| HS Code | 737242 |
| Appearance | milky white liquid |
| Solid Content Percent | 50-55 |
| Viscosity Mpa S | 5000-15000 |
| Ph | 4.0-6.0 |
| Density G Cm3 | 1.05-1.10 |
| Particle Size Nm | 500-1500 |
| Glass Transition Temperature C | 10-30 |
| Minimum Film Forming Temperature C | 5-15 |
| Tensile Strength Mpa | 5-10 |
| Elongation Percent | 200-500 |
| Adhesion To Wood Mpa | greater_than_2.0 |
| Water Resistance | fair |
| Storage Stability Months | 6-12 |
As an accredited General Purpose PVAc Emulsion factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Supplied in 25 kg polythene-lined drums with secure lids, ensuring safe storage, handling, and minimal spillage. |
| Container Loading (20′ FCL) | General Purpose PVAc Emulsion loaded in 20′ FCL using drums/IBCs, secured properly, protected from freezing and extreme heat. |
| Shipping | General Purpose PVAc Emulsion ships as a non-hazardous aqueous dispersion. Pack in sealed drums or IBCs to prevent spillage and drying. Keep protected from freezing, extreme heat, and direct sunlight during transit. Avoid prolonged storage above recommended temperatures to maintain viscosity and stability. Standard truck freight with dry, ventilated conditions. |
| Storage | Store General Purpose PVAc Emulsion in tightly sealed original containers in a cool, dry, well-ventilated area. Protect from direct sunlight and freezing. Recommended storage temperature is between 5°C and 40°C. Keep away from strong oxidizers and incompatible chemicals. Properly stored, the emulsion typically remains stable for up to 12 months. |
| Shelf Life | Store tightly sealed at 5–35°C, protected from freezing. Shelf life: 12 months from manufacture date. |
General-purpose PVAc homopolymer emulsions are specified in interior wood bonding primarily because their rheological profile permits roll-coat transfer at 2,500–8,000 mPa·s and the resulting dry film exhibits sufficient shear adhesion on porous substrates such as beech, birch, poplar, and laminated veneer lumber. In cold-press furniture core lamination and edge-glued panel production, the adhesive is usually applied as supplied at 50–55% solids, then diluted only with process water to maintain a wet film weight of 60–90 g/m². The starting-point formulation for a gap-filling interior wood adhesive is 100 parts PVAc homopolymer emulsion, 5–12 parts water, 0.5–2.0 parts propylene carbonate or triacetin as plasticizer, 2–5 parts fine calcium carbonate, and 0.2–0.5 parts silicone-free defoamer. Calcium carbonate addition above 8 parts per 100 parts emulsion reduces wet tack on hard maple and often produces a chalky dry film with reduced shear transfer through the bond line.
The compliance position of an unmodified general-purpose PVAc homopolymer is best defined by EN 204 and EN 205. Dry-bond assemblies conditioned at 23 °C and 50% RH for 7 days commonly reach the EN 204 D2 dry-use requirement, but the same unmodified film cannot reliably pass EN 204 D3 wet-cycling thresholds unless a crosslinking organic or inorganic acid system is introduced. Under ASTM D905 compression shear testing, published datasheet values for homopolymer PVAc on hard maple frequently fall between 10 N/mm² and 18 N/mm² in the dry state, while 24 h water immersion values may drop below 2 N/mm². ASTM D5751 is the applicable specification for laminate joints in nonstructural lumber products and is used to generate wet-use data for interior furniture and millwork adhesives where continuous load-bearing performance is not required.
Production-scale bonding at the laminating press is governed by open time, clamp time, and wood moisture. The adhesive is typically transferred by a rotating drum roller coater or ribbed roller at 60–90 g/m² wet weight, followed by a stack assembly window of 5–15 min at 20–25 °C. The hydraulic multi-daylight cold press is then closed at 0.3–0.8 N/mm² for 20–40 min, depending on wood species, adhesive solids, and ambient humidity. Wood moisture must be controlled between 8% and 12% because excessive moisture retards coagulation and delays fibre-tear development at the interface. For high-frequency-assisted presses, clamping time can be reduced to 2–4 min at 27.12 MHz because the polar emulsion responds rapidly to dielectric heating; however, arcing at the bond line is possible if the adhesive contains free water or if the ply layout creates non-uniform field density. Wetted parts on adhesive transfer equipment should be 316 stainless steel or plastic because the emulsion pH of 3.5–5.0 can accelerate mild steel corrosion.
Terminal products from this application segment include edge-glued furniture panels, veneered table tops, lumber-core blanks, interior door stiles and rails, drawer box assembly, and flat-panel veneer lay-up where dry service conditions are specified. Operational boundaries are explicit: the unmodified homopolymer PVAc is limited to EN 204 D2 dry interior service and is not suitable for exterior exposure, for structural load-bearing joints, or for bond lines that will contact liquid water repeatedly. The material also requires frost-free storage above 0 °C because freeze-thaw cycling can irreversibly coagulate the dispersion and create grit particles that disrupt roller coating.
On spiral tube winding lines, adhesive pickup must balance two competing failure modes: excessive viscosity raises winding amperage and causes delamination at the downstream slitting station, while low viscosity produces strike-through and surface blistering on the outer paper ply. The PVAc homopolymer is therefore diluted from its supplied 50–55% solids to a working range of 45–50% solids using 8–15 parts water per 100 parts emulsion. A dextrin solution at 50% solids is commonly compounded at 10–20 parts per 100 parts PVAc to raise wet tack, and the mixed adhesive is held at 1,500–3,500 mPa·s Brookfield RVT, spindle 4, 20 rpm, 25 °C. Defoamer addition of 0.05–0.15 wt% is maintained to prevent foaming in the return pan, which otherwise generates skip lines in the adhesive film.
The downstream process is continuous spiral winding on a stationary polished mandrel with 2–4 paper plies. Adhesive is applied by a ribbed or smooth kiss roller at dry ply pickup of 8–15 g/m² per ply, depending on paper porosity and basis weight. Winding angle is typically set between 45° and 60°, and line speed is held at 25–60 m/min to allow green tack to develop before the tube reaches the cutting station. A pressure roll exerts 0.2–0.4 MPa along the wound ply to consolidate the bond line and expel entrapped air. Mandrel surface temperature is maintained between 40 °C and 60 °C where wall thickness exceeds 3 mm; excessive mandrel heat drives water toward the inner ply and can cause shrink marks or internal diameter expansion after stripping.
Regulatory status for paperboard packaging includes 21 CFR 175.105 for adhesive components used in food packaging when a functional barrier or good manufacturing practice conditions are met. For dry food contact components, converters may also reference 21 CFR 176.170 and 21 CFR 176.180, while the EU framework is Regulation 10/2011 and EC 1935/2004. Physical performance of finished cores is verified under ISO 11093-4 for cylindrical paper cores, with additional internal requirements for winding density and dimensional stability. Terminal products include cores for plastic film, aluminium foil, adhesive tape, textile roll stock, spiral-wound composite can bodies, and fibre drum bodies. The homopolymer PVAc provides dry ply adhesion but is not a moisture-resistant structural adhesive; stock stored above 85% RH can lose edgewise compression strength, and direct water contact will soften the bond line. For paperboard with very high recycled fibre content and high calcium carbonate loading, pickup must be raised toward the upper end of the 8–15 g/m² range because the available absorption capacity for free water is reduced.
Perfect-bound softcover production splits the PVAc adhesive between a low-viscosity spine adhesive and a higher-viscosity side-lap adhesive because the two bond lines experience different shear modes during book opening. The spine formulation is diluted to 45–50% solids and held at 2,500–4,500 mPa·s; the side-lap formulation is applied at 50–55% solids with viscosity controlled at 4,000–8,000 mPa·s. A notched applicator roller deposits the spine adhesive after the book block has been gathered, milled, and notched to expose fibre ends. Machine cover registration is followed by a crimping station that presses the cover onto the side-lap adhesive for 0.5–2.0 s at contact pressures sufficient to spread the wet film without squeezing adhesive into the hinge crease. Cold-set blocks are then held at 20–25 °C for 24 h before three-knife trimming.
The compliance framework for this segment is less defined by a single adhesive test method than by end-use chemical safety requirements. Children’s printed books and paper-based entertainment products may require heavy-metal migration testing under EN 71-3, while the polymer itself is registered and assessed under REACH Regulation (EC) No 1907/2006. For book packaging that also functions as indirect food contact, 21 CFR 175.105 can apply. Published standardized data for adhesive spine pull strength in perfect binding is limited; most converters rely on internal page-pull and flex testing rather than a single EN or ISO method. The operational boundary for general-purpose homopolymer PVAc is its lower pH, often 4.0–5.5, which can contribute to acid migration in archival paper. Converters handling alkaline book paper therefore select buffered PVAc grades adjusted to pH 6.5–7.5 or isolate the adhesive from the text stock. Terminal products include adhesive-bound paperbacks, catalogues, notepads, hardback casing-in, and wallet-style presentation folders. This cold-set adhesive is not suitable for very high-speed binding lines where hot-melt polyurethane or reactive hot-melt spine gluing is required to support cycle rates above 8,000–12,000 books/hour, because the aqueous film requires longer setting time and retained moisture must escape through the paper substrate.
At pigment volume concentrations above 55%, the dry film of a homopolymer PVAc interior flat wall paint becomes discontinuous, and hiding, stain resistance, and wet scrub resistance decline rapidly. Interior flat and ceiling formulations are therefore operated with a PVC between 55% and 75%, but the formulation is not controlled by PVC alone. The particle-size distribution of the emulsion, typically 0.5–2.0 μm, influences coalescent demand and film continuity at the PVC boundary. Binder solids on total wet paint weight are held between 12% and 25%, with coalescing solvent at 2–5% on polymer solids and defoamer at 0.2–0.5% on total batch weight. Increasing coalescent above 5% suppresses early blocking resistance and can reduce package viscosity stability; reducing it below 2% raises the effective minimum film formation temperature and may produce cracking at low indoor application temperatures.
| Formulation parameter | Operating range | Reference method |
|---|---|---|
| Binder solids on total wet paint | 12–25% by weight | ISO 3251 |
| Pigment volume concentration | 55–75% | calculated from oil absorption |
| Coalescent on polymer solids | 2–5% | manufacturer TDS |
| Defoamer on total batch | 0.2–0.5% | no dedicated ASTM method |
| Stormer viscosity | 90–110 KU | ASTM D562 |
| VOC limit, interior matt wall paint | 30 g/L minus water | EU Directive 2004/42/EC, EPA Method 24 |
Manufacturing uses a high-speed disperser with a Cowles blade tip speed between 15 m/s and 20 m/s. Pigment and extender powders, typically rutile titanium dioxide, calcium carbonate, kaolin, and talc, are dispersed in water containing wetting and dispersing agents before the PVAc emulsion is added under low-shear letdown at 400–800 rpm. Cellulose ether or associative thickener is then adjusted to bring the Stormer viscosity to 90–110 KU, and the batch is filtered through a 100–200 μm mesh screen before filling. The terminal product range covers interior flat wall paints, ceiling whites, and primer-sealer systems for porous interior plasterboard and masonry. The compliance anchor is EU Directive 2004/42/EC, which sets a 30 g/L maximum VOC content for water-borne interior matt wall and ceiling paints measured by EPA Method 24 or equivalent. Hiding power is tested under ASTM D2805, viscosity under ASTM D562, and wet scrub resistance under ASTM D2486. This homopolymer PVAc film is not intended for exterior exposure, for wet-climate façade coatings, or for application over fresh cementitious render with pH above 10, because alkaline hydrolysis can progressively soften and etch the binder film. Operational limits also exclude bathroom ceilings with continuous condensation and surfaces requiring burnish-resistant high-scrub ratings above 1000 cycles, where vinyl acetate–ethylene or all-acrylic binders are normally specified.
Ready-mix joint compound formulators specify PVAc homopolymer at low addition levels because the emulsion contributes film elongation that reduces check cracking after forced-air drying, without producing the stiff, brittle network of an all-starch formulation. The wet emulsion is added at 1.5–3.5% on total batch weight, which corresponds to a dry binder contribution of roughly 0.8–2.0% of the dry formulation. Above 4.0 wt% wet addition, the compound becomes excessively plastic and may leave film defects under sanded paint layers; below 1.0 wt%, the dried compound shows higher incidence of hairline cracking when applied at 3 mm thickness and dried at 38 °C and 20% RH. The emulsion is not the primary binder; it works with attapulgite clay, cellulose ether, starch, and calcium carbonate to balance crack resistance, sanding behaviour, and open working time.
Production mixing is carried out in a horizontal shaft mixer with helical or paddle blades at a tip speed of 1.5–3.0 m/s. Dry fillers and rheology modifiers are dispersed first, followed by water and preservative, then the PVAc emulsion is added near the end of the batch to avoid prolonged high-shear exposure. Batch temperature is kept below 40 °C because localized overheating can destabilize the dispersion and form coagulum that will streak the joint finish. Final compound is adjusted to a viscosity of 500–700 Brabender units, a specific gravity of 1.6–1.8, and air content of 2–4%. The governing specification is ASTM C475/C475M for ready-mixed joint compounds, with test procedures under ASTM C474 covering viscosity, shrinkage, putrefaction, and working properties. VOC content is measured by EPA Method 24. Terminal products include ready-mix joint compound, patching compound, skim coat, and texturing compound for gypsum wallboard interiors. The PVAc-containing compound is not a setting-type material; it dries by water evaporation and must not be used as a powder or combined with gypsum accelerators intended for chemical-setting products. Freeze-thaw cycling is an operational boundary: if the packaged compound freezes below 0 °C, the emulsion may coagulate irreversibly and the product should be rejected because remixing will not restore smooth trowel consistency. The compound is also unsuitable for exterior use, for exposure to sustained liquid water, or for filling joints wider than approximately 3 mm without reinforcing tape.
Because dextrin alone lacks dry-film flexibility, high-speed envelope gumming lines compound the PVAc homopolymer with dextrin or polyvinyl alcohol to produce a remoistenable adhesive with stable rewind blocking resistance. The blend is typically 60–75 parts PVAc homopolymer at 50–55% solids, 20–35 parts dextrin solution at 50% solids, and 0.05–0.2 part defoamer. Water is added to reach a total solids range of 45–55% and a coating viscosity of 3,000–8,000 mPa·s. The dextrin phase controls rewetting speed and tack development after water activation, while the PVAc phase provides film continuity and protection against powdering when the dried adhesive line is folded or flexed during envelope production.
Application is carried out on a flexographic or smooth-roll gumming station at 10–20 g/m² dry adhesive weight. The wet film is dried in a forced-air tunnel at 70–100 °C and the paper is rewound at a residual moisture content of 5–8%. Rewetting at the converting stage is performed with unheated water to activate the dried film within 2–10 s; the activated surface then bonds by pressure alone. The regulatory basis includes 21 CFR 175.105 for indirect food-contact packaging where the adhesive is not a direct additive and good manufacturing practice migration limits are respected. EU compliance for paper and board food-contact materials is assessed under EC 1935/2004 and Regulation 10/2011, with specific migration testing applied when the formulation contains dual-use plasticizers or biocides. Children’s stationery and craft envelope applications may additionally require heavy-metal migration testing under EN 71-3. Terminal products include remoistenable envelope flaps, paper labels, trading stamps, collector cards, and wood-free paper tapes. The dried adhesive film is not water-resistant and must not be specified for packaging that will be exposed to liquid water or condensation. Blocking resistance is limited above 70% RH; converters handling coated paper with low absorbency must reduce residual rewound moisture and may require a surface overcoating to prevent adjacent layers from sticking in the rewind roll.
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General Purpose PVAc Emulsion, supplied under model designation GP-PVAc-50, is a high-solids aqueous dispersion of poly(vinyl acetate) homopolymer stabilized with partially hydrolyzed poly(vinyl alcohol). The product falls within the scope of ASTM D4317 for poly(vinyl acetate) emulsion adhesives and is normally supplied as an EN 204 D2-class material for interior non-structural wood assembly. Its principal specification includes solids content of 50 ± 2% by mass per ISO 3251, Brookfield RVT viscosity of 4000–6500 mPa·s at 25 °C and 20 rpm per ISO 2555, pH of 4.0–5.5 per ISO 976, density of 1.08–1.11 g/cm³ per ISO 2811, and minimum film formation temperature of 7–12 °C per ISO 2115. The dry film is clear to slightly hazy and has a glass transition temperature near 30 °C. The dispersion is used in wood gluing, paper lamination, carton sealing, and general assembly of porous substrates where moisture resistance requirements do not exceed interior D2 exposure.
Table 1 — Representative property specification for GP-PVAc-50.
| Property | Test method | Typical value |
|---|---|---|
| Appearance | Visual | White liquid |
| Solids content | ISO 3251 | 50 ± 2% by mass |
| Viscosity, Brookfield RVT, spindle 4, 20 rpm, 25 °C | ISO 2555 | 4000–6500 mPa·s |
| pH | ISO 976 | 4.0–5.5 |
| Density | ISO 2811 | 1.08–1.11 g/cm³ |
| Minimum film formation temperature | ISO 2115 | 7–12 °C |
| Median particle size | ISO 13320-1 | 0.5–1.5 µm |
The poly(vinyl alcohol) protective colloid gives the dispersion its pseudoplastic flow, rapid set on porous substrates, and borax-response profile. Unlike surfactant-stabilized acrylic dispersions, this stabilizer system is not primarily micellar; foam formation in high-speed recirculation loops is therefore controlled more by pump leakage and air entrainment than by surfactant concentration. When foam is generated in closed circulation lines, a mineral oil or silicone defoamer is added at 0.1–0.3% of total dispersion mass; silicone additions above 0.5% can produce surface defects on coated board because the defoamer migrates to the film interface during drying.
The primary differences are mechanical hardness, water resistance, compatibility with low-energy surfaces, and cost. General-purpose PVAc has a homopolymer dry glass transition temperature of 28–35 °C; this yields higher dry shear strength on wood at room temperature but also greater brittleness than ethylene-vinyl acetate dispersions with glass transition temperatures below 0 °C. At fixed film weight on beech conditioned at 23 °C and 50% RH, a PVAc homopolymer bond tested under ASTM D905 can develop shear values in the range of 9–14 N/mm²; published data for this specific commercial formulation is limited. Ethylene-vinyl acetate and vinyl acetate/ethylene grades provide lower modulus films, improved adhesion to some plastics, and better flexibility, but their creep resistance under sustained load is generally lower. Acrylic dispersions can be formulated over a broad glass transition range and provide higher UV and hydrolysis resistance, but their set speed on uncoated kraft is often slower than PVAc and their unit cost is higher. The following table summarizes the principal comparative performance classes.
Table 2 — Comparative performance classes for aqueous adhesive films at similar solids.
| Dispersion class | Typical dry Tg | MFFT | Wet resistance profile | Principal process limitation |
|---|---|---|---|---|
| General-purpose PVAc homopolymer | 28–35 °C | 7–12 °C | Interior D2; wet strength falls after immersion | Thermoplastic creep above 50 °C; pH-sensitive |
| Ethylene-vinyl acetate copolymer | −20 to 0 °C | <0 °C | Improved water resistance; flexible | Lower dry shear on wood; higher film tack |
| Vinyl acetate/ethylene dispersion | −15 to 10 °C | <0 °C | Good adhesion to low-energy substrates | Lower hardness and heat resistance |
| Acrylic dispersion | −40 to 40 °C depending on comonomer | 0–30 °C depending on grade | High hydrolysis and UV resistance | Higher cost; slower paper fibre-tear in early bond development |
| Polyurethane dispersion | −50 to 30 °C | 0–20 °C | High toughness and water resistance | Higher cost; limited open-time windows |
On softwood and hardwood edge-gluing lines using heated press plattens or radio-frequency curing, the adhesive is applied at 120–180 g/m² by multi-roll spreader. Open time is normally 6–10 min at 23 °C and 50% RH; press pressure of 0.4–0.8 N/mm² for softwood and 0.6–1.2 N/mm² for hardwoods is sufficient for panel flattening, while bond line thickness should remain below 0.10 mm to prevent excess shrinkage and solvent entrapment. The pressed assembly reaches handling strength within 30–60 min at room temperature and full strength after 7 days at 23 °C/50% RH. Under the sequential conditioning defined in EN 204 D2, the adhesive must demonstrate dry and wet shear values on a prescribed beech substrate; verification is substrate-specific, and production trials are required for radiata pine, oak, and tannin-rich hardwoods. Multi-opening press operation generally requires substrate moisture content of 8–12%; moisture above 14% increases the frequency of starved joints. The product is not appropriate for bent wood or postforming operations where the thermoplastic film relaxes under sustained bending stress.
At transfer rates used on engraved-roller coaters, the dispersion is pseudoplastic. Brookfield RVT data at 20 rpm and 25 °C alone are not sufficient for line setup; cone-and-plate measurements at 1000 s⁻¹ typically show apparent viscosity of 150–600 mPa·s for the 50% solids grade. This allows doctoring at line speeds of 60–120 m/min; above 120 m/min, roller misting and spatter become process-limiting unless deionized water is added at 2–4 wt%. Wet film thickness should be kept at 20–30 µm for lamination with clay-coated paperboard. Drying tunnel air temperature of 70–85 °C and air velocity of 1.5–2.5 m/s remove water sufficiently for stacking, but full coalescence of the homopolymer at room temperature may require 24–48 h. In production environments above 60% RH, water release is slower, and stacks should be preconditioned at 35–40 °C for 2–4 h before die-cutting or folding. The dispersion is stable under mechanical shear up to 45 °C; prolonged recirculation above 45 °C can create grit from particle aggregation. Borax extenders up to 10 wt% are compatible when added as a 10–15% solution under slow agitation, but pH should not fall below 3.5.
In paper and packaging converting, the dispersion is applied by roller or nozzle at wet coating weights of 10–30 g/m² on clay-coated board, uncoated kraft, and porous paper laminates. Side-seam bonding of folding cartons at line speeds up to 150 m/min is practical when viscosity is 3000–5000 mPa·s and solids are held at 45–50%. Open time on fast-running folds is 5–10 s; slow stationary glue lines expose the film to 3–8 min of open time. Full fibre-tear adhesion on uncoated kraft after 24 h at 23 °C/50% RH is a common production acceptance test, though the failure mode depends on fibre stock and coating structure. Polyethylene-laminated board and UV-cured coatings require surface energy above 38 mN/m determined by ASTM D2578 wetting tension; below this threshold, the dispersion reticulates and fails to wet. Food-contact packages must be evaluated on the finished article because the general-purpose material may contain trace vinyl acetate monomer and processing surfactants; 21 CFR 175.105 and EU Regulation 10/2011 apply to the package, not to the bulk emulsion alone.
General-purpose PVAc homopolymer is not a structural adhesive and is not suitable for continuous water immersion, exterior exposure, or service temperatures above 50 °C under sustained load. It typically meets EN 204 D1 or D2; it does not meet D3 or D4 unless the specific formulation contains an added crosslinker, because the poly(vinyl alcohol) protective colloid swells and the poly(vinyl acetate) ester linkage is hydrolytically sensitive at alkaline pH. Water soak testing under the schedules referenced in EN 204 can reduce wet shear strength to 20–40% of dry value for unprotected homopolymer; published data for this specific grade is limited, and fabricators should verify on the actual assembled panel. For higher moisture resistance, the appropriate substitutions are D3/D4 crosslinking PVAc, vinyl acetate/ethylene copolymer, or dispersion-modified polyurethane. The general-purpose product should not be formulated above pH 8.5, because alkaline hydrolysis releases acetic acid, lowers pH, and destabilizes the dispersion. Oak, radiata pine, and other tannin-rich substrates can produce staining at high moisture levels; trial bonding is required for visual acceptance.
Thermoplastic creep is the critical performance boundary for filled assembly adhesives. In a static load test using a dead-load creep rig at 25% of short-duration shear strength, an unplasticized PVAc bond can show progressive deformation above 35–40 °C because the dry polymer softens as it approaches its glass transition temperature. Plasticized grades deform earlier; this general-purpose dispersion contains no added plasticizer, but residual monomer and protective colloid content influence effective dry film softening. The rate of creep is also dependent on film thickness, with bond lines above 0.15 mm showing greater time-dependent movement than thin films under identical load. In production-scale furniture assembly, this thermal limit is more important than the short-duration shear value and requires that the adhesive joint not be designed as a load-bearing element.
High-shear mixing with fillers and extenders requires defined tip speeds and temperature control. A 50% solids dispersion stirred with a high-speed disperser at 8–12 m/s tip speed for 15–20 min remains stable if tank temperature is kept below 40 °C. Cavitation and local overheating above 45 °C may cause particle aggregation and grit. Borax solution is added at 10–15% concentration under slow agitation to avoid local viscosity spikes; the final rheology depends on the degree of hydrolysis of the poly(vinyl alcohol) stabilizer and the borate ratio. The tolerance is narrower than for many acrylate dispersions, which accept higher shear and broader pH but generally show slower initial paper fibre-tear and lower early tack on uncoated kraft within the first 10 min. Storage in closed stainless steel or polyethylene containers at 5–35 °C is required; freezing or exposure to repeated freeze-thaw cycles coagulates the dispersion.
