| HS Code | 284300 |
| Product Name | Sinopec VAM LI Low Inhibitor Grade |
| Chemical Name | Vinyl Acetate Monomer |
| Cas Number | 108-05-4 |
| Molecular Formula | C4H6O2 |
| Molecular Weight | 86.09 g/mol |
| Appearance | Clear colorless liquid |
| Purity | ≥ 99.9 wt% |
| Inhibitor Content | 3–7 ppm hydroquinone (HQ) |
| Boiling Point | 72.7 °C at 101.3 kPa |
| Melting Point | -93 °C |
| Flash Point | -8 °C (closed cup) |
| Density | 0.932 g/cm³ at 20 °C |
| Vapor Pressure | 11.7 kPa at 20 °C |
| Solubility In Water | 20 g/L at 20 °C (slightly soluble) |
| Auto Ignition Temperature | 402 °C |
As an accredited Sinopec VAM LI Low Inhibitor Grade factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Supplied in 190 kg steel drums and ISO tank containers, ensuring safe storage and transport of Sinopec VAM LI Low Inhibitor Grade. |
| Container Loading (20′ FCL) | 20' FCL loaded with Sinopec VAM LI Low Inhibitor Grade in sealed ISO tanks or drums, securely lashed, ventilated, and labeled per hazchem regulations. |
| Shipping | Ship as UN 1301 Vinyl acetate, inhibited, Class 3, Packing Group II. Low inhibitor grade requires strict control of inhibitor concentration, dissolved oxygen, and temperature to prevent polymerization. Use grounded, dedicated equipment; avoid heat, sparks, and oxidizers. Emergency response per SDS. |
| Storage | Store in clearly labeled, approved containers under an air atmosphere—never nitrogen blanketing—in a cool, well-ventilated area away from sunlight, heat, and ignition sources. Keep temperatures low (ideally below 15°C) because the low inhibitor content increases polymerization risk. Tightly seal containers, prevent water contamination, use flameproof equipment, and ensure proper grounding. |
| Shelf Life | Shelf life is typically 12 months when stored in sealed original containers under cool, dry, inert conditions. |
Sinopec VAM LI Low Inhibitor Grade is evaluated as a raw monomer stream in continuous solution polymerisation for polyvinyl alcohol. In the PVOH process, vinyl acetate is not a minor additive but the entire carbon backbone source, and the polymerisation loop typically receives a methanol-vinyl acetate feed at 50–80 wt% VAM; the balance is recycled methanol from the saponification and solvent recovery train. Low-inhibitor specification reduces the hydroquinone-type free-radical scavenger concentration, which shortens the induction period and permits a smaller azobisisobutyronitrile or peroxyester initiator injection at 60–70 °C. This is commercially material because excess initiator fragments generate acetaldehyde and methyl acetate side products that must be stripped to meet food-contact requirements. The hydrolysis stage adds sodium hydroxide at 0.02–0.06 mol per acetate equivalent in methanol; controlling local excess at the injection nozzle prevents saponification overshoot, a known cause of resin haze. Compliance for terminal polyvinyl alcohol films and moulding compounds is assessed under FDA 21 CFR 177.1670, EU Regulation 10/2011, and EN 13628-1 headspace migration testing; polyvinyl butyral derived from this PVOH is further qualified for laminated glass under ISO 12543-2 or ANSI/SAE Z26.1, depending on market. Terminal product types include fully hydrolysed PVOH for water-soluble packaging, partially hydrolysed PVOH for textile sizing and paper surface sizing, and PVB interlayer for automotive and architectural laminated glass.
In production-scale continuous trains, the practical boundary of the low-inhibitor feed is that storage prior to the day tank must stay below 25 °C and preferably under a dry air pad rather than prolonged nitrogen blanketing, because oxygen participates with the remaining inhibitor to suppress premature seed formation. Receiving vessels with external recycle cooling and in-line inhibitor monitoring are specified when inventory turnover exceeds 72 h; otherwise the stream should be supplemented with MEHQ or returned to a stabiliser-controlled loop. The downstream stripping column must be operated below 50 kPa absolute to reduce residual vinyl acetate in PVOH below the target of <0.1 wt% in several food-contact applications.
Batch emulsion polymerisation of vinyl acetate homopolymer for waterborne adhesives operates on a different radical-budget principle because the low-inhibitor grade reduces the concentration of MEHQ and hydroquinone species that consume persulfate-derived radicals before nucleation. A plant using a 10,000 L glass-lined reactor with turbine agitation at 3–5 m/s tip speed can reduce the potassium persulfate charge from a standard-stabilised-grade baseline by 10–15% when the incoming monomer inhibitor level is below 3 ppm, provided dissolved oxygen is maintained below 1 ppm. The monomer itself is the sole polymerisable component, so the base formulation records VAM at 100 parts; protective colloid, usually a partially hydrolysed PVOH, is introduced at 4–8 phr; sodium acetate/acetic acid buffer maintains pH 4.5–5.2; and a dibutyl phthalate-free plasticiser may be used only where the adhesive is not intended for food-contact packaging. The final dispersion is concentrated to 50–60% solids with residual monomer below 0.1 wt%. Process control requires a second-stage redox finish using tert-butyl hydroperoxide and sodium metabisulfite to drive conversion above 99.5%. Industry compliance for woodworking adhesives includes EN 204 durability classes D3 and D4, ASTM D5751-99 for non-structural laminate joints, and FDA 21 CFR 175.105 for incidental contact packaging adhesives. Terminal product types are PVAc homopolymer dispersions for furniture assembly, window profile lamination, high-speed packaging, and filter paper bonding.
A recurring production bottleneck with low-inhibitor VAM in PVAc emulsion trains is the onset of fine polymer seeds in the monomer accumulator if the tank is exposed to solar load or if the day tank level is held for more than 48–72 h. These seeds pass through the in-line static mixer and cause screen blockage ahead of the reactor feed pump. The countermeasure is not to re-stabilise with large amine buffers, because amine addition can destabilise the anionic PVAc dispersion; instead, the monomer storage temperature is held below 25 °C, the air pad is monitored, and inhibitory margin is restored with a small MEHQ top-up when the turnover time is extended.
Spray-dried vinyl acetate-ethylene redispersible polymer powder production discharges a different demand set because the polymer emulsion must survive high-pressure ethylene copolymerisation, mechanical filtration, and thermal dehydration without coagulum. In a typical VAE production line, the low-inhibitor VAM is fed as the major hydrophobic/hydrophilic balance monomer at 60–80 wt% of total monomer, with ethylene at 20–40 wt% admitted at 30–80 bar and the reactor controlled at 50–90 °C with a redox initiator system. Reducing the scavenger pool prior to polymerisation decreases the incidence of coarse particles in the latex; this is a field-visible effect on the downstream 150–300 µm bag filter, where standard stabilised VAM lots can generate pressure differentials above 0.8 bar within 8 h, whereas low-inhibitor lots extend filter service. The latex is then compounded with a polyvinyl alcohol protective colloid and atomised through a rotary or nozzle atomiser at 12,000–16,000 rpm, inlet air 140–160 °C, outlet air 65–75 °C, to a moisture content below 2.0 wt%. Anti-caking agents such as kaolin or silica are metered at 5–15 wt% of powder mass to prevent cold flow in bulk bags. In dry-mix construction products, the redispersible polymer powder is added at 2.0–4.5 wt% of total mortar to achieve the required level in cementitious tile adhesives, skim coats, and self-leveling compounds. Compliance is evaluated according to EN 12004-2 or ISO 13007-2 for ceramic tile adhesive tests, EN 998-1 for render and plaster coverage, and EN 1504-3 for concrete repair when polymer-modified mortars are qualified. Terminal products include C2-class tile adhesives, external thermal insulation composite system base coats, cementitious waterproof membranes, and self-leveling underlayments.
| Dry-mix application | RDP addition | VAM in VAE | Key test method | Typical failure mode without low-inhibitor VAM |
|---|---|---|---|---|
| Ceramic tile adhesive | 2.0–4.0 wt% | 70–80 wt% | EN 12004-2 | screen blinding and coagulum specks |
| Self-leveling underlayment | 3.0–5.0 wt% | 60–75 wt% | EN 998-1 | redispersibility loss, surface pitting |
| ETICS basecoat | 2.5–4.5 wt% | 70–80 wt% | EN 998-1 | low water immersion adhesion |
Published data for the interaction between low-inhibitor VAM lot number variation and spray drier fouling is limited, but production audits point to the atomiser wheel as the most sensitive point because any prematurely nucleated seed increases polymer shear sensitivity. Therefore incoming VAM for VAE lines is routinely held under a cold, air-blanketed day tank and tested for induction time before the ethylene override loop is opened. The formulation boundary is that VAM below 60 wt% of monomer demand reduces acetyl group density in the redispersible powder and leads to lower water resistance after wet-cure cycles, whereas VAM above 80 wt% raises glass-transition temperature and can compromise low-temperature film formation in board and tile adhesive formulations.
Solution copolymerization of vinyl chloride and low-inhibitor vinyl acetate is run in ketone or ester solvents at 50–70 °C, with VAM added at 3–15 wt% of the total monomer mass to lower crystallinity and improve solution clarity, dissolution speed, and adhesion to metal and plastic substrates. The low-inhibitor grade reduces carbonyl and colour bodies that otherwise require an additional activated carbon or peroxide finishing step before solvent recovery. The process operates under a reflux-condenser pressure regime, and after conversion reaches 80–90%, the unreacted vinyl chloride is stripped, the resin solution is filtered through 1–10 µm absolute bag filters, and the product is transferred as a 20–35 wt% solids solution. Compliance for this segment focuses on residual vinyl chloride monomer under REACH Annex XVII entries and on printing inks for food-contact packaging under EU Regulation 10/2011 plus Swiss Ordinance 817.023.21; coil coating lines additionally require low yellowing after cure cycles at 180–210 °C. Terminal products include gravure and flexographic inks, heat-seal lacquers, metal coil coatings, and specialty adhesion promoters for calendered PVC. Published data for this specific configuration is limited to supplier-specific solution viscosity curves and chlorinated resin compatibility charts.
For acrylic emulsion architectures used in architectural coatings and engineered textile binders, vinyl acetate is introduced as a random comonomer at 10–25 wt% of the total monomer feed, alongside butyl acrylate, methyl methacrylate, and a small acid monomer. The semibatch seeded process is controlled at 80–85 °C with a pre-emulsion feed over 3–5 h, followed by a redox chase to reduce residual monomer below 0.05 wt% in low-VOC interior products. Low-inhibitor VAM contributes to lower yellowing in the final film because the MEHQ-derived quinone bodies that would otherwise persist through the polymer backbone are reduced; it also decreases coagulum in the reactor discharge filter, a measurable defect that appears as grit in pigment paste. In architectural coatings, the VAM fraction is used to modify film hardness and coalescent demand, with addition below 10 wt% producing limited cost-performance effect and addition above 25 wt% reducing wet scrub resistance under standard tests. Compliance includes ASTM D4946 for scrub resistance, ISO 11998 for wet scrub and cleaning, EU Directive 2004/42/EC for VOC content, and OEKO-TEX Standard 100 when the binder is used in printed textile goods. Terminal product types are interior matt and semi-gloss wall paints, nonwoven wipe binders, pigment printing pastes, and textile backing compounds.
From a processing standpoint, the low-inhibitor VAM fraction in acrylic emulsion is not the determining factor for reactor heat removal; the limiting variable remains the acrylic pre-emulsion feed rate and the jacket heat transfer coefficient. However, when the VAM inventory exceeds 72 h at 25 °C, the downstream feed filter may develop a pressure rise due to oligomer seed formation, a condition that is mitigated by an indoor day tank rather than outdoor storage. The grade should not be mixed with amine-containing wetting agents during unreacted monomer hold, because alkaline conditions promote hydrolysis of VAM-derived acetate groups and can cause pH drift in the reactor delay.
Ethylene-vinyl alcohol resin is produced from an EVA precursor that is polymerised under high pressure with target vinyl acetate content between 25–75 wt% VAM, then saponified in methanol with sodium methoxide. Low-inhibitor VAM enters this chain at the EVA reactor, where it lowers the scavenger concentration that can otherwise create low-molecular-weight branches, unsaturation, and carbonyl impurities; after alcoholysis these impurities become chroma bodies and gel precursors in the EVOH melt. The saponification train is controlled by methoxide-to-acetate molar ratio and short residence time to maintain a hydrolysed degree above 99% for barrier grades, after which the resin is pelletised under nitrogen and dried to <0.1 wt% moisture before coextrusion. Melt extrusion of cast or blown barrier film uses a single-screw extruder with L/D 40–48, barrel temperatures from 180 °C to 235 °C, and die gap 0.4–0.9 mm; the EVOH layer is embedded between tie layers and polyolefin skins. Oxygen transmission rate is measured by ASTM D3985 at 23 °C/50% RH, with values for a 20 µm EVOH layer generally specified below 5 cm³/(m²·day·atm) depending on ethylene content and orientation. Compliance for food packaging is established under FDA 21 CFR 177.1360, EU Regulation 10/2011, and material characterisation per ISO 14663-2. Terminal product types include barrier films for processed meat and cheese, retort pouches, agricultural chemical bottles, cosmetic tubes, and automotive fuel tank barrier layers.
| Requirement | Standard / regulation | Critical parameter | Product impact |
|---|---|---|---|
| Material characterisation | ISO 14663-2 | melt mass-flow rate, density | extrusion viscosity specification |
| Oxygen barrier | ASTM D3985 | OTR at 23 °C/50% RH | packaging shelf life |
| US food contact | FDA 21 CFR 177.1360 | residual VAM, saponification by-products | direct food contact clearance |
| EU food contact | EU Regulation 10/2011 | overall migration, residual monomer | compliance declaration |
The processing boundary for EVOH based on low-inhibitor VAM is that gel formation accelerates when melt temperature exceeds 240 °C or when the saponified pellets are held at 70–80% RH prior to drying, which can create hydrolytic degradation and die-lip build-up. Coextrusion lines therefore use a dedicated desiccant hopper with dew point below -40 °C and limit residence time in the adapter below 10 min. Incompatibility arises if the EVOH layer is directly coextruded with an acidic sealant containing free maleic anhydride, which can cause acid-catalysed hydrolysis and edge gel at the die.
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Sinopec VAM LI Low Inhibitor Grade is a vinyl acetate monomer identified by CAS 108-05-4, molecular formula C4H6O2, and molar mass 86.09 g/mol. The grade is supplied as a low-inhibitor variant for downstream free-radical polymerizations requiring a shortened radical-scavenging delay and low residual phenolic loading. Producer sales specifications for vinyl acetate are typically aligned with ASTM D2190-07(2021) and, in the People’s Republic of China, GB/T 27573-2011; the low-inhibitor designation is expressed as a reduced hydroquinone monomethyl ether or hydroquinone control band relative to the conventional export grade. In a representative certificate of analysis, purity is not less than 99.8 wt%, water is not more than 0.04 wt%, acidity as acetic acid is not more than 0.005 wt%, and acetaldehyde is limited because it acts as a chain-transfer impurity that suppresses polyvinyl acetate molecular weight and contributes to chromophore formation during alkaline alcoholysis. The product is consumed in polyvinyl acetate homopolymers, vinyl acetate-ethylene emulsions, ethylene-vinyl acetate copolymers, polyvinyl alcohol, and formulated adhesives. The low-inhibitor designation does not mean unstabilized; it specifies a lower inhibitor set point that must be paired with nitrogen blanketing, controlled storage temperature, and batch consumption discipline.
| Parameter | Low-inhibitor grade | Conventional stabilized grade | Typical test method |
|---|---|---|---|
| Vinyl acetate purity | ≥99.8 wt% | ≥99.8 wt% | ASTM D2190-07(2021), GB/T 27573-2011 |
| Water | ≤0.04 wt% | ≤0.05 wt% | Karl Fischer titration, ISO 760 |
| Acidity as acetic acid | ≤0.005 wt% | ≤0.005 wt% | ASTM D2086 or producer titrimetry |
| Inhibitor as hydroquinone monomethyl ether | 1–3 mg/kg | 3–7 mg/kg | HPLC-UV or colorimetric redox |
| Acetaldehyde | ≤0.005 wt% | ≤0.005 wt% | GC-FID |
| Distillation range | 71.8–73.0 °C | 71.8–73.0 °C | ASTM D1078 |
Actual certificate of analysis values can be tighter depending on production unit and storage history; the producer batch certificate governs all individual shipments. Commercial low-inhibitor vinyl acetate monomer is also characterized by colour and distillation range. Colour is typically measured in platinum-cobalt units, with an acceptance limit of 5–10 Pt-Co; distillation range is specified so that low-boiling impurities such as methyl acetate and acetaldehyde or heavy ends such as acetic acid do not accumulate. The producer may report inhibitor as hydroquinone equivalents by HPLC with UV detection at 280 nm. A low-inhibitor grade retains a measurable stabilizer reserve; shipping under inert atmosphere without any radical scavenger is generally limited to integrated pipeline transfers within a single site.
Vinyl acetate free-radical polymerization is sensitive to inhibitor concentration because the monomer exhibits a high propagation rate coefficient and a strong chain-transfer-to-monomer constant. Hydroquinone and MEHQ act as stoichiometric radical traps: each molecule can consume two propagating radicals through hydrogen abstraction and semiquinone disproportionation. In an isothermal batch reactor, the induction period is approximately proportional to initial inhibitor concentration divided by effective initiation rate, 2 f kd [I]0, where f is initiator efficiency and kd is initiator decomposition rate coefficient. Reducing inhibitor from 5 mg/kg to 2 mg/kg therefore lowers the calculated induction time by roughly 60% at constant initiator loading. Published data for this specific configuration is limited, but the kinetic consequence is well established for vinyl acetate polymerization.
Vinyl acetate also has a high chain-transfer-to-polymer rate constant compared with styrene or methyl methacrylate, so low inhibitor levels accelerate onset more than they increase final molecular weight. Process development for low-inhibitor VAM must therefore be evaluated by induction time, conversion rate, and radical balance rather than molecular weight response alone. In acrylic systems, the same inhibitor shift might imply a larger molecular-weight adjustment; in vinyl acetate systems the dominant response is an earlier exotherm and a narrower start-up window.
The practical shift appears most clearly in solution and suspension polymerization, where monomer is not pre-emulsified. In a semibatch vinyl acetate emulsion reactor, the delay between persulfate injection and exotherm is a routinely used diagnostic for inhibitor content, air ingress, or initiator activity. With low-inhibitor VAM, this delay is compressed, so the control system must be qualified before the first production run. Typical hardware includes a 10,000 L glass-lined or 316L stainless steel reactor, a dual-flight helical ribbon agitator operating at 30–60 rpm, and a recirculating hot-water jacket capable of switching from heating to cooling within 2–3 °C of the reaction set point. The process conflict is that early initiation can increase the concentration of seed particles before the surfactant-stabilized particle-size distribution is fully established, raising viscosity and reducing heat transfer. In vinyl acetate-ethylene emulsions, the initial ammonium persulfate charge is often lowered from 0.05 wt% to 0.03 wt%, or the ethylene pressure ramp is delayed until 5–10% monomer conversion is confirmed by reaction calorimetry.
Solution polymerization in methanol for polyvinyl alcohol production also changes with low-inhibitor VAM. Water in vinyl acetate is hydrolyzed during reflux to acetic acid and acetaldehyde; acetaldehyde terminates growing polyvinyl acetate radicals and lowers the average degree of polymerization. The low-inhibitor grade is therefore supplied with tight moisture limits and is not normally substituted into continuous trains without re-tuning the methanol-to-monomer ratio. In alcoholysis, residual acetate groups in the final polyvinyl alcohol are determined by saponification degree testing in accordance with ISO 15023-2, and a lower inhibitor concentration reduces yellowing in the alkaline alcoholysis step. This effect is second-order compared with acetaldehyde and iron content, but it becomes significant when polyvinyl alcohol is targeted for low-colour optical films.
In high-pressure ethylene-vinyl acetate copolymerization at 100–300 MPa and 150–300 °C, vinyl acetate is one of the comonomers in the radical polymerization of ethylene. Inhibitor carryover from the VAM feed first contacts the peroxide initiator solution; MEHQ can consume peroxide-derived radicals before ethylene propagation begins. For a fixed autoclave residence time, a reduced inhibitor level increases apparent initiator efficiency and alters the molecular weight distribution and long-chain branching indices. The same reduction narrows the safe start-up window because oxygen contamination, copper-bearing alloy components, or localized peroxide concentrations can initiate runaway decomposition. Published data for this specific configuration is limited; process licensors usually require inhibitor content within a narrow band because high levels shift conversion and low levels reduce the margin to thermal runaway. The low-inhibitor grade is therefore appropriate when the EVA reactor has a dedicated VAM feed drum rather than a shared solvent/monomer header, preventing back-migration with stabilized material from another user.
Stirred high-pressure autoclaves for EVA are typically fabricated from thick-walled 316L stainless steel or alloy steel, with an L/D ratio in the range of 6:1 and a high-pressure diaphragm or plunger compressor on both ethylene and VAM feed. For low-inhibitor monomer, the VAM feed line should be checked for stagnant zones, dead legs, and threaded connections that can trap oxygen. A blocked VAM line downstream of the injection quill can polymerize faster than a stabilized grade, producing a plug that is difficult to remove at high pressure.
Storage and transfer of low-inhibitor vinyl acetate monomer require oxygen exclusion and temperature control. Vinyl acetate is flammable, with a closed-cup flash point near -8 °C, boiling point near 72.0 °C, and flammable limits of 2.6–13.4 vol% in air. For low-inhibitor product, inert blanketing is used to maintain residual oxygen below 5 vol%; transfer pumps should use double mechanical seals with pressure-rated barrier fluid to prevent air ingress. The product is not compatible with strongly alkaline aqueous solutions, amine-based inhibitors, or copper and copper alloys; copper ions accelerate inhibitor depletion and can form redox-active complexes. Tank and piping materials should be 304 or 316 stainless steel, or carbon steel with a suitable internal coating. Gaskets and pump diaphragms should be EPDM or PTFE because VAM swells nitrile and natural rubber. If as-received inhibitor content is below the specified lower limit or peroxide content exceeds the producer limit, the material should not be re-stabilized without a written procedure, because uneven distribution of fresh inhibitor can create localized uninhibited pockets.
In waterborne pressure-sensitive adhesives and UV-cure laminating adhesives, residual phenolic inhibitor can compete with photoinitiator absorption and contribute to colour formation during accelerated ageing. The low-inhibitor grade is selected to reduce UV absorption in the 250–350 nm region, where benzophenone and acylphosphine oxide photoinitiators require photon flux. The difference from a conventional grade is not linear; a reduction from 5 mg/kg to 2 mg/kg may improve cure speed more than the proportional inhibitor concentration change would suggest because the inhibitor also competes for dissolved oxygen and reacts with amine synergists. Adhesive film clarity is evaluated by ASTM D1003 haze and ISO 14782; colour change is measured by ISO 105-B02 or ASTM D3424. The product is used in film adhesives where residual phenolic compounds can migrate to the adhesive-substrate interface and react with alkaline fillers to form quinonoid chromophores. A boundary condition is pot-life in two-component formulations: the lower inhibitor level reduces the storage stability of unpolymerized monomer-containing formulations, so the formulated adhesive must be re-qualified with an added inhibitor package, such as 2–4 mg/kg of tert-butylcatechol or butylated hydroxytoluene.
| Downstream system | Difference from conventional grade | Boundary condition |
|---|---|---|
| PVAc emulsion for low-colour adhesives | Shorter persulfate induction; lower residual phenolic content | Earlier exotherm response required; lower initial initiator may be needed |
| Polyvinyl alcohol | Reduced quinonoid colour; tighter moisture and aldehyde management | Methanol-to-monomer ratio must be re-tuned |
| EVA high-pressure copolymer | Higher apparent initiator efficiency; narrower start-up margin | Dedicated VAM feed drum and oxygen-free transfer needed |
| UV-cure laminating adhesive | Improved photoinitiator photon competition; faster surface cure | Lower dark-storage stability; re-qualify inhibitor package |
Inbound inspection of the low-inhibitor grade should include density, water, acidity, and inhibitor concentration because the material has a narrower safe handling window than conventional stabilized grades. The density at 20 °C is approximately 0.934 g/cm³, the refractive index nD20 is near 1.395, and the normal boiling point is 72.3 °C. These values are confirmatory checks for contamination and grade mix-ups, not substitutes for specification compliance. Higher-than-ordered inhibitor concentration should not be blended into low-inhibitor service unless the destination process can tolerate the increased induction time and shifting initiator demand. Cross-contamination with styrene, acrylates, or methacrylates must be avoided because trace levels alter copolymerization reactivity ratios and can destabilize emulsion polymerization. Transfer lines should be bonded and grounded to prevent static discharge, and the product should be stored away from heat, direct sunlight, and ignition sources.
