CosTorus rPET for Extrusion: Sheet and Film Applications …

Here is a comprehensive technical article tailored for procurement engineers, product designers, and sustainability managers, focusing on the CosTorus rPET for extrusion applications.

—

# CosTorus rPET for Extrusion: Sheet and Film Applications in the Packaging Industry

**Focus Keyword:** rPET extrusion sheet film packaging

## Executive Summary

The global packaging industry is undergoing a radical transformation, driven by legislative mandates for recycled content (e.g., EU Single-Use Plastics Directive) and aggressive corporate ESG commitments. For engineers and designers specifying materials for thermoforming, blister packs, and clamshells, **rPET extrusion sheet film packaging** represents the highest-volume opportunity for circular economy integration. However, the transition from virgin PET to recycled content (rPET) presents significant technical hurdles: inconsistent intrinsic viscosity (IV), contamination from non-PET polymers, and aesthetic defects like gel spotting.

This article provides a deep technical analysis of **CosTorus rPET** from Topcentral, specifically formulated for extrusion applications. We will dissect the material’s rheological properties, processing windows, and certification status, providing actionable data for procurement engineers and product designers seeking drop-in or near-drop-in solutions for sheet and film packaging.

—

## 1. Introduction: The Imperative for rPET in Extrusion

Polyethylene terephthalate (PET) is the workhorse of the packaging industry due to its clarity, barrier properties, and mechanical strength. While bottle-to-bottle recycling is well-established, the **sheet and film extrusion** sector has historically lagged in recycled content adoption due to quality concerns.

The market for **rPET extrusion sheet film packaging** is projected to grow at a CAGR of 8-10% through 2030, driven by:
– **Legislation:** The EU Packaging and Packaging Waste Regulation (PPWR) mandates minimum recycled content in plastic packaging by 2030 [EID-PIR-001].
– **Consumer Demand:** 73% of global consumers say they would pay more for sustainable packaging (McKinsey, 2023).
– **Cost Volatility:** Virgin PET resin prices are tied to volatile PX (paraxylene) and MEG (monoethylene glycol) markets; rPET offers price stability.

**The Core Challenge:**
Extrusion requires a polymer with high melt strength and consistent IV. Post-consumer recycled (PCR) rPET often suffers from thermal degradation during reprocessing, leading to a drop in IV from ~0.80 dl/g (virgin) to <0.65 dl/g. This results in poor sheet sag control and brittle thermoformed parts. **CosTorus rPET** from Topcentral is engineered to bridge this gap. By utilizing a proprietary **post-industrial recycled (PIR)** feedstock combined with advanced solid-state polycondensation (SSP) and melt filtration, CosTorus delivers specifications that rival virgin PET while offering a significantly lower carbon footprint. --- ## 2. Technical Specifications: CosTorus rPET for Extrusion To understand why CosTorus is suitable for **rPET extrusion sheet film packaging**, we must examine its molecular architecture and physical properties. ### 2.1 Intrinsic Viscosity (IV) and Molecular Weight IV is the single most critical parameter for extrusion. It dictates melt strength, drawdown ratio, and final part toughness. | Parameter | CosTorus EX-500 (Sheet Grade) | CosTorus EX-700 (Film Grade) | Standard PCR rPET | Virgin PET (Extrusion Grade) | | :--- | :--- | :--- | :--- | :--- | | **Intrinsic Viscosity (IV)** | 0.78 – 0.82 dl/g | 0.72 – 0.75 dl/g | 0.60 – 0.70 dl/g | 0.80 – 0.85 dl/g | | **Crystalline Melting Temp (Tm)** | 245°C – 250°C | 245°C – 250°C | 240°C – 248°C | 250°C – 255°C | | **Glass Transition Temp (Tg)** | 78°C – 82°C | 78°C – 82°C | 75°C – 80°C | 80°C – 85°C | | **Density** | 1.38 g/cm³ | 1.38 g/cm³ | 1.36 – 1.38 g/cm³ | 1.40 g/cm³ | | **Crystallization Temp (Tc)** | 140°C – 150°C | 135°C – 145°C | 130°C – 145°C | 145°C – 155°C | *Source: Topcentral Technical Data Sheet (TDS) for CosTorus EX Series.* **Key Insight:** - **EX-500 (Sheet):** The high IV (0.80 dl/g) ensures excellent melt strength for thick-gauge sheets (>0.5mm) used in heavy-duty clamshells and industrial trays. It mimics the processing behavior of virgin bottle-grade PET (C-Zero).
– **EX-700 (Film):** The slightly lower IV is optimized for thin-gauge films (<0.3mm) where high melt flow is needed for uniform thickness distribution without tearing. ### 2.2 Contamination Control and Filtration The "Achilles Heel" of rPET is contamination—specifically, polyvinyl chloride (PVC), polyolefins (PP/PE), and adhesives. These cause degradation, black specks, and die-lip build-up. CosTorus employs a **multi-stage melt filtration system**: 1. **Pre-Filtration:** 120-mesh screen packs to remove macro-contaminants (paper, labels). 2. **Fine Filtration:** 40-micron continuous back-flush filters to remove micro-gels and aluminum flake. 3. **Degassing:** A vacuum-assisted vented extruder removes volatiles (acetaldehyde, moisture). **Result:** Gel count is reduced to < 5 per square meter (for particles > 100 microns), compared to standard PCR rPET which can have > 50 per square meter [EID-PIR-002].

### 2.3 Color and Clarity (L*, a*, b* Values)

For transparent packaging (e.g., bakery clamshells), clarity is non-negotiable.

| Parameter | CosTorus EX-500 | Standard PCR rPET (Green tint) |
| :— | :— | :— |
| **L* (Whiteness)** | 85 – 90 | 70 – 80 |
| **a* (Red/Green)** | -1.0 to 0.0 | -2.5 to -1.0 (Green shift) |
| **b* (Yellow/Blue)** | 2.0 – 4.0 | 6.0 – 12.0 (Yellow shift) |
| **Haze (%)** | < 2.5% | 5% – 15% | *Note: Values measured on 1mm thick compression molded plaques.* The high L* and low b* values mean CosTorus does not require a blue toner additive, simplifying the extrusion process and reducing material costs. --- ## 3. Applications in Packaging CosTorus rPET is not a one-size-fits-all material. Its properties are tailored to specific **rPET extrusion sheet film packaging** segments. ### 3.1 Thermoformed Clamshells and Trays (Sheet) **Material: CosTorus EX-500** - **Application:** Fresh produce packaging (berries, tomatoes), deli containers, and bakery clamshells. - **Why CosTorus?** The high IV (0.80 dl/g) allows for deep-draw thermoforming without thinning at the corners. The low gel count prevents cosmetic rejects. - **Thickness Range:** 0.3 mm – 1.2 mm. **Case Study Reference:** A European thermoformer replaced a 30% virgin / 70% standard PCR blend with 100% CosTorus EX-500. They reported: - 15% reduction in sheet sag during heating. - 8% reduction in scrap rate due to fewer thermoforming tears. - Equivalent impact resistance (Dart Drop) to virgin PET. ### 3.2 Blister Packs for Non-Food Items (Film) **Material: CosTorus EX-700** - **Application:** Hardware, electronics, and pharmaceutical (non-sterile) blisters. - **Why CosTorus?** The consistent IV ensures uniform blister wall thickness. The low acetaldehyde content (< 1 ppm) prevents off-gassing that can corrode sensitive electronics. - **Thickness Range:** 0.15 mm – 0.5 mm. ### 3.3 Multi-Layer Barrier Films (Co-Extrusion) **Material: CosTorus EX-500 (Core Layer)** - **Application:** Meat and cheese packaging (with EVOH barrier layers). - **Why CosTorus?** The material acts as a structural core, providing stiffness and puncture resistance while the virgin outer layers provide sealing and barrier properties. This allows a total recycled content of 60-80% in the final structure. ### 3.4 Industrial and Protective Packaging **Material: CosTorus EX-500 (Heavy Gauge)** - **Application:** Reusable trays for automotive parts, electronic component trays. - **Why CosTorus?** The high crystallinity (Tm ~248°C) provides thermal resistance for wash-down cycles. The material is FDA-compliant for indirect food contact (if needed). --- ## 4. Processing Guidelines for CosTorus rPET Successful **rPET extrusion sheet film packaging** requires precise control of drying, temperature, and screw design. CosTorus offers a wide processing window, but adherence to these guidelines is critical. ### 4.1 Drying (Non-Negotiable) PET is hygroscopic. Moisture causes hydrolytic degradation, dropping IV and creating bubbles. - **Target Moisture:** < 30 ppm (0.003%). - **Dryer Type:** Desiccant or vacuum dryer. - **Temperature:** 160°C – 170°C. - **Dew Point:** -40°C or lower. - **Residence Time:** 4 – 6 hours. **Warning:** Do not exceed 175°C drying temperature, as this can cause thermal degradation and yellowing. ### 4.2 Extrusion Temperature Profile CosTorus rPET has a slightly lower melting point than virgin PET due to the presence of recycled chain fragments. | Zone | Temperature (°C) | Notes | | :--- | :--- | :--- | | **Feed Throat** | 50 – 70 | Cooled to prevent bridging. | | **Zone 1 (Compression)** | 260 – 270 | | | **Zone 2 (Metering)** | 270 – 280 | | | **Zone 3 (Metering)** | 275 – 285 | | | **Adapter** | 270 – 280 | | | **Die** | 265 – 275 | Maintain even die temperature. | **Key Point:** Run the barrel temperature 10-15°C cooler than virgin PET to minimize thermal stress and degradation of the recycled polymer. ### 4.3 Screw Design Use a **general-purpose (GP) screw** with a compression ratio of 2.5:1 to 3.0:1. A mixing section (e.g., Maddock or Saxton) is recommended to ensure homogeneity of the recycled melt. Avoid high shear screws designed for virgin PET, as they can cause excessive shear heating and gel formation. ### 4.4 Melt Filtration - **Screen Packs:** Use 60/80/100 mesh (coarse to fine). - **Change Frequency:** Monitor pressure rise. Replace screens when back-pressure increases by 20% over baseline. - **Continuous Filtration:** For high-volume production, use a continuous screen changer (e.g., Beringer) with 40-micron filter elements. ### 4.5 Sheet Take-Off and Cooling - **Chill Roll Temperature:** 15°C – 25°C. - **Air Knife:** Use an air knife to pin the sheet to the chill roll, improving heat transfer and reducing haze. - **Drawdown Ratio:** Maintain a draw ratio of 1.5:1 to 2.5:1. Higher ratios can cause orientation and warpage. ### 4.6 Troubleshooting Common Defects | Defect | Cause | Solution (CosTorus) | | :--- | :--- | :--- | | **Black Specks / Gels** | Contamination or thermal degradation. | Reduce barrel temp by 5°C. Check screen packs. Ensure drying. | | **Sheet Sag / Draw Resonance** | Low IV or high melt temperature. | Increase IV grade (use EX-500). Lower die temp. Check drying. | | **Haze / Crystallization** | Slow cooling or high die temp. | Increase chill roll cooling. Reduce die temp. | | **Die Lip Build-up** | Volatiles or degraded polymer. | Increase vent vacuum. Reduce residence time. | --- ## 5. Certifications and Compliance For procurement engineers, certifications are the gatekeeper to market entry. CosTorus rPET holds several key certifications that de-risk its use in **rPET extrusion sheet film packaging**. ### 5.1 Food Contact Compliance - **EU Regulation 10/2011 (Plastic Materials and Articles):** CosTorus is compliant for food contact when used in a functional barrier layer or as a direct food contact material (subject to migration testing limits). - **FDA 21 CFR 177.1630:** The material meets requirements for food contact under Conditions of Use B-H (hot fill to frozen storage). - **EFSA Opinion (2020):** The European Food Safety Authority has published positive opinions on the use of rPET in food contact, provided it meets specific decontamination efficiency (e.g., Challenge Test) [EID-PIR-003]. ### 5.2 Recycled Content Certification - **ISCC PLUS (International Sustainability and Carbon Certification):** CosTorus is certified under the mass balance approach, ensuring traceability of recycled content throughout the supply chain. - **Global Recycled Standard (GRS):** The material is GRS-certified, confirming the recycled content percentage (typically 95-100% for PIR grades). ### 5.3 Quality Standards - **ASTM D7611 (Resin Identification Code):** CosTorus carries the #1 (PETE) RIC code. - **ISO 9001:2015:** Topcentral's manufacturing facilities are ISO 9001 certified for quality management. ### 5.4 End-of-Life Considerations - **Recyclability:** CosTorus rPET is fully recyclable in existing PET recycling streams (bottle-to-bottle or bottle-to-sheet). It does not introduce contaminants that would disrupt the recycling process. - **Biodegradation:** Standard PET does not biodegrade in landfill. However, the use of rPET reduces the need for virgin material, lowering the overall environmental burden. --- ## 6. Market Analysis: Cost, Supply, and Sustainability ### 6.1 Cost Comparison The cost of **rPET extrusion sheet film packaging** is volatile but generally follows virgin PET with a slight premium or discount depending on quality. | Material | Price (USD/tonne, Q4 2023 Estimate) | Volatility | | :--- | :--- | :--- | | **Virgin PET (Bottle Grade)** | $1,100 – $1,300 | High (linked to oil) | | **Standard PCR rPET (Loose)** | $900 – $1,100 | Moderate | | **CosTorus EX-500 (Pellets)** | $1,050 – $1,250 | Low (stable feedstock) | *Source: Plastics News, ICIS Pricing, Topcentral internal data.* **Warning:** Prices are indicative and subject to change. Contact Topcentral for current pricing. **Value Proposition:** While CosTorus may have a slight premium over loose PCR rPET, the reduction in scrap rate (up to 10%) and elimination of additive costs (toner, chain extenders) often results in a lower total cost of ownership (TCO). ### 6.2 Supply Chain Security Topcentral operates a vertically integrated supply chain, sourcing post-industrial scrap from certified partners. This ensures: - **Consistent Quality:** No batch-to-batch variation typical of municipal curbside PCR. - **Traceability:** Full chain of custody from scrap generator to finished pellet. - **Volume:** Guaranteed supply for large-scale packaging operations. ### 6.3 Carbon Footprint Using CosTorus rPET instead of virgin PET reduces the carbon footprint by approximately 50-70%, depending on the source of the scrap and the energy mix of the recycling facility [EID-PIR-004]. | Impact Category | Virgin PET (1 kg) | CosTorus rPET (1 kg) | Reduction | | :--- | :--- | :--- | :--- | | **Global Warming Potential (GWP)** | 2.5 – 3.0 kg CO2e | 0.8 – 1.2 kg CO2e | ~60% | | **Fossil Fuel Depletion** | 80 MJ | 20 MJ | ~75% | *Source: Life Cycle Assessment (LCA) data based on PlasticsEurope Eco-profiles and Topcentral internal calculations.* --- ## 7. Conclusion The transition to a circular economy for plastics is no longer optional—it is a regulatory and commercial imperative. For the **rPET extrusion sheet film packaging** sector, the technical barriers of IV drop, contamination, and aesthetic defects have historically limited recycled content usage. **CosTorus rPET from Topcentral** effectively solves these problems. By utilizing a high-quality PIR feedstock, advanced SSP technology, and rigorous quality control, it offers: - **Drop-in Processing:** IV values (0.72 – 0.82 dl/g) that mimic virgin PET. - **High Clarity:** L* > 85, haze < 2.5%. - **Full Certification:** ISCC PLUS, FDA, EU 10/2011 compliant. - **Economic Viability:** Reduced scrap rates and TCO. For procurement engineers, specifying CosTorus EX-500 or EX-700 is a low-risk, high-impact decision. For product designers, it enables the creation of sustainable packaging without compromising on performance. **Recommendation:** Request a trial batch of CosTorus rPET for your next extrusion project. Evaluate the material on your existing line with minimal adjustments to the temperature profile and screw design. --- ## 8. References [EID-PIR-001] European Commission. (2022). *Proposal for a Regulation on Packaging and Packaging Waste (PPWR)*. Brussels. Retrieved from [https://environment.ec.europa.eu/topics/waste-and-recycling/packaging-waste_en](https://environment.ec.europa.eu/topics/waste-and-recycling/packaging-waste_en) [EID-PIR-002] Welle, F. (2011). "Twenty years of PET bottle-to-bottle recycling—An overview." *Resources, Conservation and Recycling*, 55(11), 865-875. DOI: 10.1016/j.resconrec.2011.04.009. (Discusses gel count and contamination in rPET). [EID-PIR-003] EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP). (2020). "Safety assessment of the process ‘PETCYCLE’ used to recycle post-consumer PET into food contact materials." *EFSA Journal*, 18(6), e06156. Retrieved from [https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2020.6156](https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2020.6156) [EID-PIR-004] PlasticsEurope. (2022). *Eco-profiles and Environmental Product Declarations of the European Plastics Manufacturers*. Brussels: PlasticsEurope. (Provides LCA data for virgin PET and rPET). [EID-PIR-005] ASTM International. (2020). *ASTM D7611 / D7611M-20: Standard Practice for Coding Plastic Manufactured Articles for Resin Identification*. West Conshohocken, PA: ASTM International. [EID-PIR-006] Topcentral. (2023). *CosTorus EX-500 Technical Data Sheet*. Internal Document. [EID-PIR-007] Hopewell, J., Dvorak, R., & Kosior, E. (2009). "Plastics recycling: challenges and opportunities." *Philosophical Transactions of the Royal Society B: Biological Sciences*, 364(1526), 2115-2126. DOI: 10.1098/rstb.2008.0311. (General context on plastic recycling challenges). --- **Disclaimer:** The information provided in this article is for general informational and educational purposes only. It is not a substitute for professional engineering advice. Always conduct your own trials and due diligence before specifying materials for production. Performance data is based on standard test conditions and may vary with specific processing equipment and conditions.