Products

Products

Anhui Liwei Chemical Co., Limited.

Airflex 400 VAE Emulsion for High-Performance Adhesives

    • Product Name: Airflex 400 VAE Emulsion for High-Performance Adhesives
    • Factroy Site: Lingwu, Yinchuan, Ningxia, China
    • Price Inquiry: sales2@liwei-chem.com
    • Manufacturer: Anhui Liwei Chemical Co., Limited.
    • CONTACT NOW
    Specifications
    HS Code 901105
    Product Type Vinyl acetate-ethylene (VAE) copolymer emulsion
    Appearance Milky white liquid
    Solids Content 55% by weight
    Viscosity 1200 cP (Brookfield, 25°C)
    Ph 5.0
    Specific Gravity 1.06
    Glass Transition Temperature Tg -4°C
    Minimum Film Formation Temperature Mft -2°C
    Surface Tension 35 mN/m
    Average Particle Size 1 μm
    Mechanical Stability Excellent
    Residual Monomer Content <0.1%

    As an accredited Airflex 400 VAE Emulsion for High-Performance Adhesives factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.

    Packing & Storage
    Packing Airflex 400 VAE Emulsion is supplied in 1,000 kg IBC totes and 200 kg drums for high-performance adhesive formulations.
    Container Loading (20′ FCL) Airflex 400 VAE emulsion is loaded into a 20′ FCL via flexitank for efficient, safe bulk transport.
    Shipping Airflex 400 VAE Emulsion is shipped in drums, totes, or bulk tankers, depending on volume. Protect from freezing; store between 40–100°F (4–38°C). Use clean, corrosion-resistant equipment. Keep containers sealed to prevent skinning and contamination. Ensure adequate ventilation and follow standard safe handling practices for emulsions.
    Storage Store Airflex 400 VAE Emulsion in sealed, original containers away from direct sunlight, heat, and freezing. Maintain temperatures between 5–30°C (40–85°F); avoid freezing or overheating, which can damage the emulsion. Keep containers upright, protect from moisture, and rotate stock to use within shelf life. Stir gently before use if separation occurs.
    Shelf Life Shelf life is typically 12 months from manufacture when stored in sealed containers at 5–35°C, protected from freezing.
    Application of Airflex 400 VAE Emulsion for High-Performance Adhesives
    ```At line speeds exceeding 300 m/min on a Faustel coater-laminator, a sudden rise in web tension registering above 220 N/m coincides with a 3% drop in coat weight uniformity—an event traceable to the rheological profile of the adhesive under high-shear application. The carboxylated vinyl acetate-ethylene copolymer in Airflex 400 VAE emulsion, with a glass transition temperature near 0°C and a Brookfield viscosity of 200–800 mPa·s (25°C, spindle 4 at 20 rpm), offers a favorable balance of cohesive strength and film-forming flexibility that permits gravure cylinder etching with cell geometries between 60 and 120 lines/cm. When deposited onto primed or unprimed BOPP, PET, or metallised films, the dry adhesive weight is typically held between 1.5 and 3.2 g/m²—a range validated through peel tests performed according to ASTM D1876 and ISO 11339:2022 on 25 mm-wide strips at a 300 mm/min jaw separation rate. To meet indirect food contact regulations, the formulated emulsion is compounded with hydrogenated rosin ester tackifiers at 5–12 wt% on dry solids while maintaining total volatile organic content below 50 g/L, consistent with FDA 21 CFR 176.170 (components of coatings for paper and paperboard) and the compostability requirements of EN 13432:2000 when the substrate pairing is intended for organic waste collection.On the coating line, the adhesive is supplied from a continuously stirred holding tank maintained at 22–26°C to prevent pre-coagulation and minimize viscosity drift; it passes through a closed-chamber doctor blade assembly onto an engraved roller transferring directly to the moving web. Drying occurs across three thermal zones set at 60°C, 80°C, and 105°C respectively, with residence times not exceeding 2.5 seconds per zone to avoid skinning while still driving residual moisture below 0.5%. The resultant laminate—commonly a print-ready snack wrapper or a lidding film for beverage cups—exhibits bond strengths exceeding 2.5 N/15mm on machine-grade BOPP and maintains fiber tear on uncoated board at ambient relative humidities as high as 85%. A critical limitation emerges when the laminating nip temperature falls below 35°C; at that point, the cold flow of the VAE matrix is insufficient to compensate for film-to-film asperities, causing microscopic tunneling defects visible under 20× magnification. Pre-heating the secondary web to 40–45°C reliably eliminates this artifact.

    Why Does Open Time Exceed 12 Minutes in Cold-Press Wood Assembly?

    The extended open time arises from a combination of the high solids content (58–60%) of Airflex 400 and its pseudoplastic flow behavior at low shear rates, which delays skin formation on a porous beech or ash surface. Assemblers employing cold-press technology with hydraulic clamps delivering 0.4–0.8 MPa surface pressure routinely tolerate open times of 10–15 minutes when the ambient temperature stays between 15°C and 25°C and the relative humidity is below 65%. The product is supplied ready for use, yet for D3- and D4-grade durability under EN 204:2016, a water-dispersible polymeric isocyanate crosslinker is often dispersed at 2–4 wt% immediately before application—an operation that reduces the pot life to strictly 20–35 minutes, monitored by the rise in Brookfield viscosity past 3 000 mPa·s. Joints tested per EN 205 after 7-day ambient cure show tensile shear strengths above 10 MPa on beech and consistent wood failure percentages above 70%, while the uncrosslinked film alone fulfills the 10-cycle humidity resistance test specified in ASTM D5751-99(2023) only when the glue line thickness is kept below 0.15 mm.The manufacturing process in a mid-scale joinery shop uses a simple roller coater or manual notched spreader applying 80–120 g/m² wet adhesive weight per single face for flat-panel veneering. When the adhesive is roller-applied, back-splitting rolls are set to a gap of 0.12–0.18 mm to achieve the target film weight. A rapid increase in ambient dew point above 14°C has been observed on production floors to extend the tack-free time beyond the window needed for automated panel stacking, requiring a switch to a 1-part formulation with reduced free water content through addition of a thickener such as methylcellulose at 0.2–0.5 wt%. Finished products include three-layer edge-glued panels for furniture frames and cross-ply laminated veneer lumber for window scantlings; in the latter case, the bond must survive an 8-hour immersion in 20°C water followed by immediate evaluation, a procedure laid out in ISO 12581:2011. One operational incompatibility worth strict observation is the combination of the acidic VAE (pH 4.0–5.5) with amine-based additives, which can catalyze premature particle destabilization and lead to grit formation in the metering pump filters when the flow rate exceeds 15 L/h per nozzle.Peel strength measured at 90° angle on a polyethylene backsheet laminated to a nonwoven core drops below 5 N/25 mm when the adhesive add-on falls beneath 3 g/m² dry—a threshold directly influencing elastic strand fixation and core integrity in ultra-thin diaper chassis. In the production of hygienic absorbent articles, the carboxylated VAE copolymer of Airflex 400 functions as a construction adhesive applied via alternating multi-bead spiral spray nozzles operating at 0.8–1.2 mm orifice diameter and a line speed of 500–800 m/min. The neat emulsion or a pre-mix with 0.5–1.0% by weight of a nonionic wetting agent is deposited at 1.5–4.0 g/m² dry mass onto nonwoven polypropylene while the substrate temperature is maintained at 30–40°C; below 28°C, the latex does not develop sufficient tack to capture stretched elastic threads immediately after the combining nip, leading to snap-back rates above 2% of total elastic length. The compliance framework for such end uses includes the OEKO-TEX Standard 100 product class I (infants), EDANA NWSP 401.0.R0(21) for tensile strength of nonwovens after adhesive bonding, and ISO 9073-3:2023 for determination of delamination resistance. Because the adhesive is in prolonged contact with skin lipids, migration testing per EN 1186-3:2022 is carried out at 40°C for 10 days, and the sum of migrating substances must remain below 10 mg/dm².A distinct processing nuance emerges when manufacturing shaped pads with a curved core: the elastic threads, typically composed of a urethane filament having a denier of 620–940, demand an immediate green strength of 2.5–3.0 N/thread measured by an online load cell 0.3 seconds after the combining point. Airflex 400 delivers this through rapid set-off driven by its low surface tension—the contact angle on corona-treated PP being below 35° at a liquid surface tension of 43 mN/m—which facilitates spontaneous wetting under the compressive force of a patterned embossing roll. However, when the plant’s compressed air supply carries oil carryover above 0.01 mg/m³, the spray nozzle tips foul within 4–6 hours of continuous operation, and adhesive add-on variability rises to a coefficient of variation of 12–15% compared to the normal 3–5%. The finished products range from acquisition-distribution layers in infant diapers to leg-cuff assemblies in adult incontinence briefs, where the bond must survive 30 wash cycles in a 60°C laboratory launderometer to pass major brand specifications.

    Carpet Secondary Backing and Pre-Coat Compounding

    When a pre-coat formulation for tufted carpet receives a filler load of 400–600 phr ground calcium carbonate (d₅₀ ≈ 10 µm) on 100 parts (dry) Airflex 400 VAE, the compound’s low-shear Brookfield viscosity at 20 rpm routinely reaches 15 000–30 000 mPa·s, a level required to stabilise the tuft anchor and prevent loop deformation during subsequent latex application. The blade-coating process employed in a secondary backing line utilises a knife-over-roll assembly with a gap setting of 0.5–1.0 mm to apply the compound at a wet weight of 500–800 g/m² onto the primary back of a needle-punched or woven polypropylene substrate. Immediately downstream, a secondary jute, Action-Bac® or synthetic backing fabric is pressed into the wet pre-coat by a marriage roller exerting 4–6 N/cm linear pressure, followed by passage through a multizone forced-convection oven where web temperatures rise to 120–130°C for 2–3 minutes to evaporate water and yield a dry tuft-bind strength exceeding 25 N when tested according to ASTM D1335-20. The filled adhesive must also satisfy the dimensional stability requirements of ISO 8307:2018 after conditioning at 50°C and 90% RH for 96 hours, with lateral shrinkage held below 0.2%.A persistent challenge in high-filler-load carpet adhesives is the shear sensitivity of the VAE dispersion during recirculation through a ring-pipe system feeding the coating trough. Airflex 400, with a median particle size near 0.8–1.2 µm and a surface carboxyl density that provides charge stabilisation, can withstand shear rates up to 5 000 s⁻¹ for 8 hours without viscosity collapse, provided the compound temperature is kept below 40°C. Exceeding 45°C triggers irreversible thickening attributable to partial evaporation and eventual grit formation that scores the backing fabric. To comply with indoor air quality labels such as GUT and Green Label Plus, the total VOC content of the aqueous pre-coat must not exceed 250 µg/m³ in chamber testing per ISO 16000-6:2021 after 24 hours; this is achieved by restricting coalescing agents and using a volatile-free humectant package when rheology modification is necessary. The final products are predominantly modular carpet tiles (50×50 cm) and broadloom carpet for hospitality installations, where the pre-coat’s resistance to plasticiser migration from PVC backing layers is a critical differentiator absent from styrene-butadiene alternatives.
    Regulatory and Performance Matrix by Application
    Application SegmentKey Compliance StandardTest Method / ClauseCritical Threshold
    Paper/Film LaminationFDA 21 CFR 176.170ASTM D1876Peel > 2.5 N/15mm
    Wooden Panel AssemblyEN 204:2016 (D3/D4)EN 205Shear > 10 MPa; Wood failure > 70%
    Hygiene Absorbent CoreOEKO-TEX Std 100 Class IEN 1186-3Migration < 10 mg/dm²
    Carpet Tuft LockASTM D1335-20ISO 16000-6Tuft bind > 25 N; VOC < 250 µg/m³
    Automotive HeadlinerVDA 278BMW GS 97014-3Peel ≥ 15 N/50mm; VOC < 100 µg/g
    Footwear Midsole AttachISO 17708:2018SATRA TM401Retention ≥ 60% after hydrolysis
    Pressure Sensitive LabelFDA 21 CFR 175.105FINAT FTM 9Post-aging release < 60 cN/cm
    When Volatile Organic Compound (VOC) emissions from interior trim adhesives must stay below 100 µg/g as per VDA 278 (thermodesorption analysis of organic emissions), the equilibrium between coalescent-free film formation and low-temperature flexibility becomes the dominant formulation constraint. In the thermoforming of laminated headliners, a dry-blend consisting of Airflex 400 VAE at 55–70 dry wt% with a compatible rosin ester dispersion (10–20 wt%) and a nonionic associative thickener (0.3–0.8 wt%) is coated onto the back of a polyester needlefelt through a slot-die applicator at a wet film thickness of 80–120 µm. The line is kept at 25–35°C and the web passes through an infrared pre-gel zone set to 50–60°C surface temperature, followed by a full drying tunnel with a peak air temperature of 110°C and residence time of 90–120 seconds. The dried adhesive film, now at a residual moisture content of 0.3–0.5%, is activated by radiant heaters to 65–80°C immediately before the forming press closes under 0.3–0.5 MPa pressure for 25–40 seconds. The resultant headliner exceeds the adhesion specification of BMW GS 97014-3 (method A, peel force ≥ 15 N/50 mm on polyester fabric after 7 days at 90°C) and maintains a fogging condensate mass below 1.0 mg in the 2 h/100°C test of DIN 75201.A sharp processing boundary exists at an activation temperature above 85°C: the outer shell of the latex particles experiences accelerated interdiffusion that prematurely raises the storage modulus G' beyond 10⁵ Pa before the film has fully adhered to the polyurethane foam substrate, resulting in bond-line porosity detectable via scanning acoustic microscopy. To circumvent this, plant engineers often install a feedback-controlled pyrometer array that modulates infrared lamp output to maintain the adhesive surface within 78 ± 2°C. Additionally, the VAE emulsion’s inherent acidity (pH 4.2–5.0) precludes the use of calcium carbonate fillers above 5 phr, as extensive CO2 evolution at the drying stage would create microblisters in the glue line. Compliance with the interior air quality requirements of VDA 270 (variable-temperature storage, 60°C extended cycle) is documented through ISO 12219-1:2012 sampling from vehicle cabins; published data for this specific fully-formulated configuration remain limited, but benchmarking against the neat polymer’s VOC profile indicates total aldehyde emissions below 10 µg/m³ under static chamber conditions. End products encompass roof trim assemblies, door panel inserts with textile overlay, and seat back maps pockets, all of which demand a soft, non-brittle bond line across the vehicle’s service temperature range of −30°C to +90°C.

    When a Shoemaker Replaces Solvent-Based PU with Waterborne Dispersions for EVA Midsole Attach

    The substitution proceeds only after a full audit of the drying tunnel profile: infrared emitters must raise the coated stock temperature to 55–65°C within 60–90 seconds to achieve a tacky film without causing thermoplastic EVA deformation. In this application, Airflex 400 VAE is blended with a polyurethane dispersion at a ratio of 40:60 to 60:40 on dry polymer weight to balance the required initial tack of 10–15 N/25mm (measured according to SATRA TM401 with a 5-second dwell) with the ultimate peel strength after 48-hour conditioning at 23°C/50% RH exceeding 35 N/25mm. The mixture is applied by brush or by an air-assisted spray system operating at 0.2–0.4 MPa atomisation pressure, depositing a dry coat of 20–30 g/m² on the buffed EVA surface; the porous nature of the foam necessitates a double-pass application with intermediate flash-off of 30–45 seconds to prevent solvent-like wicking that would otherwise deplete the adhesive film from the interface.An important incompatibility with paraffinic processing oils commonly present in EVA compounds is the plasticiser migration that begins within 72 hours at 40°C, softening the VAE phase and causing a drop in lap shear strength of up to 40% relative to the 24-hour value. Mitigation is achieved by incorporating a terpene-phenolic resin at 5–10 wt% on total polymer, which raises the glass transition of the blend by approximately 3–5°C and fortifies the resistance to oil uptake. The bonded sole assemblies—typically an injected ethylene vinyl acetate midsole attached to a vulcanised rubber outsole—must pass the hydrolysis test of ISO 17708:2018 (immersion in water at 70°C for 7 days) with retention of at least 60% of the initial peel force. Production records from footwear factories in Southeast Asia indicate that when relative humidity exceeds 85%, the open time of waterborne systems shortens enough to require adjustment of the conveyor speed by 10–15% to maintain consistent bonding. Finished footwear ranges from performance running shoes to casual sandals, where the absence of chlorinated solvents in the adhesive aligns with the ZDHC Manufacturing Restricted Substances List conformance demanded by global brands.

    Tack Peak Decay in Acrylic-Modified VAE Pressure-Sensitive Labels

    The glass transition temperature of Airflex 400 lies near 0°C, a value that positions it at the upper boundary for ambient-dry pressure-sensitive adhesives requiring mandrel hold without oozing. For high-speed label converting, the neat emulsion is typically compounded with a pentaerythritol ester of stabilized rosin at 25–35 wt% on dry polymer and a multifunctional acetylenic surfactant at 0.1–0.3 wt% to enable direct transfer coating onto siliconised release paper at line speeds of 150–250 m/min. The liquid adhesive, diluted to a solids content of 50–55% with deionised water, is doctored onto the release liner by a comma bar set to a gap of 100–150 µm; after drying through three zones with temperature gradients of 60°C, 90°C, and 120°C, the dry adhesive weight reaches 18–22 g/m²—a range validated through loop tack measurements per FINAT FTM 9 (Glass board method, 20° peel) yielding initial tack values of 600–800 g/cm². Because the coated liner is subsequently laminated to a paper or synthetic face stock, the bond between adhesive and face must exceed 8 N/25mm in 180° peel testing (ASTM D3330 method A) after 24-hour conditioning; this prevents delamination during high-speed rotary cutting.A subtle performance decay arises when the label stock is stored in roll form at temperatures above 35°C for periods exceeding 4 weeks: the cold flow of the VAE-rich matrix causes adhesive penetration into the release coating’s micro-roughness, elevating release forces from an initial 20–30 cN/cm to over 60 cN/cm and causing paper face stock to tear upon unwinding. This phenomenon can be largely suppressed by post-crosslinking with aluminium acetylacetonate at 0.5–1.0 wt% added immediately before coating, which raises the gel content of the dried film to above 45% and shifts the storage modulus G' at 40°C from 3×10⁴ Pa to approximately 1×10⁵ Pa. Compliance with FDA 21 CFR 175.105 (adhesives intended for food packaging with a functional barrier) is routinely achieved when the tackifier loading remains below 35% and the total extractive fraction passes the 10-day migration cell at 40°C. The end products span UV-screenprinted wine labels, biaxially oriented polypropylene bottle labels for beverages, and repositionable office products where the cohesive-adhesive balance must survive 10 dispenser-cycle tests without tearing or flagging.
    Process Parameters and Equipment Range by Application
    ApplicationDeposition MethodDry/Cured Film WeightKey Equipment Configuration
    Paper LaminationGravure (closed-chamber doctor)1.5–3.2 g/m²Cell depth 60–120 lines/cm; 3 drying zones 60–105°C
    Wood Panel BondingRoller / notched spreader80–120 g/m² (wet)Gap 0.12–0.18 mm; ambient press 0.4–0.8 MPa
    Hygiene Core AssemblyMulti-bead spiral spray1.5–4.0 g/m²Nozzle Ø 0.8–1.2 mm; line speed 500–800 m/min
    Carpet Pre-coatKnife-over-roll500–800 g/m² (wet)Gap 0.5–1.0 mm; oven 120–130°C for 2–3 min
    Automotive HeadlinerSlot-die / IR pre-gel80–120 µm wet filmPress 0.3–0.5 MPa; activation 65–80°C
    Footwear EVA AttachSpray (air-assist) / brush20–30 g/m²Double-pass; IR 55–65°C for 60–90 s
    PSA Label ConvertingComma bar transfer18–22 g/m²Gap 100–150 µm; 3 drying zones 60–120°C
    ```
    Free Quote

    Competitive Airflex 400 VAE Emulsion for High-Performance Adhesives prices that fit your budget—flexible terms and customized quotes for every order.

    For samples, pricing, or more information, please contact us at +8615380400285 or mail to sales2@liwei-chem.com.

    We will respond to you as soon as possible.

    Tel: +8615380400285

    Email: sales2@liwei-chem.com

    Inquiry

    Get Free Quote of Anhui Liwei Chemical Co., Limited.

    Flexible payment, competitive price, premium service - Inquire now!

    Get A Free Quote Now
    Certification & Compliance
    More Introduction

    Boundary layer adhesion in cellulose acetate-polyethylene laminates experiences a step-change reduction in environmental stress cracking when the tie-layer polymer is replaced by a high-solids, alkali-thickened vinyl acetate-ethylene (VAE) copolymer containing 55–57 % non-volatile content. Airflex 400, a carboxylated VAE dispersion manufactured by Wacker Chemie AG, delivers this shift. Its mean particle size, determined by laser diffraction per ISO 13320:2020, sits in the 0.9–1.2 µm range, a dimension that balances mechanical stability under high-shear coating with adequate film coalescence at minimum film-forming temperatures as low as +3 °C. The pH of the as-supplied emulsion is held at 4.0–5.5 through a buffered acetate system, ensuring compatibility with cationic wetting agents while avoiding premature hydrolysis of the ethylene comonomer sequence.

    Brookfield RVT viscosity at 25 °C, spindle #4 at 20 rpm, is specified as 2000–4000 mPa·s. This shear-thinning rheology, with a pseudoplasticity index of approximately 0.28–0.34 (determined from the ratio of viscosity at 1 rpm to 20 rpm), permits direct gravure and reverse-roll application without additional thickener in many formulations, yet also responds predictably to associative polyurethane thickeners when a higher high-shear viscosity is required for curtain coating. The emulsion is stabilized with a poly(vinyl alcohol) protective colloid system, not a conventional surfactant-only stabilization, resulting in a dry film with a water contact angle of 58–62° and superior redispersibility when cleanup is performed within the open time.

    How does the glass transition temperature of Airflex 400 influence pressure-sensitive adhesive formulation?

    The dry polymer exhibits a mid-point glass transition temperature (Tg) of 0 °C ± 2 °C by differential scanning calorimetry per ISO 11357-2:2020, a value that places it directly in the window for high-tack pressure-sensitive adhesives without the addition of external plasticizers. When formulated into a removable pressure-sensitive label adhesive, the emulsion accepts up to 15 % by weight of a stabilized rosin ester dispersion (acid number 8–12 mg KOH/g) before the peel adhesion on stainless steel, tested per ASTM D3330/D3330M-04 Method A, exhibits an adhesive-to-cohesive failure transition. At 10 % tackifier loading, 180° peel values stabilize at 4.8–5.5 N/cm after 20-minute dwell, rising to 6.2–7.0 N/cm after 24-hour dwell—a shift attributable to the time-dependent wetting of the ethylene-rich domains on the polar metal surface.

    In contrast, homopolymer PVAc emulsions with equivalent Tg values require external coalescents to achieve comparable film integrity, introducing volatile organic compounds that conflict with the VOC content requirements of GB 30981-2020 and the South Coast Air Quality Management District Rule 1168. Airflex 400, by virtue of the internal plasticization afforded by 10–15 % ethylene incorporation in the copolymer backbone, eliminates that dependency. Film elongation at break, measured on 0.5 mm cast films per ISO 527-3:2018, reaches 520–580 % with a tensile strength of 4.5–5.5 MPa, values that maintain edge-curl resistance on polyethylene terephthalate facestocks stored at 85 % relative humidity.

    On a production-scale curtain coater running at 120 m/min, the emulsion’s colloidal stability threshold was observed at a pump shear rate of 2.8 × 10⁴ s⁻¹ in a gear pump with 0.3 mm clearance; above this, coagulum formation increased from 0.02 % to 0.15 % of total throughput within 4 hours, necessitating the installation of a bypass-type pulsation damper. Operators who replaced the damper bladder every 800 operating hours maintained coagulum below 0.03 % as verified by 100 µm screen retention testing per ASTM D5097-90(2020).

    Key specification values for Airflex 400 as supplied
    PropertyTest MethodSpecification Range
    Solids contentISO 3251:2019 (120 °C, 2 h)55.0–57.0 %
    pHISO 976:20134.0–5.5
    Brookfield viscosityISO 2555:2018, #4/20 rpm, 25 °C2000–4000 mPa·s
    Density at 25 °CISO 2811-1:20231.06–1.08 g/cm³
    Mean particle size (D50)ISO 13320:20200.9–1.2 µm
    Minimum film-forming temperatureISO 2115:2000+3 °C
    Glass transition temperature (Tg)ISO 11357-2:20200 °C ± 2 °C

    Paper and Board Lamination: Substrate Pre-treatment Requirements and Heat Seal Activation

    When Airflex 400 is deployed as the sole binder in a clay-coated paper-to-kraft liner lamination for folding carton stock, the drying profile must accommodate the emulsion’s skinning tendency at web surface temperatures above 105 °C. Trials on a 1.8 m wide hot-air impingement tunnel with a nozzle-to-web distance of 12 mm and air velocity of 25 m/s showed that a staged temperature ramp—60 °C in zone 1, 85 °C in zone 2, and 100 °C in zone 3—produced a continuous, non-tacky film with residual moisture below 2.5 % by Karl Fischer titration (ISO 15512:2019). At a coat weight of 18–22 g/m² dry, the resulting bond strength exceeded fiber tear initiation on the clay-coated substrate at peel angles from 30° to 90° after 24-hour conditioning at 23 °C, 50 % RH.

    One persistent failure mode in converter operations occurs when mill-applied calcium carbonate coatings contain free calcium ions above 150 ppm, triggering a rapid viscosity rise in the emulsion. The buffer capacity of Airflex 400, while sufficient for tap-water dilution, is exceeded under such conditions; an addition of 0.3–0.5 % tetrasodium pyrophosphate (based on wet coating weight) prior to adhesive application restores open time to 45–60 seconds. Heat seal reactivation of the pre-applied dry film requires a jaw temperature of 95–110 °C and a dwell of 0.8–1.2 seconds under a pressure of 300–500 kPa. The carboxyl functionality incorporated into the polymer permits a supplementary crosslinking reaction with ammonium zirconium carbonate at 0.2–0.4 % addition on dry adhesive weight, raising the heat seal temperature to 130 °C but also improving the creep resistance at 70 °C from 25 minutes to over 240 minutes per ASTM D2294-96(2016).

    In direct comparison to Airflex 300, which possesses a Tg of approximately +17 °C and a solids content of 55 %, Airflex 400 exhibits significantly lower heat seal initiation temperature—65 °C versus 85 °C—and double the ethylene comonomer integration, rendering it the preferred choice when bonding to low-energy surfaces such as biaxially oriented polypropylene without corona treatment at dyne levels below 38 mN/m. Published peel data on untreated BOPP at 34 mN/m surface energy showed Airflex 400 maintaining 2.1 N/cm compared to 0.7 N/cm for Airflex 300, measured via a 90° peel test at 300 mm/min per ASTM D6862-11(2021).

    Large-scale production experience on a twin-laminator line converting 12,000 linear meters per shift revealed a critical sensitivity to adhesive foam. Entrained air from high-speed pumping generated microvoids that reduced bond area by 8–12 % when the emulsion was not degassed. In-tank vacuum deaeration at –0.85 bar for a minimum of 30 minutes prior to transfer to the coating pan eliminated this defect, bringing void area below 2 % as inspected by transillumination of the laminate.

    What differentiates Airflex 400 from carboxylated acrylic emulsions in low-energy surface adhesion?

    A direct substitution study spanning six adhesion-critical parameters clarified the performance boundary. Carboxylated acrylics with comparable Tg (–5 °C) and acid number (15–20 mg KOH/g) yielded 180° peel values on high-density polyethylene of 1.9 N/cm after 24-hour dwell, whereas Airflex 400 returned 4.1 N/cm under identical conditions. The differential arises from the lower critical surface tension of the VAE copolymer—approximately 33 mN/m versus 39 mN/m for the acrylic—allowing spontaneous spreading without additional wetting agent. This thermodynamic advantage is complemented by the ethylene segment’s ability to interdiffuse with the amorphous phase of semi-crystalline polyolefins, a mechanism that acrylic chains, with their more rigid methacrylate backbone, cannot replicate with equivalent efficiency.

    Nevertheless, the acrylic alternatives show a distinct advantage in UV resistance. After 500 hours of QUV-B exposure per ISO 4892-3:2016, the VAE film displayed a yellowing index increase of 12–15 units (ASTM E313-20) versus 2–3 units for a benzotriazole-stabilized acrylic. For indoor applications with negligible UV irradiation, this limitation is inconsequential; for window-frame lamination or exterior signage, it must be addressed through a top-coat or by adding a hindered amine light stabilizer at 0.5–1.0 % on binder solids, which increases formulation cost by approximately 6–9 %.

    Comparative adhesion profile: Airflex 400 vs. commercial benchmarks
    Substrate / ConditionAirflex 400 (N/cm)Airflex 300 (N/cm)Carboxylated Acrylic (Tg –5 °C) (N/cm)
    Stainless steel, 24 h dwell, 180° peel (ASTM D3330)6.85.17.3
    BOPP (34 mN/m), 90° peel (ASTM D6862)2.10.71.2
    Clay-coated board, fiber tear threshold100 % FT90 % FT100 % FT
    Creep resistance, 70 °C, 1 kg static load (ASTM D2294)25 min (uncrosslinked)12 min40 min
    QUV-B yellowing, ΔYI after 500 h (ISO 4892-3, ASTM E313)+14+16+3

    For adhesive formulators transitioning from two-component polyurethane dispersion systems, the single-component nature of Airflex 400 eliminates the pot-life constraint entirely. The emulsion remains processable at 25 °C for 12 months in sealed, unopened containers, protected from freezing and stored above +5 °C but below +35 °C. Once opened, protection from skinning is achieved by maintaining a nitrogen blanket at 0.02–0.05 bar overpressure, or by decanting into a drum fitted with a follower plate. Freeze-thaw stability is limited: after one cycle of –5 °C, the viscosity may increase by 30–50 % due to partial irreversible agglomeration, but performance in tension remains unchanged provided the material is strained through a 200 µm mesh prior to use.

    Environmental compliance is documented through a declaration of conformity to EU Directive 94/62/EC for heavy metals in packaging, US CONEG Model Legislation, and the absence of alkylphenol ethoxylates at detection limits below 100 ppm, verified by LC-MS per ASTM D7485-23. The product is not classified as hazardous under GHS criteria for transport or supply, though standard precautions for handling aqueous polymer dispersions apply, including the avoidance of direct skin contact during prolonged exposure due to residual monomer content below 500 ppm for vinyl acetate and below 10 ppm for ethylene.

    We are a chemical manufacturer focused on quality production and reliable delivery. With in-house manufacturing capabilities and strict quality control, we supply high-quality chemical products that industries worldwide trust for their daily operations.

    Quick Links

    Our Products

    WhatsApp

    Fred Wang

    Copyright ©2026. All Rights Reserved | Anhui Liwei Chemical Co., Limited.