| HS Code | 342658 |
| Chemical Name | Partially saponified polyvinyl alcohol |
| Cas Number | 9002-89-5 |
| Appearance | White to pale yellow free-flowing powder |
| Degree Of Saponification | 86.5 - 89.0 mol% |
| Viscosity 4 Aqueous Solution 20 C | 14.0 - 18.0 mPa·s |
| Ph 4 Aqueous Solution | 5.0 - 7.0 |
| Ash Content | ≤ 0.3 wt% |
| Volatile Content | ≤ 5.0 wt% |
| Bulk Density | 0.40 - 0.60 g/cm³ |
| Solubility | Soluble in water |
As an accredited GOHSENOL GM-14L factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | GOHSENOL GM-14L is supplied as a free-flowing powder in 25 kg multi-layer paper bags with an inner polyethylene liner, palletized. |
| Container Loading (20′ FCL) | 20′ FCL loading of GOHSENOL GM-14L: packed on pallets, secured, containerized for safe, dry transport. |
| Shipping | GOHSENOL GM-14L is a polyvinyl alcohol resin shipped as a free-flowing powder. It is non-hazardous for transport, packaged in multi-layer paper bags or flexible containers. Keep dry, avoid moisture and extreme heat, and store in a cool, ventilated area during transit and warehousing. |
| Storage | Store GOHSENOL GM-14L in a cool, dry, well-ventilated area, away from direct sunlight, heat sources, and ignition. Keep the original container tightly sealed when not in use to prevent moisture absorption and contamination. Avoid exposure to high humidity and water. Maintain stable temperatures and comply with local regulations for safe handling and storage. |
| Shelf Life | Shelf life is typically 24 months from manufacture when stored unopened in a cool, dry place. |
GOHSENOL GM-14L is introduced into vinyl acetate-ethylene emulsion polymerisation as a protective colloid at 4.0–6.0 wt% of total monomer feed. The hydrolysis degree of 86.0–89.0 mol% and viscosity of 20.5–24.5 mPa·s for a 4 wt% aqueous solution at 20 °C place the grade in the partially hydrolysed, medium-viscosity colloid class used to stabilise dispersed polymer particles at pot solids up to 65 wt% without exceeding the reactor agitator torque limit. The colloid solution is prepared in a separate stainless-steel dissolver at 70–80 °C with a high-shear rotor-stator mixer for 45–60 min. Undissolved gel specks are removed through a 180 μm bag filter before the solution is metered into a 10–15 m³ glass-lined pressure reactor. Polymerisation is maintained at 60–80 °C with ethylene partial pressure controlled between 0.8 MPa and 4.0 MPa depending on the target glass transition temperature of the dispersion. Residual vinyl acetate monomer is reduced below 0.5 wt% by post-reaction vacuum stripping at 80–85 °C. Brookfield viscosity measured under ISO 2555 with spindle 4 at 20 rpm and 25 °C typically remains between 5,000 mPa·s and 15,000 mPa·s at this colloid level. Total solids are checked under ISO 3251. Residual monomer is verified under ISO 13741. Food-contact adhesive and coated board applications rely on FDA 21 CFR 175.105 and FDA 21 CFR 176.170; EU industrial hygiene compliance assumes REACH registration and absence of alkylphenol ethoxylates. Production-scale failure modes include seed-latex destabilisation when GM-14L solution is charged faster than 0.4 wt% per minute during the first 30 min of semibatch operation, and upward pH drift above 7.0 when ammonia addition exceeds 0.15 wt%, which accelerates acetate hydrolysis and raises aqueous-phase viscosity. Resulting dispersions are compounded into water-resistant D3 and D4 wood adhesives under EN 204, nonwoven binders, carpet-backing compounds, and paper-to-film laminating adhesives.
For spun polyester and filament polyester warp yarns, GM-14L is batch-mixed with oxidized starch and an acrylic co-binder at a dry solids ratio of 70:30 to 90:10. A production formulation for 167 dtex/48 filament polyester with 12.0 wt% size solids uses 8.5 kg GM-14L, 1.5 kg oxidized corn starch, 0.6 kg polyacrylic acid ester, and 0.2 kg ester-based wax per 100 L deionised water. Cooking in a pressure cooker at 95–98 °C for 90 min is followed by transfer to a size box held at 82–85 °C. In the size box, a production spindle viscometer reading between 160 mPa·s and 220 mPa·s at 85 °C is maintained because film pickup on a 7-cylinder sizing machine becomes nonlinear outside this range. Squeeze roller pressure is set at 180–220 N/cm of roller width to achieve a size add-on of 8–11 wt% on the warp sheet. Warp tensile strength after sizing is evaluated under ASTM D2256-21. Elongation loss must remain below 1.5 percentage points; above this threshold, high-speed rapier loom breakage exceeds 0.8 breaks per 100,000 picks at 500–650 rpm. Desizing efficiency is confirmed by residual starch content below 0.1 wt% using the TEGEWA violet scale, or by weight loss after a 20 min scald at 90 °C with 0.5 g/L nonionic wetting agent. The critical operational limit is size-box viscosity drift. If the circulation loop cools below 78 °C, GM-14L forms a surface skin that deposits on the final drying cylinder and transfers to the woven fabric as brittle specks. Sized warps are converted into woven interlinings, mattress tickings, and high-tenacity polyester workwear fabrics.
In non-aqueous tape casting of 96 wt% alumina substrate, GM-14L is not added directly to the solvent phase. It is first pre-dissolved in deionised water at 15 wt% solids and combined with a plasticiser such as glycerol or triethylene glycol at a 100:20 PVA-to-plasticiser mass ratio before the slurry is let down with ethanol and methyl ethyl ketone. Binder addition on dry ceramic solids is held at 1.5–2.5 wt%. Lower addition produces edge-cracking when a 300 μm doctor blade gap is used at a carrier speed of 0.4–0.8 m/min. At 2.0 wt% binder, green alumina tape dried at 60–70 °C in a two-zone air-float dryer develops tensile strength between 1.0 MPa and 1.5 MPa. Green tape is punched into 100 mm × 100 mm squares and laminated at 70 °C under 25 MPa in a heated platen press. Binder burnout is the process bottleneck. The heating profile must not exceed 1 °C/min to 450 °C with a 2 h hold; faster ramp rates create black-core defects from carbon residues after sintering at 1,600 °C in 95 vol% N₂–5 vol% H₂ atmosphere. A low-ash GM-14L grade is selected because sodium remaining above 0.5 wt% after burnout depresses dielectric strength of alumina substrates. TGA runs are performed under ISO 11358-1:2022 or ASTM E1131-20. Sintered flexural strength is measured under ISO 14704; dielectric breakdown voltage is checked under IEC 60672-3. End products include thick-film circuit substrates, LED chip carriers, and piezoelectric ceramic laminates.
For grease-resistant wrappers and bakery release papers, GM-14L is applied as an aqueous size at 5–8 wt% solids on a film-transfer or pond size press. Replacing oxidized starch at 8 wt% with a GM-14L–carboxymethyl cellulose blend at a dry ratio of 85:15 raises oil resistance from a 3M kit rating of 3 to 7–9 when measured under TAPPI T559 cm-12. Cobb 60 water absorption under ISO 535 remains below 30 g/m² if the base paper is pre-sized with 0.8–1.2 wt% internal alkyl ketene dimer. Surface pH of the size solution is kept between 5.5 and 6.8. Alkaline drift raises the dissolution temperature and produces undissolved microgels that transfer to the paper as lint. At 6 wt% PVA solids and a size-press nip load of 180–220 kN/m, dry pick-up is 0.6–0.9 g/m² per side. Conditioned sheets at 23 °C and 50% RH are tested for folding endurance under TAPPI T511 and surface roughness under ISO 8791-4. The operational boundary is fold-crack sensitivity in converted wrappers. Above 7 wt% PVA solids, crease lines show visible bundle fractures under 180° folding. The size bath is therefore buffered with 0.3 wt% polyethylene glycol 400 as humectant. End products are ovenable paperboard liners, greaseproof bags for takeaway foods, and interleaving papers for pastry manufacturing.
In vinyl chloride suspension polymerisation, GM-14L is used as the secondary dispersant at 0.02–0.04 wt% of vinyl chloride monomer, paired with a primary high-hydrolysis PVA at 0.03–0.05 wt%. The 86.0–89.0 mol% hydrolysis of GM-14L supplies interfacial activity that reduces mean PVC particle size from 130–150 μm to 110–125 μm when the primary-to-secondary mass ratio is shifted from 100:0 to 70:30. The polymerisation is run in a 20 m³ stainless-steel reactor with impeller tip speed of 7.5–9.0 m/s. The GM-14L solution is prepared separately in demineralised water at 20–25 °C; gel lump formation is avoided because the dissolution temperature of the grade at 4 wt% is below 25 °C. Charge water, vinyl chloride, initiator, and both dispersants are homogenised at 10–12 °C before heating to the polymerisation temperature of 57–65 °C. Reactor pressure is sampled every 5 s to control conversion. Suspension PVC resin is assessed by ISO 1628-2 K-value, ISO 60 bulk density, and ISO 4610 plasticizer absorption. Acceptable lot limits for pipe grade are K-value 66–68, bulk density 0.52–0.56 g/cm³, and plasticizer absorption 26–30 g DOP per 100 g resin. Residual vinyl chloride monomer is measured under ISO 6401. A production bottleneck occurs when the secondary dispersant is hydrated at 10 °C or below; gel lumps pass through 250 μm screen packs and create fish-eyes in finished PVC. End products are rigid PVC pressure pipe, cellular foam board, and medical-grade flexible compounds.
GOHSENOL GM-14L is also formulated into remoistenable envelope and label gums at 15–20 wt% solids with 5 wt% dextrin and 0.5 wt% urea on dry adhesive basis; the gum is reverse-roll coated at 60–70 g/m² dry coat weight, dried at 70 °C, and checked for blocking under a 10 kPa load at 40 °C and 50% RH for 24 h.
Competitive GOHSENOL GM-14L 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
Flexible payment, competitive price, premium service - Inquire now!
GOHSENOL GM-14L is a partially saponified polyvinyl alcohol resin supplied as a white to pale-yellow granular powder. Its primary specification differentiators are a 4% aqueous solution viscosity of 16.5–20.0 mPa·s at 20°C measured by Brookfield rotational viscometry in accordance with JIS K6726, a degree of hydrolysis of 86.5–89.0 mol%, a volatile matter content not exceeding 5.0 wt%, an ash content not exceeding 0.2 wt%, and a pH of 5.0–7.0 in a 4 wt% aqueous solution. The grade functions as a protective colloid in aqueous emulsion polymerisation, as a binder in paper surface sizing and textile warp sizing, and as a film-forming component in water-remoistenable adhesives. The material differs from standard GOHSENOL GM-14 principally through its low-ash specification, which reduces residual sodium acetate and thereby reduces ionic interference in pH-sensitive or salt-sensitive latex formulations.
The GM-14L designation places the polymer in the partially saponified class, in which residual acetyl groups disrupt interchain hydrogen bonding and reduce the solution temperature required for complete dissolution. The polymer can be described by the generic polyvinyl alcohol CAS number 9002-89-5. In comparison with fully hydrolysed GOHSENOL GH grades, the residual acetyl content lowers hot-water dissolution temperature and reduces dry-film crystallinity. The low-ash specification is relevant in emulsion systems where sodium ion concentration influences latex stability and in optically inspected films where low haze is a measurable quality parameter. The powder is hygroscopic; bulk handling and meter feeding become progressively more difficult above 60% RH, and the product should be stored in sealed containers at ambient temperature below 40°C.
| Property | Specification or typical range | Test method |
|---|---|---|
| Appearance | White to pale-yellow granular powder | Visual inspection |
| Degree of hydrolysis | 86.5–89.0 mol% | JIS K6726 |
| Viscosity, 4% aqueous at 20°C | 16.5–20.0 mPa·s | Brookfield rotational viscometer, JIS K6726 |
| Volatile matter | ≤5.0 wt% | JIS K6726 |
| Ash content | ≤0.2 wt% | JIS K6726 |
| pH, 4% aqueous solution | 5.0–7.0 | JIS K6726 |
The values in Table 1 are compiled from supplier-published specification sheets and certificates of analysis; batch-specific values may vary. Users should request the current certificate of analysis before releasing bulk material to production.
Incoming quality control for bulk GM-14L should include moisture content by loss on drying at 105°C for 3 h, ash content by ignition at 700–800°C, and Brookfield viscosity of a 4% aqueous solution at 20°C. The viscosity measurement is sensitive to dissolution history; samples should be heated to 80°C for 30 min and cooled to 20°C before testing. A batch with viscosity below the lower specification limit may indicate polymer chain scission during transport or storage, while a batch above the upper limit may indicate incomplete saponification or contamination from a higher-molecular-weight grade. Fluctuations in ash content above 0.2 wt% can be traced to insufficient washing in the manufacturing process and should trigger a supplier nonconformance review.
In a jacketed stainless-steel make-down vessel, GM-14L is dispersed into cold water under agitation before heating to 80–85°C. A pitched-blade impeller or rotor-stator disperser with a tip speed of 3–5 m/s prevents particle agglomeration; direct addition to hot water produces gelatinous lumps that block downstream filters. A stock solution at 10.0 wt% is commonly prepared, but the solution viscosity must be checked at process temperature because final viscosity is a function of concentration, temperature, and residual shear history. Filtration through a 100 μm stainless-steel bag filter after cooling below 40°C removes undissolved particles and protects metering pumps. The solution remains stable under neutral pH conditions, but borate salts create reversible crosslinks that can raise viscosity to gelation. Prolonged exposure to oxidising agents or to pH values below 4.0 or above 9.0 should be avoided because chain scission and acetal formation alter the molecular weight distribution and reduce batch-to-batch repeatability.
A 10.0 wt% stock solution of GM-14L is metered into a baffled production reactor for vinyl acetate and vinyl acetate-ethylene copolymerisation at 1.0–5.0 wt% based on total monomer mass. The protective-colloid mechanism involves grafting of polyvinyl acetate onto the polyvinyl alcohol backbone and adsorption at the latex particle interface. Reactor temperature is held between 60°C and 80°C with a water-soluble initiator such as potassium persulfate or a redox system. Delayed addition of the PVA stock solution reduces initial reaction viscosity and narrows the latex particle size distribution. The low-ash residual profile limits variation in ionic strength, which can otherwise shift the critical coagulation concentration and lead to coagulum accumulation on the reactor wall and baffle surfaces. Final latex viscosity is a practical quality indicator; deviations exceeding ±10% from the established mean are typically investigated through checks of PVA dissolution quality, monomer dosing rate, and residual sodium ion concentration.
On a metered size press or film press, GM-14L is combined with oxidised starch at a size solids content of 2.0–10.0 wt%. The dried film contributes to surface strength as measured by IGT picking resistance in accordance with ISO 3783. The PVA-to-starch ratio is adjusted for base sheet porosity; a higher PVA fraction increases dry film tensile strength but can reduce surface openness and increase curl. During production trials on corrugated medium and linerboard, the low-ash grade reduces deposit formation on size-press rolls relative to standard PVA grades, although published data for this specific configuration is limited and should be verified on the target substrate. Drying capacity is a processing constraint because the aqueous film retains water; the after-dryer section is typically operated to keep the web surface temperature below 110°C to avoid film embrittlement and loss of IGT strength.
The replacement of standard GOHSENOL GM-14 with GM-14L in an existing formulation preserves the viscosity and hydrolysis profile while reducing ash-derived ionic interference. The change is evaluated in emulsion polymerisation and remoistenable adhesive lines where sodium acetate residues contribute to optical haze, humid-ageing adhesion loss, or coagulation during storage. Table 2 summarises the specification shift.
| Property | GOHSENOL GM-14L | GOHSENOL GM-14 |
|---|---|---|
| Degree of hydrolysis | 86.5–89.0 mol% | 86.5–89.0 mol% |
| Viscosity, 4% aqueous at 20°C | 16.5–20.0 mPa·s | 16.5–20.0 mPa·s |
| Ash content | ≤0.2 wt% | ≤0.5 wt% |
| Volatile matter | ≤5.0 wt% | ≤5.0 wt% |
| Main operational variable | Reduced sodium ion interference and lower optical haze | Standard ionic residue |
Across the GOHSENOL range, the GM-14L viscosity class lies between low-viscosity partially saponified GL series grades and high-viscosity fully hydrolysed GH series grades. A lower-viscosity GL grade dissolves more quickly and yields lower solution viscosity at equal solids, but its dried film tensile strength is lower when measured by ASTM D882-18. A fully hydrolysed GH grade provides stronger water resistance after drying and a higher tensile modulus, but it requires a higher dissolution temperature and a longer heat-up cycle. For water-remoistenable adhesives, the partially saponified structure of GM-14L gives faster re-wetting than a fully hydrolysed grade of comparable viscosity; peel adhesion on the target paper stock is quantified with ISO 11339 180° peel testing after conditioning for 24 h at 23°C and 50% RH. Water resistance differences are quantified by water absorption after 24 h immersion in accordance with ASTM D570-22.
In slasher sizing of polyester-cotton warp yarns, GM-14L is applied at 4.0–8.0 wt% solution concentration with a size-box temperature of 50–60°C. Squeeze-roll pressure is set to achieve a dry pick-up of 8.0–14.0 wt% on yarn. The dry film reduces warp hairiness and improves abrasion resistance during weaving; production performance is monitored as warp breaks per 105 weft insertions. The partially saponified grade can be removed by alkaline desizing or enzymatic desizing before dyeing, and residual PVA detection in the desizing wash is used to confirm removal. Compared with a fully hydrolysed grade, desizing of GM-14L is generally faster under equivalent conditions because the desizing liquor penetrates the more amorphous film more readily.
In remoistenable adhesive lines, GM-14L is coated as an aqueous solution and dried to a clear film. The low-ash profile reduces nozzle clogging in slot-die coating equipment and lowers visible haze in the glued flap line. Where wet-strength water resistance is required, GM-14L can be crosslinked with glyoxal or urea-formaldehyde resins; the crosslinking reaction shortens pot life, and gelation time is monitored by Brookfield viscosity over time. Published data for this specific crosslinked configuration is limited because pot life depends on catalyst type, pH, solids content, and storage temperature. Converters should validate adhesion on the target substrate with ISO 11339 and heat-seal re-moistening behaviour on production-speed closure equipment.
Thermal stability of the dry GM-14L powder is relevant in bulk storage and in applications where residual heat history is possible. Polyvinyl alcohol begins to decompose by dehydration and chain scission at elevated temperatures; the exact onset depends on heating rate and atmosphere. Published data for GM-14L-specific thermogravimetric analysis is limited, but supplier certificates of analysis do not include a thermal decomposition specification. For standardised comparison, thermogravimetric analysis under nitrogen at 10°C/min can be used to rank grades. In practice, the product should not be exposed to open heaters, steam tracing above 100°C, or hot hopper dryers for extended periods.
Regulatory compliance for specific end uses is the responsibility of the converter. Polyvinyl alcohol grades of this type are typically evaluated against FDA 21 CFR 176.170 and FDA 21 CFR 176.180 for paper and paperboard intended for food contact, provided migration levels and extraction testing meet the applicable limits. For adhesives and coatings, relevant European Union requirements include Regulation (EC) No 1907/2006 (REACH) and, where electrical and electronic equipment is involved, Directive 2011/65/EU (RoHS). The user should confirm the current supplier regulatory data sheet, because national food-contact certifications and SVHC declarations are region- and substance-volume specific.
