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Anhui Liwei Chemical Co., Limited.

BJ-806H VAE Emulsion

    • Product Name: BJ-806H VAE Emulsion
    • Factroy Site: Lingwu, Yinchuan, Ningxia, China
    • Price Inquiry: sales2@liwei-chem.com
    • Manufacturer: Anhui Liwei Chemical Co., Limited.
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    Specifications
    HS Code 835404
    Product Name BJ-806H VAE Emulsion
    Chemical Type Vinyl acetate-ethylene copolymer emulsion
    Appearance Milky white liquid
    Solid Content Pct 55.0
    Viscosity Mpa S 2000
    Ph 5.5
    Density G Cm3 1.06
    Particle Size Um 1.5
    Glass Transition Temp C -14
    Minimum Film Forming Temp C 0
    Residual Vinyl Acetate Pct 0.5
    Ethylene Content Pct 16.0
    Film Appearance Transparent, flexible film
    Mechanical Stability Excellent
    Storage Stability Stable under recommended storage conditions

    As an accredited BJ-806H VAE Emulsion factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.

    Packing & Storage
    Packing BJ-806H VAE Emulsion is packaged in 200 kg drums, ensuring safe transport and storage.
    Container Loading (20′ FCL) 20′ FCL: 80 drums × 200kg net, palletized, secured with straps, shrink-wrapped for safe transport of BJ-806H VAE Emulsion.
    Shipping BJ-806H VAE Emulsion is shipped in sealed plastic drums or IBC totes, protected from freezing and direct sunlight. It is not classified as dangerous goods under standard regulations. Keep upright, avoid extreme heat, and transport in clean, dry containers to preserve emulsion stability.
    Storage Store BJ-806H VAE Emulsion in a cool, dry, well-ventilated area between 5–35°C, away from direct sunlight, frost, and heat sources. Keep containers tightly sealed to prevent surface film formation or contamination. Avoid contact with strong oxidants. Stir gently before use. Shelf life is typically 6 months from production date under proper storage.
    Shelf Life Shelf life is 12 months from manufacture if stored sealed, cool, and protected from freezing.
    Application of BJ-806H VAE Emulsion

    BJ-806H, a carboxyl-functionalized vinyl acetate-ethylene copolymer emulsion stabilized with a polyvinyl alcohol protective colloid, exhibits a glass transition temperature of approximately –15°C and a minimum film formation temperature below 0°C. These parameters dictate its processability in cold-weather application lines and its capacity to coalesce into a continuous film without external plasticizers across a 0°C to 5°C range—a property exploited in several of the industrial segments described below. The inherent ethylene comonomer content, maintained within 14–16 wt% according to pyrolytic-GC data from production batches, imparts permanent internal plasticization, which eliminates the exudation risk associated with low-molecular-weight ester plasticizers under cyclic thermal stress.

    Moisture-Insensitive Tile Adhesive Formulations and Open-Time Extension

    In cementitious tile adhesives conforming to EN 12004 classification C2E or C2TE, BJ-806H is introduced as a polymeric modifier at 3.5–5.0 parts per 100 parts dry mix, calculated on solids, to engineer extended open time without the moisture-sensitivity penalty typical of fully hydrolyzed PVA powders. The latex is post-added during the blending cycle in a horizontal ribbon mixer equipped with a high-shear chopper running at 1450 rpm, ensuring colloidal dispersion within the cement-graded silica fume matrix. The dispersion sequence requires a total mixing duration of 240 seconds, after which the system develops a pseudoplastic flow curve with a Casson yield stress between 28 Pa and 34 Pa, as measured by rotational rheometry at 20°C. Open time, evaluated per EN 1346 on absorbent concrete slabs conditioned for 20 minutes prior to tile embedding, exceeds 0.5 N/mm² tensile adhesion strength—surpassing the 0.5 MPa threshold mandated by the E classification. The ethylene segments generate a hydrophobic microdomain network that retards water loss from the mortar interface while maintaining sufficient capillary porosity for carbonation-induced strength development. Finished products include C2TE-grade thin-bed adhesives for large-format porcelain tiles, rapid-setting C2FT repair mortars with a 30-minute pot life, and exterior-grade wall-mount adhesives requiring constant sheer strength after 24-hour water immersion per EN 12004 clause 8.2.3.

    When BJ-806H Replaces Acrylic in Non-Woven Carpet Backcoating

    Tufted carpet secondary backcoating lines processing needle-punched polyester non-wovens at line speeds of 18–25 m/min utilize BJ-806H as a formaldehyde-free alternative to carboxylated styrene-butadiene latexes. The compound is applied via a knife-over-roll coating head with a gap set to 0.8–1.2 mm, depositing a wet film weight of 350–420 g/m². Drying occurs in a three-zone impingement oven with zone temperatures of 110°C, 130°C, and 120°C, achieving a residual moisture content below 1.2% before winding. The carboxyl functionality introduced during polymerization provides latent crosslinking sites that activate during thermal drying when formulated with 0.3–0.6 phr of a blocked isocyanate, raising the dried film’s insoluble gel fraction to 72–78% as determined by Soxhlet extraction in tetrahydrofuran for 8 hours. Compliance centers on GB 18587-2001 limits for volatile organic compound emissions from indoor floor coverings, with residual vinyl acetate monomer content in the latex controlled below 500 ppm via a post-polymerization oxidative initiation spike. The ethylene interpolymer backbone delivers a tuft lock value exceeding 3.2 kg per BS 6657:1992 test method using a 5 mm tuft pull probe, while the PVA colloid imparts rewettability critical for secondary backing lamination with a jute or action-back woven fabric. End products comprise contract-grade carpet tiles for commercial interiors, automotive trunk liners with Class B flammability ratings per FMVSS 302, and entrance matting systems with wet-delamination resistance exceeding 48 hours of continuous immersion.

    Aqueous laminating adhesives for wood veneer and high-pressure laminate bonding to medium-density fiberboard substrates depend on rapid wet tack development and a low swell response (≤0.3% edge swelling in beech veneer at 160 g/m² application weight). BJ-806H is compounded with 8–12% polyvinyl alcohol (DP 1700, 88% hydrolysis) to form a two-component system that is applied via roller coater with a chrome-plated gravure cylinder engraved at 40 lines/cm. Wet tack, measured as the time-dependent peel force on a tensile tester set to 300 mm/min jaw separation speed, reaches 2.8 N/25mm at 180 seconds open assembly time—a value comparable to urea-formaldehyde systems without their inherent formaldehyde-release concerns. The laminating process requires a cold press at 0.6–0.8 MPa for 45–60 minutes followed by 24-hour ambient conditioning. The press cycle timing is dictated by the coalescence rate of the VAE particles on the porous MDF surface, a process accelerated by the high ethylene content that reduces the minimum film-forming temperature below ambient. Tensile shear strength on beech lap joints, conditioned per EN 205 at 23°C and 50% RH for 7 days, exceeds 7.0 MPa, with wood failure percentages consistently above 80%. Applicable standards include ANSI/HPVA EF 2020 for laminated panel products—where the adhesive must pass a 3-cycle soak-and-dry test without delamination—and DIN 68705-2 for interior plywood. Typical laminate structures produced are office furniture desktops with melamine-faced chipboard, kitchen cabinet door fronts with cured phenolic backer sheets, and architectural wall panel systems requiring Class B surface flame spread per ASTM E84.

    Continuous-dip and blade-coat finishing of cotton-polyester blend workwear fabrics exploits the low-temperature flexibility of BJ-806H to generate handle modification without the stiffening effect of vinyl acetate homopolymer dispersions. The finish bath is prepared at 12–16% solids with the addition of 0.8 weight percent (on bath mass) of a nonionic wetting agent having a cloud point above 70°C and 2% of a blocked acid catalyst (amine-blocked p-toluene sulfonic acid) to promote subsequent curing at 145°C for 90 seconds in a stenter frame with overfeed set to 3%. The coating weight is controlled by padder nip pressure of 2.5 bar to deposit a dry add-on of 4.5–6.0 g/m². The VAE copolymer forms a discontinuous surface film that bridges individual fibers without cementing them into rigid bundles; this is evidenced by bending length reductions of 24–30% when tested according to BS 3356 (cantilever stiffness method) relative to untreated control samples. Shrinkage during subsequent home laundering per AATCC TM150 on a 5-cycle regimen is held below 1.8% in the warp direction. Compliance with the OEKO-TEX Standard 100 Annex 4 limits for residual monomer and polymer-bound auxiliaries is met through the low surfactant profile of the synthesis and the high-temperature devolatilization of unreacted species during latex production. Typical garments include industrial work shirts, anti-static cleanroom smocks, and flame-retardant over-trousers where the VAE film synergizes with phosphorus-based intumescent coatings without inhibiting char expansion.

    Low-Cement Self-Leveling Underlayment Compounds: Rheology Control and Surface Abrasion Resistance

    Calcium sulfate-based and ternary binder self-leveling mortars spread at a depth of 3–8 mm over heated floor systems require a controlled rheology profile that prevents rapid slump loss while maintaining a 240–260 mm flow cone spread diameter as per JC/T 985-2017 testing. BJ-806H is dispensed into the gauging water at a ratio of 4.5–6.0 weight percent of binder—typically a blended calcium sulfate hemihydrate and OPC system with a 0.28 water/binder ratio—and mixed in a continuous mixing pump equipped with a stator-rotor shear mixer running at 2850 rpm. The latex particles adsorb onto the hemihydrate crystal nucleation sites, retarding the hydration of the calcium sulfate phase by 8–12 minutes at 23°C, which extends the working time without the use of retarders that can reduce final compressive strength to below 25 MPa. Hardened surface abrasion resistance, measured by the Böhme abrasion test as referenced in EN 13813 for screed materials, improves by 35–40% relative to latex-free control mixes, with a wear depth not exceeding 2.5 cm³/50 cm². The VAE film network, formed during the dehydration of the mortar, bridges microcracks nucleating at the aggregate-paste interfacial transition zone, and its alkaline hydrolysis resistance—confirmed through accelerated aging in saturated Ca(OH)₂ solution at 40°C for 14 days—ensures long-term ductility. The system complies with EN 13813 designation “CT-C25-F5” for domestic and commercial floor rehabilitation, including bonded screeds on concrete, floating screeds over acoustic insulation mats, and heated floor overlays with thermal resistance below 0.15 m²·K/W to satisfy EN 1264-3 requirements.

    Paperboard lamination for cosmetic and medical packaging often employs solventless wet lamination processes where a single-component adhesive must achieve immediate fiber-tear bonds under light compression without the use of drying tunnels. BJ-806H is applied at 2.8–3.5 g/m² dry weight using a three-roll offset gravure applicator transferring a 42% solids-compounded formulation to a bleached kraft paper web moving at 120 m/min. The adhesive formulation includes a 0.2% defoamer (polyether siloxane copolymer) and a high-molecular-weight associative thickener (0.5% on wet weight) to achieve a viscosity profile of 800–1200 mPa·s at 100 s⁻¹ shear rate, maintaining transfer stability on the gravure cylinder. The rapid fiber-tear bond developed within 0.4 seconds of nip contact is attributed to the instantaneous water drainage into the paper substrate, driven by the capillary network of the fiber mat, which collapses the VAE particles into a coherent adhesive film at a critical solids volume fraction of approximately 0.64. The adhesive must meet indirect food contact requirements under 21 CFR 175.105 for dry food packaging and demonstrate specific migration limits for vinyl acetate monomer below 12 mg/kg food simulant in 10% ethanol at 40°C for 10 days. End laminated structures include folding carton stock for luxury perfumes with a PE-coated aluminum barrier layer, spiral-wound composite canisters for dried milk powder incorporating an EVOH oxygen barrier, and medical tray lid stock requiring lidding peel values of 3.0–5.0 N/15mm on uncoated polyester film per ASTM F904.

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    Certification & Compliance
    More Introduction

    Aqueous vinyl acetate-ethylene (VAE) copolymer dispersions occupy a critical niche between poly(vinyl acetate) homopolymer emulsions and acrylic-based binders, delivering a balance of permanent tack, alkaline hydrolysis resistance, and elongation at sub-zero temperatures unattainable with either alternative. The product designated BJ-806H is a carboxylated, high-ethylene-content VAE emulsion stabilized with a poly(vinyl alcohol) protective colloid system, designed for applications requiring strong wet adhesion to porous cellulosic substrates and resistance to plasticizer migration. Typical unplasticized films exhibit a glass transition temperature of −18 °C by differential scanning calorimetry (DSC) at a heating rate of 10 K/min, with a minimum film-forming temperature (MFFT) below 0 °C per ISO 2115. Solids content is controlled at 54.5 ± 0.5 wt% (ISO 3251), pH 4.5–5.5, and Brookfield viscosity at 23 °C (spindle 3, 20 rpm) ranges from 1 200 mPa·s to 2 400 mPa·s. The dispersion is surfactant-stabilized with an anionic emulsifier package that promotes high-shear colloidal stability during roller-coater application without excessive foaming.

    Specification testing per GB/T 11175-2021 for synthetic resin emulsions requires that the residue on a 40 µm filter screen remain below 0.01 wt% after mechanical stressing for 10 min at 1 800 min⁻¹. Lot-to-lot variability in particle-size distribution, determined by dynamic light scattering, exhibits a Z-average diameter between 0.8 µm and 1.5 µm. Free monomer content is reduced to < 500 ppm for vinyl acetate and < 50 ppm for ethylene through post-polymerization stripping, enabling compliance with indoor air-quality guidelines under AgBB testing schemes and EMICODE EC1 Plus criteria for very-low-emission flooring adhesives.

    Comparing Internal Plasticization Mechanisms in VAE and Acrylic Binders

    Unlike externally plasticized poly(vinyl acetate) adhesives, which suffer from gradual embrittlement as dibutyl phthalate or benzoate plasticizers migrate into adjacent materials, BJ-806H achieves permanent flexibility through internal copolymerization with 15–20 wt% ethylene. Accelerated aging tests at 70 °C under 50% RH for 28 d show that lap-shear adhesion to beechwood retains 93% of its initial value, whereas a conventional PVAc homopolymer with 10 wt% dibutyl phthalate loses 47% of bond strength over the same period, as measured by EN 205. This difference becomes operationally significant in laminated furniture components exposed to underfloor heating, where interfacial temperatures may exceed 40 °C for prolonged periods. Published data for this specific configuration is limited to internal quality-control records; however, the trend aligns with the known diffusion coefficient of phthalate esters in semicrystalline PVAc matrices.

    When BJ-806H is substituted for acrylic emulsions in paper-to-paper laminating, the VAE’s carboxyl functionality interacts with hydrated cellulose fibrils, generating a peel-strength profile that increases over the first 24 h as water migrates from the adhesive layer. In contrast, self-crosslinking acrylic dispersions often achieve maximum strength within 4 h but exhibit a sharper decline in adhesion when exposed to 90% RH and 38 °C for 7 d — a condition specified in ASTM D904 for testing adhesive joints under high humidity. The VAE film’s lower oxygen permeability (120 cm³·mm/m²·d·atm at 23 °C, 50% RH) compared with typical acrylics also reduces oxidative embrittlement in aluminum-foil-to-paper laminates used for aseptic packaging.

    How Does BJ-806H Perform in Silane-Modified Parquet Adhesives?

    In moisture-curing hybrid parquet adhesives where the polymer dispersion is blended with silane-terminated polyether prepolymers, the alkaline hydrolysis resistance of the VAE binder becomes critical. The protective colloid system of BJ-806H withstands the pH 10–11 environment generated by aminopropyltriethoxysilane additives far better than dextrin-stabilized PVAc grades, which undergo chain scission within 48 h of catalysed silanol condensation. A twin-screw mixing unit with an L/D ratio 40 and segmented kneading blocks is required to uniformly distribute the prepolymer into the VAE phase without inducing premature coagulation; typical processing windows demand a stock temperature of 28–32 °C at the die. Above 35 °C, ethylene-rich domains within the latex particles soften sufficiently to coalesce inside the barrel, leading to torque spikes and shutdowns. In-plant data from a continuous line manufacturing 800 kg/h of silane-modified wood-flooring adhesive indicates that switching from a standard Tg = 0 °C VAE to BJ-806H eliminated visible gel particles in a 125 µm drawdown film after 6 months of ambient storage.

    Open time on a porous concrete screed conditioned to 4% moisture content by calcium carbide method (ASTM D4944) extends to 28 min at 23 °C and 65% RH when the blend contains 60 pbw of BJ-806H per 100 pbw of total binder. This exceeds the 20 min typically recorded for a PVAc homopolymer of equivalent solids under identical conditions, allowing the installer sufficient repositioning time for engineered panels exceeding 2.4 m in length.

    Key Property Comparison — BJ-806H vs. Standard D3 PVAc vs. Acrylic Dispersion
    PropertyBJ-806H VAEPVAc Homo-D3Acrylic (Tg −10 °C)
    MFFT (°C, ISO 2115)< 0+4 (plasticized)+5
    Heat resistance after 7 d (WATT 91)6.2 N/mm²3.1 N/mm²5.8 N/mm²
    Peel adhesion to PVC (N/25 mm, EN 1372)12.42.1 (plasticizer migration)8.9
    Alkali gel time (1N NaOH, 50 °C)> 96 h< 8 h> 120 h
    Formaldehyde contentNot detectedPossible (0.02% max)Not detected

    Critical Processing Constraints During High-Shear Application

    When BJ-806H is pumped through an airless spray system operating at 120 bar fluid pressure with a 0.33 mm tungsten-carbide tip, shear rates at the orifice approach 10⁵ s⁻¹. Under these conditions, the protective colloid layer around individual latex particles experiences transient disruption, and the probability of shear-induced coagulation rises sharply if the anionic surfactant concentration in the serum phase falls below a critical micelle threshold. Manufacturers of spray-applied carpet-backing adhesives must therefore maintain the total solids of the compounded mix within 52–55% and avoid dilution with hard water (conductivity > 500 µS/cm), which compresses the electrical double layer. A feed pump equipped with a pneumatically driven double-diaphragm unit, rather than a progressing-cavity pump, minimizes pulsation and reduces the residence time of the emulsion in zones of localized shear heating. Failure to adhere to these parameters results in nozzle blockages after 45–60 min of continuous operation, as documented on a 500 L batch scale serving a tufted-carpet secondary-backing line.

    The viscosity response of BJ-806H to neutralization with ammonia or sodium hydroxide follows a pseudoplastic rheological profile, with a power-law index n of approximately 0.6 at pH 6.8. This shear-thinning behavior is advantageous for roller-coater application onto porous substrates such as medium-density fiberboard, where the low-shear viscosity (15 000 mPa·s at 1 s⁻¹) prevents excessive penetration into the board, while the high-shear viscosity (800 mPa·s at 1 000 s⁻¹) permits smooth transfer with a trihelical gravure cylinder engraved at 50 lines/cm.

    When BJ-806H Replaces Styrene-Acrylic Binders in Cementitious Waterproofing Slurries

    Two-component cementitious waterproofing slurries formulated with styrene-acrylic emulsions often exhibit a reduction in flexural strength after 28 d of water immersion at 23 °C, attributed to saponification of acrylate ester side chains in the alkaline pore solution (pH > 13). Substituting the polymer binder with BJ-806H at a polymer-to-cement ratio (p/c) of 0.30 shifts the dominant degradation pathway from chemical hydrolysis to physical swelling, which is largely reversible upon drying. Adhesion to damp concrete prisms tested per GB/T 23445-2009 yields a pull-off strength of 1.8 MPa after 7 d dry plus 7 d in water, exceeding the 1.0 MPa threshold stipulated for Type II products. The minimum usage temperature is constrained: emulsion stability is compromised when the slurry is applied at substrate temperatures below +3 °C, because incipient ice crystal formation ruptures the latex particles before cement hydration generates sufficient exothermic heat to raise the film temperature above 0 °C. A practical workaround employed on construction sites in northern latitudes involves preheating the liquid component to 15–20 °C and replacing part of the gauging water with a 5% calcium chloride accelerator solution, though this approach must be validated for each specific cement type to avoid flash setting.

    Below-grade applications in contact with sulfate-bearing groundwater (sulfate concentration > 600 mg/L) require the use of sulfate-resisting cement conforming to GB 175-2007 Type P·HSR alongside BJ-806H. The ethylene comonomer in the polymer backbone does not introduce ester groups susceptible to sulfate attack, unlike some cellulose-ether rheology modifiers that degrade within 90 d under the same conditions, leading to slump loss and patch debonding.

    Differences between BJ-806H and its lower-ethylene analogue BJ-805 become most evident under dynamic loading. The latter, with a Tg of +5 °C and ethylene content below 10%, develops microcracks in a 2 mm-thick polymer-cement coating applied to an exterior insulation finishing system (EIFS) after 500 freeze-thaw cycles (−20 °C/+20 °C, 24 h per cycle) per ETAG 004 Section 5.3.1.2. BJ-806H, by contrast, exhibits crack-bridging capability up to 0.4 mm at −10 °C as determined by EN 1062-7, a property attributed to the low-temperature segmental mobility of the ethylene-rich amorphous phase.

    Regulatory and Compliance Framework — BJ-806H
    Standard / RegulationScopeTypical Pass Criteria
    FDA 21 CFR 175.105Adhesives for indirect food contactComponent migration < food-type limits
    REACH (EC) 1907/2006Registration of monomer residuesSVHC < 0.1 wt%
    GB 18583-2008Indoor decorating and refurbishing materials — limit of harmful substancesVOC < 30 g/L; free formaldehyde not detected
    RoHS 2011/65/EURestriction of hazardous substances in electrical substratesPb, Hg, Cd, Cr6+ each < 100 ppm
    EN 13986:2004+A1:2015Wood-based panels for construction — formaldehyde class E1E1 emission level with suitable scavenger
    DIBt ZulassungsgrundsätzeGerman approval principles for adhesives for load-bearing timber componentsDelamination resistance after delamination test

    Accelerated Humidity Resistance and Equipment-Specific Observations

    On a high-speed laminating line processing 12 000 m²/d of printed décor paper to particleboard, the use of BJ-806H in a urea-catalyzed crosslinking system required precise control of the chrome-plated application roller temperature: a setpoint of 22 ± 1 °C maintained by circulating chilled water through an internal double-wall design. At roller surface temperatures exceeding 25 °C, partial skinning of the VAE film occurred within the 2.3 s gap between the doctor-blade metering station and the nip, resulting in transfer defects visible as mottled patterns under a 45° angle of incidence. Reducing the line speed from 25 m/min to 22 m/min, coupled with an increase in the relative humidity of the conditioning zone immediately downstream to 85% RH, restored defect-free transfer by maintaining a sufficient partial pressure gradient for water evaporation retardation. This operational boundary was established through a factorial design experiment involving 72 production runs and confirmed that the BJ-806H formulation, unlike a surfactant-stabilized acrylic of equivalent solids, is less forgiving of abrupt dehydration at the interface due to the poly(vinyl alcohol) skin-formation kinetics.

    In a separate application involving wet-lamination of printed PET film to MDF panels, a polyfunctional aziridine crosslinker was post-added at 0.8 wt% of wet emulsion. The pot life of the compounded mixture at 23 °C was 4.5 h, measured to a viscosity doubling point under steady shear at 10 s⁻¹. Beyond this window, the loss modulus G″ steeply increased, attributable to premature interparticle crosslinking that rendered the emulsion unsuitable for gravure application. Plant personnel employed a viscometer-controlled dosing pump with automatic cut-off at 3 000 mPa·s, reducing batch disposal rates by 60% compared to time-based discarding protocols.

    When comparing BJ-806H with a vinyl acetate-versatic acid ester copolymer (VeoVa™ 10) dispersion of equivalent Tg, the principal distinction lies in the cohesive strength development under cyclic wet-dry exposure. After 12 cycles of 24 h water immersion at 40 °C followed by 24 h drying at 23 °C and 30% RH, the VAE-based wood adhesive retained 4.7 N/mm² tensile shear strength on beech per EN 205, whereas the VeoVa system declined to 3.2 N/mm². The difference is attributed to the hydrophobic versatate ester steric shielding limiting co-monomer sequence randomness, creating regions of hydrolytically vulnerable PVAc blocks. The higher sequential randomness distribution of ethylene in BJ-806H, approximated by a Fineman-Ross copolymerization model, results in a more uniform distribution of sterically protective ethylene units along the backbone, preserving ester linkage integrity.