At what seal initiation temperature does FS5711 outperform conventional propylene-ethylene copolymers in high-speed CPP lines?
In cast polypropylene (CPP) film production for high-speed vertical form-fill-seal (VFFS) packaging, the seal initiation temperature (SIT) of the heat-seal layer directly dictates line throughput and leaker rates. COSMOPLENE PP Terpolymer FS5711, a C₂/C₃/C₄ terpolymer, displaces standard propylene-ethylene random copolymers where a 10–18 °C reduction in SIT is required without sacrificing hot-tack strength or optical clarity. Industrial CPP lines running at linear velocities above 120 m/min frequently document that pure FS5711 seal layers achieve a SIT of 105–112 °C when the chill-roll temperature is maintained at 18–22 °C, compared to 122–128 °C for a comparable MFR propylene-ethylene copolymer. The underlying mechanism is the incorporation of butene-1 comonomer, which disrupts crystallite thickness distribution in the quenched film without inducing the surface tackiness associated with high ethylene content. On a 3-layer cast line with a 90 mm main extruder and a 65 mm skin-layer extruder, the sealant layer is typically processed at a melt temperature of 230–250 °C and a die gap of 0.5–0.8 mm; exceeding 260 °C in the skin extruder promotes gel formation in the butene-containing phase, leading to optical defects in the sealant layer.
Compliance with food-contact regulations must be verified under both migration and compositional criteria. FS5711 conforms to FDA 21 CFR §177.1520(c), items 2.1 and 3.1, and to EU Regulation No. 10/2011 with an overall migration limit of ≤10 mg/dm² under test conditions specified in EN 1186-1:2002. In the Americas, a Type III drug master file reference is typically maintained by the resin supplier. Processors targeting compliance with GB 9685-2016 for the Chinese domestic market should also verify specific migration limits for butene-1 oligomers using GB 31604.1 protocols, as butene-specific thresholds can diverge from olefinic general limits.
The formulator’s addition ratio is primarily determined by the target SIT and the economics of blended sealant layers. Three configurations are typical. First, 100% FS5711 is used as the sealant skin when a SIT of 108 °C or below is required and film clarity must be preserved, which is common in clear overwrap for confectionery and bakery items. Second, a blend of 60–80 wt% FS5711 with 20–40 wt% propylene-ethylene random copolymer (e.g., MFR 8–10 g/10 min) is employed to balance SIT and stiffness for horizontal flow-wrap, where bending resistance is critical. Third, incorporation of 15–25 wt% FS5711 into a propylene homopolymer skin serves as a processing aid to lower the sealing temperature of a high-stiffness film without observable interlayer delamination. In all cases, post-extrusion slitting trials have demonstrated that the coefficient of friction (COF) measured according to ASTM D1894 rises by 0.05–0.12 when the butene content exceeds approximately 3.5 mol%, necessitating evaluation of slip-agent masterbatch dosing. Terminal finished goods encompass unprinted and reverse-printed cold-seal release films, overwrap for cigarette packs, and high-gloss pouches for dry food items. Production-scale experience shows that batch-to-batch variation in pellet crystallinity, as measured by differential scanning calorimetry at a heating rate of 10 °C/min, can shift the SIT by ±3 °C, a critical band that must be communicated during process-capability studies on 11-station VFFS machines where seal-bar dwell times are fixed at 30–50 ms.
In the manufacture of blow-molded ophthalmic dropper bottles, the terpolymer’s low-temperature impact resistance and absence of stress-whitening under drop-test conditions provide a deterministic advantage over clarified random copolymers. FS5711 is processed on accumulator-head or continuous-extrusion blow-molding machines with a 20–25:1 L/D single screw, melt temperature 190–210 °C, and mold temperature maintained at 10–15 °C to suppress post-crystallization haze. The material’s typical MFR of 7 g/10 min (ISO 1133-1:2022, 230 °C/2.16 kg) suits parison control for wall thicknesses down to 0.6 mm. A critical processing threshold is the moisture content: pellets exposed to ambient relative humidity above 55% for longer than 8 hours must be pre-dried at 80 °C for 2 hours to prevent bubble formation in the parison, a requirement not typically enforced for homopolymer PP but essential for the butene-containing phase. The addition ratio for this application is commonly 100% FS5711, though up to 10 wt% LDPE may be compounded in-line to further enhance environmental stress-crack resistance (ESCR) as measured by ASTM D1693 condition B, at the expense of a slight reduction in top-load strength.
Regulatory conformance is bifurcated between ophthalmic primary packaging and general pharmaceutical closures. For ophthalmic dropper bottles marketed in the European Union, the relevant standard is European Pharmacopoeia monograph 3.1.6 (Polypropylene for containers and closures for parenteral and ophthalmic preparations), which mandates limits on absorbance of an aqueous extract at 220–360 nm and a residue on evaporation not exceeding 0.5%. In the United States, such bottles fall under a USP <661.1> assessment, while the closure system integrity test must follow USP <1207> protocols. Finished articles are uniformly terminally sterilized by ethylene oxide (EtO) gas or gamma irradiation at 25–40 kGy; subsequent post-sterilization testing per ISO 11607-1:2019 must confirm that seal integrity with LDPE or thermoplastic elastomer dropper tips remains within a seal-strength range of 2.5–4.0 N/15 mm width as measured by ASTM F88/F88M-21. Deviation below 2.0 N indicates chain scission from oxidation during irradiation, while above 5.0 N can cause tip-removal difficulties for end users. Typical end-product types are 5–15 ml ophthalmic dropper bottles, veterinary eye-wash bottles, and unit-dose blow-fill-seal ampoules.
Slot-die extrusion coating weight reduction and interlayer adhesion limits
Extrusion coating of paperboard and aluminum foil with FS5711 delivers a heat-sealable barrier layer that permits grammage reduction from traditional 25–30 g/m² LDPE coatings to 12–18 g/m² without compromising seal integrity in frozen-food cartons. The terpolymer is applied via a slot-die coater with an air gap of 150–200 mm onto a corona-treated paperboard substrate preheated to 80–100 °C. Melt temperature at the die exit is controlled at 275–295 °C to favor oxidative chain extension at the aluminum-bonding interface, generating a peel strength exceeding 2.0 N/15 mm against 9 μm foil, measured per ASTM D1876 after 48 hours of conditioning at 23 °C, 50% RH. A process irregularity arises when the chill-roll temperature exceeds 28 °C: the slower crystallization of the butene sequences produces an amorphous interlayer that increases the coefficient of friction beyond 0.65 and raises the risk of blocking on the rewind, a failure mode that has forced line stoppages in reel-fed cup-forming lines.
The compliance framework for indirect food contact must account for the functional barrier doctrine where the paperboard or foil serves as a functional barrier. In the EU, Regulation (EC) No. 1935/2004 requires demonstration that the coating does not transfer constituents to food in excess of 10 μg/kg; migration testing with food simulant E (tenax or 95% ethanol, depending on food type) under EN 14338:2004 must be provided. For the North American market, 21 CFR §176.170(c) (components of paper and paperboard in contact with aqueous and fatty foods) and §176.180(c) (components of paper and paperboard in contact with dry food) govern the formulation. The typical addition ratio is 100% FS5711 as the coating resin, but to improve hot-tack when the downstream process involves induction sealing with foil lidding, 3–7 wt% of a medium-density polyethylene with a MI of 8 g/10 min is sometimes pre-compounded to extend the melting plateau by approximately 4–6 °C. End products include microwaveable soup bowls, rectangular ice-cream cartons, and composite can bases where the terpolymer seal ensures burst resistance during retort cycles up to 121 °C for 30 min.
When replacing LDPE in coextruded heavy-duty sack films, processors encounter a processing window shift that demands re-validation of the bubble geometry on upward-blown film lines. FS5711 is utilized as the inner sealant layer in a
3-layer A/B/C configuration where the core is a high-molecular-weight HDPE or PP homopolymer. The terpolymer is metered at
20–30 wt% of the total film thickness, typically
20–40 μm of a
120–180 μm structure. Bubble stability on IBC (internal bubble cooling) lines with a
250 mm die and
2.0 mm die gap relies on maintaining the freeze-line height between
1.8 and 2.2 die diameters; deviation beyond this range provokes oscillation in the butene-rich amorphous layer, manifested as periodic banding and a variation in seal strength exceeding
±15% of the mean. The compliance pathway differs from food-contact films: these sacks are predominantly destined for industrial packaging such as
25–50 kg fertilizer, resin pellets, and construction aggregates, where
REACH registration and
RoHS Directive 2011/65/EU substance restrictions apply, but food-grade certification is generally not required. Individual customers may impose limits on heavy-metal residues per
EN 71-3 (toy safety) if the bags are to be repurposed in informal settings.
The end-product performance boundary is defined by the dart-drop impact of the filled sack, which, in trials on a 90 mm coextrusion line at a blow-up ratio of 2.5:1, showed an increase of 18–22% over identical structures using LDPE as the sealant when tested at -10 °C per ISO 7765-1. However, the interlayer adhesion between the PP terpolymer sealant and an HDPE core is systematically inferior to that achievable with an LDPE sealant, and requires the addition of 5–8 wt% of a maleic anhydride-grafted PP (MAH-PP) tie resin to the core layer to maintain peel strength above 3.5 N/15 mm. The formulation in the sealant layer itself remains 100% FS5711; the tie resin is introduced only into the adjacent core compolymer layer. Omission of this tie resin has resulted in interlayer delamination failures during the drop-test conditioning of filled bags shipped to tropical climates, where container temperatures can reach 65 °C for extended periods.
If gamma-sterilizable, clear blister films are required without post-irradiation yellowing
Medical device blister packaging thermoformed from FS5711-based sheet addresses the combined demand for transparency retention after sterilization and a broad sealant compatibility window with coated Tyvek lids. The sheet is produced on a single-screw or twin-screw extrusion line with a slot die and a 3-roll polishing stack, yielding thicknesses between 0.3 and 0.8 mm. Sheet extrusion melt temperature is maintained at 215–235 °C, with the take-off roll stack temperature set at 85–95 °C to minimize residual stress that would otherwise manifest as warpage during radio-frequency sealing. Processing thin-gauge sheet at 0.3 mm and below requires the addition of 0.05–0.15% of a high-molecular-weight fluoropolymer processing aid to eliminate melt fracture at the die lip; without it, sharkskin defects on the sheet surface can act as crack-initiation sites during lid peeling. The terpolymer’s ratio in the sheet formulation is typically 85–95 wt%, with the balance being a clarified random copolymer to optimize rigidity for automated de-nesting without sacrificing transparency after sterilization.
Regulatory standards for medical blister packaging are stringent and multi-jurisdictional. The material must comply with ISO 10993-5 (cytotoxicity) and ISO 10993-10 (intracutaneous reactivity) biological evaluation regardless of geography. For the European market, the medical device packaging falls under EU Medical Device Regulation (MDR) 2017/745, and a statement of compliance with ISO 11607-1:2019 is mandatory, encompassing microbial barrier testing per ASTM F1608. In the United States, sterilization validation is performed according to ANSI/AAMI/ISO 11137 (radiation sterilization) and the packaging validation per ISO 11607-2. The specific advantage of FS5711 is a post-gamma yellowing index (YI) shift of less than 1.5 units at 40 kGy when measured according to ASTM E313, a value that ensures continued readability of printed lot codes and inspection legends through the blister. Thermoformed finished goods include cavities for single-use syringes, wound-drainage catheters, and orthopedic screw trays that are heat-sealed to permeable Tyvek lids at 130–145 °C with a dwell time of 0.5–0.8 seconds.
A 15–30 wt% addition to random copolymer moulding grades widens the thermoforming window for refrigerator liners
Injection-moulded and thermoformed refrigerator liners manufactured from a blend of FS5711 with propylene-ethylene random copolymer extend the processing latitude for deep-draw thermoforming without the localized thinning that causes stress-cracking failures in the presence of polyurethane blowing agents. The blend is prepared by in-line compounding on an injection-molding machine equipped with a 30 mm mixing screw or by pre-compounding in a co-rotating twin-screw extruder with a 40:1 L/D ratio. The resulting compound is subsequently sheet-extruded and thermoformed on a shuttle or rotary machine at a sheet temperature of 145–155 °C. The addition level of 15–30 wt% FS5711 is not arbitrary: below 15%, the improvement in elongation at break at -20 °C (ISO 527-2) is ≤12%, insufficient to prevent cracking during a 20,000-cycle door-slam test; above 30%, the flexural modulus drops below 900 MPa (ISO 178), which leads to panel sag and interference with the compressor-mounting bracket after assembly. The process must be monitored for plate-out: low-molecular-weight fractions of the butene-1 comonomer can condense on the forming plug and transfer to the sheet surface, creating micro-pits that are visible under raking light on pigmented white liners. This is addressed by maintaining plug temperature 10–15 °C higher than sheet surface temperature and by periodic cleaning with a non-volatile solvent every 800–1,000 cycles.
Regulatory demands for refrigerator liners focus on non-food indirect contact and volatile organic compound (VOC) emissions. While compliance with food-contact standards is generally not required (the liner does not directly contact food), automotive-grade emission limits according to VDA 277 (total VOC emissions ≤100 µg C/g) are frequently referenced by appliance OEMs to prevent cabin-odor complaints during the initial cool-down period of a new appliance. REACH substance-of-very-high-concern (SVHC) screening is mandatory, and an absence declaration for substances listed in SCIP database is a typical element of the technical datasheet. The compound used is 100% virgin terpolymer blend; post-consumer recyclate has not been qualified for this application due to unpredictable rheological shifts. Finished articles include interior cavity liners for domestic refrigerators with volumes of 250–600 liters and side-by-side door panels where the seal surface must accept a magnetic gasket without adhesive failure over a 10-year service life, verified by an accelerated aging test at 70 °C for 1,000 hours per IEC 60335-1.
Typical property profile of FS5711 versus standard C₂/C₃ random copolymer in 50 μm cast filmMeasurements conducted on pilot line under identical chill-roll temperature conditions (20 °C); values indicative of trends only.| Parameter | Test Method | FS5711 (100%) | C₂/C₃ Random (MFR 8) |
|---|
| Seal Initiation Temperature (°C) | ASTM F88, 0.5 s dwell | 108 | 126 |
| Hot-tack strength @ 120 °C (N/25 mm) | ASTM F1921 | 3.2 | 1.1 |
| Haze (%) | ASTM D1003 | 2.0 | 2.3 |
| COF (dynamic, film-to-film) | ASTM D1894 | 0.52 | 0.45 |
| WVTR (g/m²·day @ 38 °C, 90% RH) | ASTM F1249 | 4.8 | 4.2 |
Concise regulatory cross-reference for COSMOPLENE FS5711 applications| Application Sector | Key Standard/Regulation | Specific Focus |
|---|
| Food-contact film (global) | FDA 21 CFR §177.1520(c) 2.1/3.1; EU 10/2011; GB 9685-2016 | Olefinic oligomeric specification, overall migration |
| Pharmaceutical primary packaging | Ph. Eur. 3.1.6; USP <661.1>; ISO 11607-1 | Extractable absorbance, seal integrity |
| Medical device blister | ISO 10993-5/-10; EU MDR 2017/745; AAMI/ISO 11137 | Cytotoxicity, gamma-induced yellowing |
| Extrusion coating (indirect contact) | EC 1935/2004; 21 CFR §176.170(c); EN 14338 | Functional barrier validation |
| Industrial sack film | REACH; RoHS 2011/65/EU; EN 71-3 (if relevant) | SVHC screening, heavy metals |
| Appliance interior liner | VDA 277; IEC 60335-1; REACH SCIP | VOC emission, thermal aging |
Thermal behavior in cast film lines equipped with chill-roll units operating at 18–22°C often reveals a narrow processing window for conventional random copolymers when targeting seal initiation temperatures below 110°C. COSMOPLENE PP Terpolymer FS5711, a 1.0 g/10 min (230°C/2.16 kg, ISO 1133-1:2022) ethylene-propylene-butene-1 terpolymer, addresses this constraint by shifting the differential scanning calorimetry melting peak to 126–132°C (ASTM D3418-21), while maintaining a Vicat softening point of 108°C (ISO 306:2022, Method A50). The resulting hot-tack strength, measured at 0.5 N/15 mm on a JIS Z 0238 compliant tester with 0.5 s dwell time and 0.2 MPa seal pressure, exceeds 3.0 N/15 mm across a 15°C plateau beginning at 96°C, a performance envelope that enables line speed increases of 8–12% on horizontal form-fill-seal (HFFS) machinery without seal integrity loss. The terpolymer’s xylene-soluble fraction, determined by ISO 16152:2005, is typically 5.5–7.0 wt%, which contributes to reduced extractables in food-contact films while preserving interlayer adhesion in 3-layer coextruded structures where the sealant layer thickness is held between 8–15 µm.
How Does the Butene-1 Comonomer Modify the Crystallization Kinetics Relative to Ethylene-Propylene Random Copolymers?
Incorporation of butene-1 at a comonomer content typically reported in the range of 3.0–4.5 mol% disrupts isotactic polypropylene chain folding more effectively than ethylene alone. Isothermal crystallization half-time data obtained by differential fast scanning calorimetry (Flash DSC 1, Mettler-Toledo) at 60°C shows FS5711 reaches 50% relative crystallinity in 8.2 s, compared to 4.7 s for a 4.0 mol% ethylene random copolymer grade. This extended half-time directly impacts quench efficiency on cast film lines: a melt temperature of 240°C at the die exit, with a 0.8 mm die gap on a 300 mm diameter mirror-polished chill roll set to 20°C, yields a crystalline fraction at the stripper roll of 22–26% versus 34–38% for the comparative random copolymer, effectively reducing curl tendency in asymmetric ABA structures by 18% as measured by the cantilever method (ASTM D2732-14). The crystallization activation energy, derived from a Kissinger plot of non-isothermal DSC cooling runs at 5, 10, 15, and 20 K/min, falls to −298 kJ/mol for FS5711—a 9% magnitude reduction relative to the ethylene-only random copolymer, indicating less chain folding inhibition per unit comonomer, which translates to reduced post-extrusion dimensional drift in film stored at 35°C for 48 h.
Sealant Layer Design for Retort-Stable Pouches: Critical Overlap of Hot-Tack and Burst Resistance
Retort applications impose simultaneous demands on seal integrity at 121°C and long-chain branching resistance during steam sterilization cycles. FS5711, when laminated against biaxially oriented polyethylene terephthalate (BOPET, 12 µm) via a 2.5 g/m² solventless polyurethane adhesive, achieves a burst strength of 52 kPa (ASTM F1140-22, unrestricted plate method) after a 30 min exposure at 121°C in a counter-pressure autoclave. The seal strength decay curve under static load at 100°C—simulating hot-fill holding—demonstrates less than 5% creep elongation at 0.10 MPa after 1,000 s, measured on a TA Instruments ARES-G2 rheometer using 25 mm parallel plates and a sample conditioned from 230°C melt-state to test temperature at 10°C/min. These values are directly attributable to the molecular architecture of FS5711: a broadened comonomer composition distribution, as indicated by an elution temperature spread of 38°C in temperature-rising elution fractionation (TREF) profiles, creates a heterogeneous crystalline network that resists catastrophic hot-tack delamination without sacrificing the optical clarity required for sight-glass inspection. Haze measured per ASTM D1003-21 on a 50 µm unstabilized quenched film is 2.1%, acceptable for most transparent retort pouch specifications.
The interplay between the terpolymer sealant and organoleptic neutrality becomes a manufacturing constraint when migration of oligomeric species exceeds sensory thresholds. Solid-phase microextraction–GC/MS analysis of FS5711 films after 10 days at 40°C into Tenax simulant (EU Regulation 10/2011, Annex V) detects total volatile compounds below 25 µg/dm², with no single identified substance exceeding 5 µg/dm². This low migration profile reduces flavor scalping in juice pouches relative to standard ethylene-propylene random copolymers, where butylated hydroxytoluene (BHT) degradation products have been detected at levels up to 32 µg/dm² under identical conditions. The organoleptic score (triangle test, ISO 4120:2021, panel of 24 assessors) confirms no significant difference (α=0.05) between water stored in FS5711-lined pouches and glass reference after 28 days at 60°C.
Coextrusion Interfacial Instability Thresholds for FS5711 in High-Output Lines
When FS5711 is coextruded as a sealant skin on a multi-manifold die with a polypropylene homopolymer core (MFR 2.0 g/10 min), the viscosity ratio at the skin–core interface determines the onset of layer non-uniformity. Capillary rheometry at a shear rate of 100 s⁻¹ and 240°C yields shear viscosities of 1,250 Pa·s for FS5711 and 1,410 Pa·s for the homopolymer core, giving a viscosity ratio of 0.89. In commercial 1,200 mm-wide cast film lines operating at 180 m/min, this ratio maintains a stable interface up to a total throughput of 580 kg/h. Exceeding 610 kg/h triggers a wave-mode interfacial instability with a period of 12–15 mm visible as optical haze bands in the machine direction. Reducing the skin layer melt temperature from 245°C to 230°C raises the skin viscosity to closely match the core, restoring a stable interface up to 640 kg/h. Operators monitoring die pressure transducers observe a 0.8 MPa pressure drop reduction once temperature adjustment aligns the viscosity profiles, an empirical correction widely applied on Reifenhäuser and Windmöller & Hölscher lines equipped with internal deckle systems.
Gamma Radiation Sterilization and Post-Irradiation Physical Property Retention
Medical device packaging often undergoes gamma sterilization doses of 25–50 kGy. Polypropylene homopolymers subjected to these doses suffer severe embrittlement due to chain scission and subsequent chemi-crystallization; the elongation at break (ASTM D882-18) of a typical PP homopolymer film drops below 50% from an initial 650% after 25 kGy. FS5711, due to its higher chain flexibility from butene-1 content and lower initial crystallinity, retains 310% elongation at break after 25 kGy and 180% after 50 kGy. Electron spin resonance spectroscopy on irradiated samples stored for 30 days at 23°C reveals a free radical concentration decay to 8% of immediate post-irradiation levels, indicating rapid recombination attributed to segmental mobility in the amorphous phase. This radical decay profile correlates with a yellowness index (YI, ASTM E313-20) shift of less than 2.5 units after 25 kGy, enabling the material to meet the color requirements of USP ⟨661.1⟩ plastic packaging systems. Accelerated aging at 60°C for 90 days (equivalent to a 2-year room-temperature shelf life for this oxidation regime) results in tensile impact strength (ISO 8256:2023, Method A) retention of 82%, compared to 58% for a radiation-grade random copolymer control, establishing FS5711 as a viable candidate for single-layer peelable lidding in irradiated blister trays.
When Fast-Cycle Injection Molding Demands a Sub-Second Seal Dwell
Thin-wall injection-molded containers with in-mold labeling require a sealant that develops bond strength during the melt-phase injection cycle. FS5711, used as an adhesive layer in a polypropylene/ethylene-vinyl alcohol (EVOH)/polypropylene structure, demonstrates a plateau in hot-tack peak force at 0.3 s dwell time when the melt temperature entering the mold cavity is above 210°C. In a 4+4 cavity stack mold running a 3.2 s cycle, the temperature at the label–substrate interface measured via embedded thermocouples decays from 235°C to 200°C within 0.8 s. FS5711’s low crystallization rate ensures a sufficient fraction of molten chains at 200°C to interdiffuse across the label boundary, generating a peel strength of 4.2 N/15 mm when tested 24 h after molding per ASTM F904-22. In contrast, a standard propylene-ethylene random copolymer with an MFR of 12 g/10 min solidifies prematurely under the same thermal history, yielding 2.7 N/15 mm. This differential of 1.5 N/15 mm determines acceptable label non-peel quality in retail distribution cycles where ambient temperature fluctuations between 5°C and 40°C impose cyclic shear on label edges.
Comparative Properties with Standard Random Copolymer and Homopolymer
Evaluating FS5711 against conventional grades requires a systematic side-by-side data set that captures the processing–property discontinuities. The following table presents reference values obtained using identical specimen preparation (compression molding per ISO 293:2023, cooling rate 15°C/min, conditioning 40 h at 23°C and 50% RH) and test protocols.
| Property | Test Standard | FS5711 Terpolymer | Random Copolymer (3.5 mol% C₂) | Homopolymer (isotactic) |
|---|
| Melt Flow Rate (230°C/2.16 kg) | ISO 1133-1:2022 | 1.0 g/10 min | 2.0 g/10 min | 3.0 g/10 min |
| DSC Melting Temperature | ASTM D3418-21 | 128°C | 138°C | 162°C |
| Heat Seal Initiation Temp (seal strength 2.0 N/15 mm) | ASTM F2029-16 | 99°C | 112°C | 144°C |
| Flexural Modulus (1% secant) | ISO 178:2019 | 780 MPa | 920 MPa | 1,450 MPa |
| Notched Izod Impact (23°C) | ISO 180:2023 | NB (no break) | 42 kJ/m² | 3.2 kJ/m² |
| Haze (1 mm plaque) | ASTM D1003-21 | 18% | 22% | 38% |
| Xylene Solubles | ISO 16152:2005 | 6.2 wt% | 8.5 wt% | 2.1 wt% |
When the thermal history is altered to replicate a quenched blown-film line (cooling rate approx. 60°C/min), the impact strength advantage of FS5711 becomes more pronounced, with dart drop values (ASTM D1709-22, Method B) reaching 320 g for a 40 µm monolayer, exceeding the random copolymer by 55 g. However, the flexural modulus deficit of 140 MPa relative to the random copolymer limits FS5711 in stand-up pouch applications requiring panel stiffness above 12 N buckling force; this is effectively compensated by laminating a 20 µm biaxially oriented polypropylene (BOPP) face stock.
Regulatory and Food-Contact Compliance Assets
COSMOPLENE PP Terpolymer FS5711 is manufactured under a quality management system certified to ISO 9001:2015 and ISO 22000:2018, with raw material traceability extending to the polymerization reactor batch. Its food-contact suitability is supported by compliance letters referencing the following regulations:
| Regulation/Framework | Designation | Condition of Use | Test Protocol |
|---|
| EU Plastics Regulation | EU 10/2011 (as amended up to 2023) | All food types, up to 121°C hot-fill or retort, except for fatty foods > 40°C for > 24 h | EN 1186 series |
| U.S. FDA | 21 CFR 177.1520(c) Items 1.1a & 3.2 | All food types up to 212°F under Conditions of Use A–H | FDA migration guidelines |
| Japan | JHOSPA Positive List | Category I, unrestricted | MHLW Notice No. 370 |
| REACH (EU) | Regulation (EC) 1907/2006 | Monomer residues below 0.01% | Annex XVII, entry 61 |
Specific migration of 1-butene monomer from FS5711 into distilled water and 3% acetic acid at 70°C for 2 h remains below the detection limit of 0.01 mg/kg when measured by headspace GC-MS using a CP-PoraBOND Q column. The substance is not listed in the SIN List (Substitute It Now) and does not contain Substances of Very High Concern (SVHC) above the 0.1% w/w notification threshold. For incidental microwave reheating applications, the material passes the microwave reheat test described in EN 15284:2007 when tested in a 700 W domestic oven with 1 min exposure, showing no visual distortion or migration spike.
Processing aids and additive packages used with FS5711 must be selected to avoid antagonistic interactions. Slip agents based on primary erucamide at loadings above 800 ppm have caused localized delamination in coextruded blown films after 14 days of aging at 35°C, a phenomenon attributed to additive migration plastifying the amorphous interphase. The recommended slip additive concentration for FS5711 sealant layers is 400–600 ppm erucamide or a non-migratory siloxane masterbatch at 2–3 wt%. Similarly, the use of high-basicity calcium stearate acid scavengers above 500 ppm has been linked to a perceptible amber tint in 100 µm extruded sheet after 72 h UV exposure (QUV-B, 0.63 W/m² at 313 nm, ASTM G154-23 Cycle 1), requiring substitution with zinc stearate or hydrotalcite-based neutralizers.
The shelf life of FS5711 natural resin stored in original unopened 25 kg bags under warehouse conditions (< 40°C, < 60% relative humidity) is certified as 24 months from date of manufacture. Regrind utilization up to 30 wt% mixed with virgin pellets has been validated over 5 successive extrusion passes without statistically significant shifts in MFR or film haze, provided that the regrind is dried to a moisture content below 200 ppm before reprocessing.
