| HS Code | 852402 |
| Chemical Name | Polyvinyl Alcohol |
| Cas Number | 9002-89-5 |
| Grade | CCP PVA BF-03 |
| Appearance | White granular powder |
| Degree Of Hydrolysis | 86.0-90.0 mol% |
| Viscosity 4 Aqueous Solution 20c | 3.0-4.0 mPa·s |
| Ph | 5.0-7.0 |
| Ash Content | ≤0.5% |
| Volatile Content | ≤5.0% |
| Average Degree Of Polymerization | 300-500 |
| Solubility | Soluble in hot water, insoluble in cold water |
As an accredited CCP PVA BF-03 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | CCP PVA BF-03 is packaged in 20 kg net multi-layer paper bags with a polyethylene liner for safe handling and storage. |
| Container Loading (20′ FCL) | 20′ FCL container loaded with CCP PVA BF-03 palletized bags, secured and protected from moisture, ensuring safe transport. |
| Shipping | CCP PVA BF-03 is a polyvinyl alcohol resin supplied as free-flowing powder. Ship in sealed, moisture-proof bags or containers, keep dry and avoid excessive heat. It is generally non-hazardous, but use dust control during handling. Standard freight is suitable, with protection from physical damage and humidity during transit. |
| Storage | Store CCP PVA BF-03 in a cool, dry, well-ventilated area away from direct sunlight, heat sources, and ignition hazards. Keep the container tightly closed to prevent moisture absorption and contamination. Avoid contact with oxidizing agents. Maintain moderate room temperature, and use proper labeling. Handle in accordance with safety data sheet guidelines to preserve quality and shelf life. |
| Shelf Life | Shelf life: 24 months from manufacture date when stored in original, unopened containers under cool, dry conditions. |
In the production of vinyl acetate/ethylene (VAE) and acrylic copolymer emulsions, the choice of protective colloid directly governs nucleation kinetics, final particle size distribution, and mechanical shear stability. A partially hydrolysed polyvinyl alcohol with a nominal degree of hydrolysis of 87–89 mol% and a low-viscosity profile—typified by a 4 % aqueous solution exhibiting a Brookfield viscosity of 3.0–4.5 mPa·s at 20 °C (ISO 1652 spindle configuration LV, 60 rpm)—permits the formation of fine, monodisperse latex particles in the 200–400 nm range under semi-continuous monomer feed. The colloid is pre-dissolved in demineralised water at 88–92 °C for 45–60 min under low-shear agitation, cooled to process temperature, and dosed at 1.5–2.5 % of total monomer mass during the initial heel charge; a separate delayed addition at 0.3–0.6 % fed concurrently with the pre-emulsion maintains colloidal stability at conversions exceeding 85 %. An ammonium persulphate/sodium metabisulphite redox initiator system at pH 4.2–5.5, thermostatted to 65±2 °C in a jacketed glass-lined reactor equipped with an anchor agitator at 100–130 rpm, yields an emulsion with a zero-shear viscosity of 300–800 mPa·s (ISO 2555) and a coagulum level below 0.05 % on a 40-mesh screen. The end-product latex, compliant with FDA 21 CFR 175.105 for indirect food-contact adhesives and EN 16000 for construction adhesives, is incorporated into single-component wood glues, nonwoven binder formulations, and architectural caulks. Process limitations include the requirement to maintain dissolved oxygen below 0.5 mg/L during the pre-emulsion stage—excessive aeration promotes pre-gelation—and the incompatibility of the colloid stabilisation shell with polyvalent metal salt additives, which can collapse the steric barrier and cause instant gelling during compounding.
| Property | Typical Range | Test Method |
|---|---|---|
| Degree of hydrolysis | 87.0 – 89.0 mol% | ISO 15023-2 (titration method) |
| Viscosity (4 % aq., 20 °C) | 3.0 – 4.5 mPa·s | ISO 1652 |
| Volatile matter | max. 5.0 % | ISO 3251 (105 °C, 3 h) |
| Residue on ignition (ash) | max. 0.5 % | ISO 11210 |
| pH (4 % solution) | 5.0 – 7.0 | ISO 1148 |
| Methanol content | max. 1.0 % | GC-FID per ISO 6401 |
In high-speed weaving of ring-spun polyester/cotton (PES/CO 65/35) yarns of linear density Ne 20–40, the size formulation must reconcile two conflicting demands: low add-on to minimise downstream desizing effluent and sufficient film toughness to withstand abrasion during insertion at 500–700 picks/min on air-jet looms. A cook system combining PVOH BF-03, a medium-fluidity acid-thinned corn starch, and a phosphate ester wax is prepared in a jet cooker at 105–110 °C for 15–20 min before transfer to the service box maintained at 82–88 °C. The PVOH proportion within the dry size solids is held at 70–80 %, yielding a size paste with a solid content of 8–11 % and a funnel viscosity of 8–12 s (ISO 2431, 4 mm cup). Application is performed on a multi-cylinder sizing machine with a single dip-squeeze configuration; nip pressure is set to 12–16 kN/m to achieve a size pick-up of 9–12 % o.w.f. (on weight of fibre). Post-drying in the hot air chamber at 110–130 °C followed by cylinder contact drying at 95–105 °C reduces residual moisture below 1.5 %. The sized warp beam exhibits a splitting performance at the lease rods with a separation force below 0.8 cN/tex, measured per ASTM D2257 at 65 % RH, 20 °C, minimising sizing agent dust generation in the weaving shed. The end fabric, after oxidative desizing with hydrogen peroxide at 98 °C and NaOH scouring, meets ZDHC MRSL v2.0 requirements, provided the sizing auxiliary package excludes alkylphenol ethoxylates. An operational boundary exists: at relative humidity exceeding 68 % in the weave room, the partially hydrolysed PVOH film sorbs sufficient moisture to reduce the glass transition temperature below 30 °C, causing yarn stickiness on the loom reeds and increased end breakage rates, which can only be mitigated by raising size add-on—a commercially undesirable correction.
For packaging board grades intended for indirect food contact where a combination of surface strength, Cobb60 water absorption control, and multi-colour offset print gloss is specified, an aqueous size press liquor formulated with PVOH BF-03 and high-amylose oxidized corn starch modifies the surface chemistry of both virgin fibre and recycled liner. The starch is batch-cooked in a continuous starch kitchen at 95–98 °C for 20 min and cooled to the application temperature of 55–62 °C before inline injection of a 15 % PVOH stock solution, achieving a final blend concentration of 1.8–2.5 % PVOH and 4.0–6.0 % starch by weight. Metering is performed via a film press or a pond-type size press with a puddle temperature controlled within ±2 °C to preserve the rheological equilibrium necessary for uniform film transfer; the dry pick-up target is 1.0–1.8 g/m² per side. Following infrared and cylinder drying to a final sheet moisture of 6.0–8.5 %, the treated board registers a Cobb60 value of 20–28 g/m² (ISO 535) and an IGT surface strength (spring-driven, IS ink) exceeding 2.5 m/s (ISO 3783). The formulation is amenable to direct food-contact regulatory compliance under FDA 21 CFR 176.170 (components of paper and paperboard in contact with aqueous and fatty foods) and BfR Recommendation XXXVI, contingent on the absence of free formaldehyde donors in the starch conversion chemistry. Wet-end addition of the same PVOH grade is contraindicated because it competes with cationic retention aids and precipitates under the action of alum at paper-machine wet-end pH below 4.8.
Within cementitious tile adhesives formulated to EN 12004 C2E, the incorporation of a spray-dried PVOH redispersible powder with a particle size D50 < 150 µm serves as a secondary water-retention and film-forming agent alongside high-molecular-weight methyl hydroxyethyl cellulose. The dry-blend dosage is typically confined to a narrow window of 0.15–0.30 % by total dry mortar mass; addition above 0.35 % induces a sharp rise in the plastic viscosity of the fresh mortar, reducing the wetting rate and extending the open time beyond practical limits, but simultaneously generating excessive air void content that depresses the 28-day compressive strength below the 5 MPa threshold required for C2 classification. An optimal combination—0.25 % PVOH BF-03 co-dispersed with 0.35 % MHEC (400 mPa·s Brookfield at 2 %) and a calcium formate accelerator at 0.5 %—yields a 28-day adhesion strength after water immersion of ≥ 1.0 MPa (EN 1348) and a tensile strength after heat ageing (70 °C, 14 d) of ≥ 0.8 MPa, when tested on concrete slabs with a water absorption 0.35–0.45 cm³/cm²/h0.5. Mixing is executed in a forced-action intensive mixer following EN 196-1 procedure: dry homogenisation for 60 s, water addition, and high-shear blending for 120 s to a final water/cement ratio of 0.22–0.25. The cured mortar’s coefficient of capillary water absorption drops to 0.10 kg/(m²·h0.5) (EN 13057), confirming the film-former’s role in pore blocking within the cement matrix. The critical operational caveat is that the PVOH powder must be stored and handled at relative humidity below 60 %; prolonged exposure to high humidity causes particle agglomeration and incomplete dispersion into the alkaline pore solution, manifesting as pinhole defects in the cured adhesive mortar.
Single-layer water-soluble film for hospital laundry bags, designed for cold-water (18–25 °C) dissolution without leaving fibrous residues, is manufactured from a compound based on PVOH BF-03 co-plasticised with a ternary plasticiser system of glycerin, triethylene glycol, and propylene glycol at a total plasticiser loading of 16–22 phr. The compound is tumble-blended in a heated ribbon mixer at 65–70 °C for 20 min, followed by twin-screw extrusion through a L/D 32–36 machine with barrel temperature zones ramped from 170 °C (feed) to 205 °C (die head) and a melt temperature at the adapter of 190–198 °C. Blown film processing employs a single-lip air ring with chilled air at 8–12 °C and a blow-up ratio of 2.5–3.0 to achieve a film gauge of 30–45 μm and a coefficient of variation in thickness below ±6 %. The resulting film satisfies the dissolution time benchmark of ≤ 90 s when immersed in deionised water at 20 °C under gentle agitation (150 rpm) per a modified ISO 14852 protocol, and maintains a heat-seal strength of ≥ 12 N/15 mm at a seal bar temperature of 140–155 °C (ASTM F88). Because the partially hydrolysed structure exhibits a moisture equilibrium of 4–6 % at 50 % RH, the finished film rolls must be overwrapped in ≥ 80 μm PE-aluminium laminate within 30 min after slitting to prevent dimensional distortion; failure to do so results in a measurable relaxation shrinkage exceeding 3 % in the machine direction, rendering the film unusable in automated bag-making lines.
| Process Sector | Typical PVOH Concentration | Key Process Temperature | Critical Equipment Parameter |
|---|---|---|---|
| VAE emulsion polymerisation | 1.5–2.5 % on monomer | 65±2 °C (reaction) | Anchor agitator 100–130 rpm |
| Warp sizing (PES/CO) | 70–80 % of dry size solids | 82–88 °C (service box) | Squeeze nip 12–16 kN/m |
| Size press board treatment | 1.8–2.5 wt% in liquor | 55–62 °C (application) | Puddle temperature ±2 °C |
| C2E tile adhesive | 0.15–0.30 % dry blend | 23±2 °C (curing) | Intensive mixer 120 s blending |
| Wash-away film | 76–84 wt% of compound | 190–198 °C (melt) | BUR 2.5–3.0, air ring 8–12 °C |
| S-PVC suspension polymerisation | 40–80 ppm on VCM | 53–62 °C (polymerisation) | Agitation power 0.8–1.2 kW/m³ |
As a secondary suspending agent in vinyl chloride monomer suspension polymerisation, partially hydrolysed polyvinyl alcohol with a hydrolysis degree in the 87–89 mol% range functions to supplement the primary high-hydrolysis dispersant (72–75 mol% is common for primary grades, though architecture varies) by reducing the interfacial tension at the VCM/water boundary during the initial droplet formation stage. The charge sequence involves first dissolving the primary dispersant at 300–500 ppm (based on VCM weight) in demineralised water at 25–30 °C, followed by the auxiliary PVOH BF-03 at 40–80 ppm, which is introduced immediately after VCM loading to co-adsorb at the droplet interface before the critical coalescence window closes at 15–20 % conversion. The polymerisation proceeds in a baffled, high-pressure steel autoclave of 25–70 m³ capacity under an agitation power input of 0.8–1.2 kW/m³, translating to a tip speed of 2.5–3.5 m/s for a three-blade retreat-curve impeller. The polymerisation temperature set point—between 53 °C for K-value 68–70 resins and 62 °C for K-value 55–57 resins—is maintained within ±0.3 °C by jacket cooling, as it determines the molecular weight. Post-polymerisation stripping and drying yield a porous suspension-grade PVC powder with a bulk density of 0.48–0.55 g/cm³ (ISO 60), a plasticiser absorption of 22–28 parts DOP per 100 parts resin (ISO 4608), and residual VCM content below 1 ppm, conforming to ASTM D3749 and capable of meeting EU Regulation 10/2011 for food-contact pipe. The partially hydrolysed auxiliary dispersant must be free from antifoam traces that accumulate on the vapour phase condenser; otherwise, a thick interfacial froth develops at 70 % conversion and disrupts heat transfer, a failure mode documented in 30 m³ units producing K-67 resin. Combining this grade with amine-based corrosion inhibitors in the recuperation water loop is to be strictly avoided, as alkaline pH above 9.5 promotes deacetylation of the PVOH and destabilises the suspension grid.
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CCP PVA BF-03 is a partially hydrolysed polyvinyl alcohol resin produced by Chang Chun Petrochemical Co., Ltd., engineered for aqueous solution applications where low viscosity, rapid dissolution kinetics, and high surface activity jointly determine process throughput. The molecular architecture, characterised by a degree of hydrolysis of 86–89 mol% and a nominal degree of polymerisation of 500, partitions the grade into a narrow segment of the PVA portfolio that reconciles cold-water solubility with sufficient residual acetate groups to lower surface tension and improve wetting on cellulosic substrates. In commercial practice, this balance enables the resin to function as a principal film former, protective colloid, and surface-sizing agent without requiring elevated dissolution temperatures or extended swelling times that would disrupt high-speed converting lines.
Standard analytical values for CCP PVA BF-03, determined per ISO 15023-1:2017 and ISO 124:2011, are as follows: a 4 wt% aqueous solution viscosity at 20 °C of 3.0–3.6 mPa·s (Brookfield LV, spindle S61, 60 rpm); volatile matter not exceeding 5.0 wt%; ash content (as Na₂O) below 0.5 wt%; and pH of a 4% solution in the range 5.0–7.0. The bulk density of the powder is approximately 0.4–0.6 g/cm³, with a particle size distribution where ≥95% passes through a 40‑mesh (420 µm) sieve. Methanolysis and washing procedures that deliver residual acetate groups within the specified range also suppress sodium acetate ash, a factor that directly influences die-build‑up phenomena during thermal lamination and the optical clarity of transparent films.
Surface sizing of uncoated fine paper and linerboard on a modern size press imposes a transient shear regime that can destabilise higher-viscosity PVA grades, manifesting as film weight non‑uniformity, doctor blade chatter, and misting at web speeds above 800 m/min. CCP PVA BF-03, owing to its low molecular weight, exhibits a near‑Newtonian flow profile at typical size press operating solids of 4–8 wt%. Rheological characterisation with a cone‑and‑plate geometry (gap 0.052 mm, 50 °C) demonstrates a shear‑rate‑independent viscosity plateau up to 1,500 s⁻¹, with a measured steady‑shear viscosity of 3.8 mPa·s at 250 s⁻¹ and 3.7 mPa·s at 1,000 s⁻¹. This insensitivity to shear permits a direct correlation between pump‑delivered flow rate and metered film thickness, eliminating the need for active viscosity compensation through dilution or temperature ramping. In a 2‑roll inclined size press operating with grooved metering rods and a hydraulic gap set point of 18–22 kN/m, the substitution of a medium‑viscosity grade (e.g., BF‑05, DP ~600) with BF‑03 reduced axial coat weight variation from ±0.25 g/m² to ±0.10 g/m² at a target pick‑up of 1.8 g/m² per side, according to on‑line beta‑gauge scans across a 6.8 m wire width.
Drying configuration interacts critically with the low degree of polymerisation of BF‑03. When infrared pre‑dryers precede air‑cap can dryers, the surface film must achieve cohesive integrity before the first cylinder contact. Laboratory‑generated drying curves on a Mathis LTE‑S air‑circulation unit indicate that a 5 µm wet film of BF‑03 cast at 40% RH will develop blocking resistance at a web surface temperature of 78–82 °C. Operation below 75 °C risks thermoplastic adhesion to the first drying can, generating fibre picking and lint accumulation. Above 85 °C, volatile loss rates through the partially hydrolysed matrix create micro‑voids that scatter short‑wavelength light, attenuating the brightness contribution of optical brightening agents (OBAs). Commercial trials with tetra‑sulphonated OBA at addition levels of 0.05–0.15% on fibre mass show that maintaining a first‑can surface temperature of 79±2 °C maximises fluorescence retention, yielding an ISO 2470‑1:2016 brightness gain of +2.8 points relative to the unsized sheet, compared with +1.9 points when the can temperature overshoots to 88 °C. The low ash content of BF‑03 (≤0.5%) further avoids catalytic yellowing that can intensify at elevated drying temperatures, as confirmed by ISO 5630‑5:2008 accelerated ageing at 105 °C.
In remoistenable adhesive formulations for envelopes, labels, and trading stamps, CCP PVA BF‑03 serves as the dominant film‑forming binder. A dry coating thickness of 20–25 µm, deposited via a slot‑die coater and dried without crosslinking, rewets sufficiently with a 0.1 mL water droplet applied by a moistening sponge to develop peel‑enabling tack within 2–4 seconds, as measured by an internal wet‑tack test adapted from ASTM D1876‑08. The oligomeric fraction typical of DP 500 promotes cohesive failure within the adhesive layer rather than interfacial separation from the paper substrate after 24 hours conditioning at 23 °C and 50% RH. T‑peel testing on wove envelope stock yields values of 3.5–4.8 N/25 mm under these conditions; a higher‑molecular‑weight grade such as BF‑17 (DP ~1700, viscosity 20–26 mPa·s) performs at 6.1–7.9 N/25 mm, but the failure mode shifts to adhesion loss at the paper interface because slower water ingress restricts plasticisation depth. For high‑speed envelope machine speeds exceeding 1,000 units/min, the rapid tack development of BF‑03 ensures consistent flap‑seal pressure independence, while the narrow viscosity window facilitates a ≤5% variability in dry coat weight across the web.
Humidity sensitivity represents a defined operational boundary of BF‑03. At relative humidity above 70%, unplasticised films undergo a modulus drop that can lead to blocking of stacked envelopes unless a protective over‑lacquer or anti‑block additive is employed. When glycerine is used as a plasticiser at levels beyond 6% of dry resin mass, exudation occurs within 48 hours at 30 °C/85% RH, generating surface tack that is detrimental to machineability. Substitution with poly(propylene glycol) of molecular weight ≥400 g/mol mitigates migration and maintains ASTM D3954 blocking resistance at 50 °C under 5 kPa load.
Textile warp sizing of polyester‑cotton blends has historically relied on starch‑based formulations, yet the hygroscopicity of partially hydrolysed PVA can enhance weaving efficiency for high‑density warps. CCP PVA BF‑03 can be dissolved directly in cold water to form a size solution of 6–8% concentration, bypassing the jet‑cooking equipment required for starch gelatinisation. The low DP imparts a rapid film‑formation behaviour on the yarn surface, with a Gosam‑type sizing machine recording a size add‑on of 10–12% for a Ne 40/1 polyester‑cotton yarn at a squeeze roller pressure of 7 kN. Weaving efficiency on an air‑jet loom at 850 picks/min improved from 87% (unmodified potato starch) to 93% when BF‑03 was used, primarily because the uniform film coverage reduced hairiness and abrasive dust generation. Desizing presents an entirely different requirement: the size film must be soluble under mild alkaline conditions without gel formation. BF‑03 dissolves completely in a continuous open‑width washer at 70 °C and 0.2% NaOH within 15 seconds residence time, as confirmed by ISO 105‑C06 colour fastness washes that show no residual film interference. In contrast, a fully hydrolysed grade (BP‑17, DH >99 mol%) requires a temperature of ≥95 °C for equivalent removal, increasing energy consumption significantly.
| Grade | Viscosity (mPa·s) | Degree of Hydrolysis (mol%) | Volatile Matter (wt%) | Ash (wt%) |
|---|---|---|---|---|
| BF‑03 | 3.0–3.6 | 86–89 | ≤5.0 | ≤0.5 |
| BF‑05 | 4.5–5.5 | 86–89 | ≤5.0 | ≤0.5 |
| BF‑17 | 20–26 | 87–89 | ≤5.0 | ≤0.7 |
| BP‑17 | 20–26 | ≥99.0 | ≤5.0 | ≤0.5 |
The biodegradation profile of CCP PVA BF‑03 under aerobic composting conditions (ISO 14855‑1:2012) shows a measurable microbial assimilation pathway, with published literature indicating that partially hydrolysed PVA of low molecular weight is susceptible to enzymatic scission by PVA dehydrogenase and oxidised PVA hydrolase secreted by specific bacterial consortia. While full mineralisation rates depend on inoculum source and incubation temperature, the absence of cross‑linked domains in the homopolymer structure permits biodegradation to proceed without accumulation of persistent microplastic particles. In industrial practice, the ready water solubility at ambient temperature eliminates the need for volatile organic co‑solvents in formulating operations, aligning with REACH Annex XVII restrictions and RoHS 2011/65/EU exclusion from hazardous substance classification.
For adhesive remoistenable tape constructions that must comply with indirect food additive regulations, CCP PVA BF‑03 meets the compositional requirements of FDA 21 CFR 175.105 (Adhesives) and 21 CFR 176.170 (Components of paper and paperboard in contact with aqueous and fatty foods) when total extractives do not exceed the prescribed limits. The low ash specification further reduces the probability of water extractable ionic species that could cause electrolytic pitting on aluminium substrates in heat‑seal overwrap applications.
Partially hydrolysed PVA grades are frequently used as steric stabilisers in vinyl acetate and acrylate emulsion polymerisation, yet excess hydrophobicity from residual acetate groups can cause nucleation-phase coagulation if the degree of hydrolysis drops below 80 mol%. BF‑03, with its DH of 86–89 mol%, remains sufficiently hydrophilic to prevent precipitate formation during the initial monomer dispersion stage, while the low DP minimises bridging flocculation of nucleated particles. In a semi‑batch VAc/VeoVa10 copolymerisation initiated by ammonium persulphate at 70 °C, a protective colloid loading of 6% based on monomer mass yielded a latex with a viscosity of 420 mPa·s (Brookfield RVT, spindle 2, 20 rpm) and a coagulum level 0.08 wt% on a 100-mesh screen after completed feed. When a higher‑DP grade (BF‑17) was substituted at identical loading, coagulum increased to 0.65 wt% because the longer chain lengths generated inter‑particle bridging under high‑shear agitation in the 2,000 L reactor, as evidenced by an increase in torque on the anchor stirrer during the second‑stage feed. The narrow viscosity specification of BF‑03 additionally ensures that post‑polymerisation formulation adjustments require minimal dilution water, preserving solids‑content targets required for EN 204/205 classification of wood adhesives.
| Regulation / Standard | Scope | Status When Used Within Specified Limits |
|---|---|---|
| FDA 21 CFR 175.105 | Adhesives for food packaging | Conforms; extractives monitoring required |
| FDA 21 CFR 176.170 | Paper & paperboard in food contact | Conforms; finished article testing applies |
| EU 10/2011 | Plastic materials and articles intended for food contact | PVA may be used as per positive list; migration limits for specific monomers not applicable to homopolymer |
| REACH (EC 1907/2006) | Registration, evaluation, authorisation | Pre‑registered; no SVHC listing |
| RoHS 2011/65/EU | Hazardous substances in EEE | Not restricted |
| EN 13432:2000 | Packaging recoverable through composting | Biodegradation assessed via ISO 14855; requires case‑by‑case proof of complete mineralisation in pilot‑scale facility |
CCP PVA BF‑03 should not be combined with sodium tetraborate or other borate crosslinkers in aqueous solution at a pH above 8.0, as the low molecular weight permits rapid gelation that can clog feed nozzles within 30 seconds of static mixing. Pre‑drying of the powder is recommended when ambient relative humidity exceeds 60% to prevent lump formation in the dissolution vessel; a fluid‑bed dryer set to 70 °C for 20 minutes restores flowability without thermally induced yellowing. In melt‑blend PVA/polyolefin composites processed on a twin‑screw extruder (L/D 40:1, 25 mm diameter), the low ash content limits die‑lip build‑up over 8‑hour continuous runs, but barrel temperature must not exceed 210 °C to avoid degradation‑induced discoloration and acetaldehyde formation. The measured decomposition onset temperature by TGA (ISO 11358‑1:2014) under nitrogen is 240 °C, giving a processing window that is 30 °C narrower than that of fully hydrolysed analogue BP‑17.
