film thickness improve water removal and cure development.

Anti-corrosion performance depends on the complete system, including resin, hardener, pigment package, surface preparation and dry-film thickness. ARADUR 35-1 provides the reactive crosslinking component but does not replace corrosion-inhibitive pigments or proper substrate preparation.
Quality control should focus on solids content, viscosity, amine value, color and appearance. Functional cure testing with a standardized resin can provide additional assurance of batch-to-batch consistency.
ARADUR 35-1 should be stored in sealed original packaging at approximately 2-40°C, protected from direct sunlight and unnecessary contamination. Current SDS and supplier documentation should govern all handling, safety, transport and disposal requirements.
For ARADUR 35-1 technical specifications, application guidance, TDS, SDS, COA and formulation information, contact ATAMAN KIMYA with the intended epoxy resin system, substrate, coating type and performance requirements.

ATAMAN KIMYA
Phone: +90 216 577 10 10
Email: info@atamankimya.com