| HS Code | 669626 |
| Product Name | ELVANOL 80-18 |
| Chemical Name | Poly(vinyl alcohol) |
| Appearance | White granular powder |
| Degree Of Hydrolysis | 80-82.7 mol% |
| Viscosity | 18 mPa·s (4% solution at 20°C) |
| Ph | 5.0-7.0 (4% solution) |
| Ash Content | <= 1.0% |
| Volatile Matter | <= 5.0% |
| Bulk Density | 0.5-0.7 g/cm³ |
| Specific Gravity | 1.30 at 25°C |
| Melting Point | ~200°C |
| Glass Transition Temperature | ~40°C |
| Solubility | Soluble in hot water; insoluble in organic solvents |
As an accredited ELVANOL 80-18 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | ELVANOL 80-18 polyvinyl alcohol is supplied as a free-flowing powder in 50 lb (22.7 kg) multi-wall paper bags. |
| Container Loading (20′ FCL) | ELVANOL 80-18 in 20′ FCL: palletized bags, secured, kept dry and ventilated, moisture-protected, proper lashing; no hazardous segregation required. |
| Shipping | ELVANOL 80-18 is a polyvinyl alcohol resin supplied as white granular powder. Ship as non-hazardous, dry cargo in sealed multiwall bags or supersacks. Protect from moisture, humidity, and direct contact with water during transit. Keep away from oxidizing agents and store in a cool, dry area with adequate ventilation. |
| Storage | Store ELVANOL 80-18 in its original, tightly sealed container in a cool, dry, well-ventilated area away from direct sunlight, moisture, and incompatible materials such as strong oxidizers. Protect from physical damage and dust accumulation. Keep containers closed when not in use and rotate stock to avoid prolonged storage. |
| Shelf Life | Shelf life is typically 2 years from manufacture date when stored unopened in a cool, dry area. |
ELVANOL 80-18 is introduced at the size press as a 4–8% aqueous solution prepared in an atmospheric or jet cooker. The grade’s 4% aqueous viscosity of 16.0–20.0 mPa·s at 20 °C, measured by Brookfield rotation in accordance with ASTM D2196-20, permits stable puddle or metering-film transfer when mixed with oxidised starch. For recycled containerboard, a starting blend of 1 part PVOH solids to 4 parts oxidised starch solids at 6.0–8.0% total solids is circulated at 55–65 °C through a pond-type size press; for fine paper using a rod-metered or blade-metered film press, the PVOH fraction is often raised to 2–3 parts per 4 parts starch. The fully hydrolysed 98.0–98.8 mol% structure reduces thermoplasticity and re-wetting on subsequent corrugator heating, while maintaining fibre-to-fibre bond contribution measured by Scott bond TAPPI T569 or tensile energy absorption. Surface strength is typically assessed by IGT pick test ISO 3783:2014; oil- and water-holdout is monitored by Hercules Size Test TAPPI T530 at 60% reflectance. Mills operating closed water loops should control size press pH between 6.5 and 7.5, because residual alum below pH 5.0 can precipitate PVOH and increase cleaned-up blade wear. External size press additions of 1.5–4.0 kg PVOH per dry metric tonne are common when replacing a fraction of starch in high-performance liner and white-top grades. Because ELVANOL 80-18 is fully hydrolysed, dissolution requires 30–45 min at 90–95 °C under low shear; undissolved microgel particles from short cook cycles cause coating streaks and lower opacity in subsequent flexo printing.
| Application area | Representative test standard | Reported parameter |
|---|---|---|
| Paper surface sizing | TAPPI T530, ISO 3783:2014, TAPPI T569 | Hercules size, surface pick, Scott bond |
| Textile warp sizing | ISO 13934-1:2013 | Film tensile strength, elongation at break |
| Ceramic green-body binding | ASTM C1161-18 | Three-point flexural strength |
| Remoistenable adhesive | ASTM D1876-08, TAPPI T477 | T-peel adhesion, block resistance |
| Unit-dose film | ISO 527-3:2018 | Tensile strength, elongation at break |
| Protective colloid in emulsion | ISO 2555:2018 | Brookfield dispersion viscosity |
Prepared as a jet-cooked size liquor at 8.0–12.0% solids for cotton and cotton-rich warp yarns, ELVANOL 80-18 is blended with thinned starch or polyacrylic acid size at a PVOH solids ratio of 20–40% depending on loom type and yarn count. The medium-viscosity profile maintains a size-box viscosity of 40–120 mPa·s at 85 °C, allowing wet pick-up between 8% and 12% on ring-spun Ne 20–40 yarns. Warp abrasion resistance is measured with a Zweigle G552 abrasion tester or by DSM cycling to failure; sizing efficiency is indirectly evaluated by loom stop rate per 100,000 picks. The fully hydrolysed grade gives tensile strength and elongation responses consistent with ISO 13934-1:2013 when cast as an unsupported film; a typical conditioned film exhibits tensile strength of 40–60 MPa and elongation at break of 150–250% after conditioning at 23 °C and 50% RH. Because ELVANOL 80-18 is not cold-water soluble, desizing of pure PVOH size is performed with 80–90 °C water containing 0.5–1.0 g/L nonionic wetting agent; starch-sized blends are desized with commercial α-amylase at pH 6.5–7.0 and 70–75 °C before hot wash. Residual PVOH on finished fabric is detected by iodine staining in accordance with internal mill methods; a blue complex persists above approximately 0.1% surface add-on. High-humidity weaving rooms benefit from the grade’s low equilibrium moisture sensitivity relative to starch-only size films, but size-shedding can increase when the size film is overdried below 5% moisture. Addition of 5–10 parts glycerol or polyethylene glycol 400 per 100 parts PVOH resin reduces brittleness for high-twist yarns, though excessive plasticiser lowers size film cohesion and raises warp breakage on air-jet looms.
In tape-casting and dry-pressing operations for technical ceramics, ELVANOL 80-18 functions as a temporary organic binder at 2.0–6.0 wt% of dry ceramic powder. The fully hydrolysed backbone provides higher green tensile strength than partially hydrolysed grades at equivalent binder loading, but it also raises slip viscosity, which is controlled by maintaining the aqueous slurry at 45–55 °C during tape casting. For a 40 vol% alumina slip containing 3.0 wt% ELVANOL 80-18 and 0.5 wt% ammonium polyacrylate dispersant, typical Brookfield viscosity at 20 rpm falls between 3000 and 8000 mPa·s, measured with spindle 4; this range supports doctor-blade gap settings of 0.5–1.5 mm on a continuous tape caster. Green sheet strength is evaluated by three-point flexure using ASTM C1161-18 for advanced ceramics or equivalent in-house bar tests; values are reported on ready-to-sinter tape after drying at 60 °C for 20–30 min to a residual moisture content below 0.5%. Binder burnout is designed around thermogravimetric analysis at 5 °C/min heating rate; ELVANOL 80-18 decomposes predominantly between 250 °C and 480 °C in air, with total ash contribution below 0.5% of ceramic mass when the grade meets standard ash specifications. Sintering profiles for alumina substrates typically include a 60–120 min hold at 450–500 °C before ramp to 1500 °C, preventing carbon residue and through-thickness delamination. The addition of 10–30 parts glycerol per 100 parts PVOH solids plasticises the binder film and lowers the glass transition of the dried matrix, but excessive glycerol delays burnout and can produce pinholes in tape-cast layers above 100 µm dry thickness. Published data for this specific configuration is limited at high tape thicknesses; operators commonly adjust plasticiser ratio by iterative green density measurements rather than relying on fixed nominal values.
A remoistenable seam adhesive based on ELVANOL 80-18 is formulated by dissolving 15–20 parts resin in 80–85 parts water at 90–95 °C, then adding 3–5 parts glycerol or sorbitol as humectant and 0.5–1.0 part defoamer. The resulting adhesive is applied by wheel or nozzle at 10–20 g/m² dry coat weight onto paper envelopes, paper tape, or label stock; drying is performed on a steam-heated drum at 90–110 °C for 5–15 s. The fully hydrolysed grade yields a non-tacky film at 23 °C and 50% RH, which is evaluated by block resistance test TAPPI T477 or an inclined-plane tack method; adhesion is reactivated by passing the coated side over a water wheel or sponge with 0.2–0.5 g/m² moisture. T-peel adhesion to recycled paper and kraft paper is measured according to ASTM D1876-08 with a crosshead speed of 300 mm/min; typical remoistening peel values fall between 1.0 and 3.0 N/mm on 80 g/m² kraft. Borax is sometimes added at 0.1–0.3 wt% of wet adhesive to increase tack wet-out and shift rheology through didiol complexation, but borax levels above 0.5 wt% cause gelation and irreversible viscosity build in fully hydrolysed PVOH. The 98.0–98.8 mol% hydrolysis degree reduces cold-water tack development relative to 88 mol% grades, making ELVANOL 80-18 suitable for applications requiring moisture-resistant dry film but rapid bonding after remoistening. Because the grade’s 4% viscosity of 16.0–20.0 mPa·s is higher than low-viscosity remoistening grades, transfer-coating head pressure should be maintained above 1.5 bar for engraved roller coaters; lower pressure causes skips on highly calendered substrates.
The conversion of ELVANOL 80-18 into cast film for agrochemical unit-dose packaging follows a solution-casting or tape-casting sequence rather than blown extrusion, because dry granules must be first dissolved at 90–95 °C for 45–60 min to form a 10–15 wt% dope. Plasticiser content is normally 15–25 parts per 100 parts PVOH solids, with glycerol or trimethylolpropane selected to meet cold-water disintegration targets. Wet film is cast at 300–800 µm onto a polyester carrier and dried at 70–95 °C to a residual moisture content of 8–12%; final film thickness is controlled between 35 and 75 µm. Mechanical performance is measured according to ISO 527-3:2018 for plastics film; typical unsupported film values for ELVANOL 80-18 with 20 phr glycerol are tensile strength 35–55 MPa and elongation at break 150–350% after conditioning at 23 °C and 50% RH, but published data for this specific configuration is limited and producer trials should verify. Disintegration time in water at 10 °C, 20 °C, and 30 °C is assessed by a 1 L stirred beaker method using a 50 mm × 50 mm film swatch. Fully hydrolysed 98 mol% grade requires warm water for rapid dissolution, so agrochemical packages designed for cold-water release below 15 °C often blend ELVANOL 80-18 with 10–30 wt% of an 88 mol% grade. Contact with strong oxidising agents, high-pH alkaline formulations above pH 9, or borate-containing tank-mix adjuvants can produce gelation or accelerated hydrolysis; compatibility tests after 7-day accelerated ageing at 40 °C and 75% RH are therefore required before approving a formulation. Sealing of water-soluble film pouches is performed by heat sealing at 120–150 °C, 0.2–0.5 s dwell time, 2–4 bar jaw pressure; excessive sealing temperature above the crystalline melt range reduces toughness at the seal edge and promotes pinholes.
In vinyl acetate emulsion polymerisation, ELVANOL 80-18 is employed as a high-molecular-weight protective colloid at 2.0–5.0 wt% of the aqueous phase. The hydrolysis degree of 98.0–98.8 mol% produces a lower cloud point and less blocky branching than partially hydrolysed grades, yielding polyvinyl acetate dispersions with medium to high Brookfield viscosity and strong shear stability. Batch or semi-batch reactor charging is performed by pre-dissolving the resin at 90 °C for 30–60 min, cooling to reaction temperature of 60–70 °C, and adding as a 10% stock solution; initiator is typically hydrogen peroxide/tartaric acid or persulphate redox at 0.05–0.2 wt% of monomer. Particle size distributions measured by laser diffraction typically shift to smaller volume mean diameters when PVOH concentration increases from 2.0 to 5.0 wt%; residual PVOH on particle surfaces contributes to wet-tack and water resistance trade-offs. The resulting dispersion is characterised by viscosity per ISO 2555:2018 at 23 °C, pH, and lump content after 100 µm filtration; coagulum is weighed after reactor discharge and after 30 min of mechanical shear at 5000 rpm in a laboratory dissolver. Fully hydrolysed grades such as ELVANOL 80-18 can gel at lower temperatures and are less tolerant of methanol-rich feeds than 88 mol% grades; therefore feed systems using methanol/water mixtures above 15 wt% methanol should be avoided unless compatibility testing confirms stability. The high molecular weight of the grade also increases particle bridging and may require a delayed addition profile to avoid thickening before monomer conversion reaches 90%. End-use adhesives based on these dispersions are tested for wet strength and water resistance under DIN EN 204 classifications D1–D4; limit values depend on formulation, not on PVOH alone.
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ELVANOL 80-18 is a high-viscosity, fully hydrolysed polyvinyl alcohol resin supplied in granular form. The product is manufactured by the methanolysis of polyvinyl acetate; residual acetate content is controlled below 2 mol%, and the grade designation encodes a nominal viscosity of 80 mPa·s for a 4 wt% aqueous solution at 20°C according to standard solution viscometry practice. The resin is water-insoluble at ambient temperature and requires heating above approximately 85°C for complete solvation. Dried aqueous solutions form clear, continuous, tough films. The grade is specified for emulsion polymerisation protective colloid systems, paper surface sizing, textile warp sizing, water-resistant adhesives, and barrier film intermediates where high molecular weight and low residual acetate content are required.
The producer’s suffix structure separates viscosity class from hydrolysis class. The first segment, 80, indicates the nominal solution viscosity of the standard 4 wt% aqueous test solution; the second segment, 18, identifies the fully hydrolysed segment, with saponification degree not lower than 99.0 mol% in certificate-of-analysis practice. By comparison, lower-viscosity fully hydrolysed grades with nominal 30 mPa·s solution viscosity are selected where pumping, filtration, and coating-speed constraints impose a lower viscosity ceiling. Partially hydrolysed grades in the 87–89 mol% range dissolve at lower temperatures and show greater cold-water sensitivity, but they also generate more foam, produce weaker wet films, and redisperse more readily after drying. The following class-level comparison is not a substitute for lot-specific certificate values.
| Parameter | ELVANOL 80-18 class | Lower-viscosity fully hydrolysed class | Partially hydrolysed class |
|---|---|---|---|
| Nominal 4% aqueous viscosity at 20°C | 80 mPa·s | 25–35 mPa·s | 20–30 mPa·s |
| Degree of hydrolysis | ≥99.0 mol% | ≥99.0 mol% | 87–89 mol% |
| Cold-water solubility at 20°C | negligible | negligible | partial |
| Typical film tensile strength per ASTM D882 | 50–70 MPa | 40–55 MPa | 30–45 MPa |
| Oxygen transmission in dry film per ASTM D3985 | <0.1 cm³·mm/(m²·day·atm) | <0.1 cm³·mm/(m²·day·atm) | <0.3 cm³·mm/(m²·day·atm) |
| Minimum complete dissolution temperature | 85–96°C | 80–95°C | 60–80°C |
On a production line, solution preparation departs from laboratory practice. Dry granules are first dispersed into cold water at 20–25°C under agitation; charging powder directly into hot water produces gel particles and fisheyes that are difficult to disperse downstream. The slurry is then heated by direct steam injection to 92–96°C and held for 45–60 min. At 10–12 wt% solids, the solution is strongly shear-thinning and may exceed 1,000–3,000 mPa·s at process temperature, depending on viscometer shear rate. Transfer pumps, filters, and coating lines are sized for this non-Newtonian response; positive-displacement pumps are preferred over centrifugal pumps for solids above 12 wt%.
The limiting unit operation in high-viscosity fully hydrolysed PVOH use is frequently heat transfer rather than dissolution kinetics. Jacketed make-down tanks without direct steam may require 90 min or longer to reach complete solvation. Direct steam eductors operating at 0.6–0.8 MPa steam pressure reduce heat-up to approximately 40–50 min, but steam condensate dilutes the batch and must be included in the water charge calculation. High-shear rotor-stator mixers can lower fisheye counts at the dispersion stage; however, prolonged high shear after dissolution generates frictional heat and may shear-degrade the polymer. Agitation is therefore reduced after the 85°C temperature threshold is crossed.
The solutions are incompatible with borate ions, concentrated sodium sulfate, and several multivalent metal salts. These species cause gelation or precipitation. Storage tanks and coating lines previously used for starch or borate-containing sizing must be flushed with hot water to prevent deposits in screens and doctor blades. Open tanks allow skin formation at concentrations above 12 wt%; closed or covered tanks with controlled headspace are used for extended runs. Solutions held above 95°C for more than 60 min may yellow and undergo slight hydrolysis or oxidation, shifting solution pH and reducing viscosity stability.
Cast film performance is strongly influenced by drying rate, conditioning humidity, and residual moisture. Class-level data for fully hydrolysed high-viscosity PVOH show tensile strength of 50–70 MPa and elongation at break of 100–180% when films are dried at 105°C, conditioned at 23°C and 50% RH, and tested according to ASTM D882. The polymer is intrinsically hydrophilic; water vapour transmission measured per ASTM E96/E96M is therefore high, and the material is not specified as a moisture barrier. Dry oxygen transmission per ASTM D3985 is below 0.1 cm³·mm/(m²·day·atm), but this value degrades sharply at elevated relative humidity as sorbed water plasticises the film and increases free volume.
The humidity-dependent barrier boundary is not linear. Between 40% RH and 70% RH, oxygen permeability may rise by one to two orders of magnitude for unplasticised PVOH films. In paper sizing and adhesive applications, this moisture sensitivity is less critical because the polymer functions as a binder and surface-strength additive rather than as a stand-alone barrier. For food packaging structures, ELVANOL 80-18 is typically used as a barrier primer in combination with clay, nanocellulose, or topcoat layers that depress moisture-driven oxygen permeability loss. The exact oxygen transmission of a formulated coating depends on coat weight, coating holdout, and topcoat coverage; published data for this exact grade in high-humidity multilayer structures is limited.
In vinyl acetate and vinyl acetate-ethylene emulsion polymerisation, high-molecular-weight fully hydrolysed PVOH is used as the primary protective colloid when larger particle size, higher emulsion viscosity, and improved mechanical stability are required. The high solution viscosity of ELVANOL 80-18 raises aqueous-phase viscosity at equivalent addition; reactor cooling capacity and monomer mass transfer become limiting earlier than with lower-viscosity grades. Typical protective colloid additions range from 4 wt% to 8 wt% on total monomer. Batch reactors with 30 m³ working volume and anchor/helical impellers show higher torque and reduced circulation at the upper end of that range. The exact particle-size distribution depends on initiator dosing, agitation profile, and comonomer ratio; published data for this specific grade in high-solids vinyl acetate-ethylene systems is limited, and plant trials are required.
Textile warp sizing uses the resin at 6–10 wt% solids in combination with starch or acrylic sizes. The high-viscosity grade improves sized-yarn abrasion resistance, but desizing requires hot water above 85°C with detergent. Paper surface sizing on a size press at 2–6 wt% solids improves wax pick values and recycled linerboard surface strength; the effect depends on size-press pickup and drying profile. Wax pick improvement is assessed by a test such as TAPPI T 459. The high viscosity class reduces misting at high machine speeds but may require reduced solids to maintain target pickup.
The first operational difference is viscosity-related: at equal solids, ELVANOL 80-18 generates higher back-pressure in filters, coating heads, and transfer lines than a lower-viscosity fully hydrolysed grade. The second difference is solubility-related: compared with partially hydrolysed grades, it requires hot-water make-down and shows negligible room-temperature solubility, which reduces re-wettability of the dried film and increases water resistance after application. The third difference is film-strength-related: the high molecular weight produces higher tensile strength and wet tack, but also makes air entrainment, skin formation, and viscosity drift more difficult to manage in open tanks.
For paper and paperboard food-contact applications, regulatory references commonly include 21 CFR 176.170 and 21 CFR 176.180 when the resin is used as a size or coating component. Lot-specific conformity statements and migration limits must be obtained from the supplier. The grade is not recommended for cold-water-dispersible packaging adhesives, for thickening formulations requiring room-temperature dissolution, or for borate-crosslinked systems. Bulk containers should be kept sealed at relative humidity below 60%; absorbed moisture can alter the 4% solution viscosity by several percentage points and reduce the accuracy of gravimetric charging.
