The POLYfill PPC T1010 / T1020 / T1030 / T1035 PP Copolymer series is identified in supplier documentation as a polypropylene copolymer family. In industrial practice, PPC designations of this type commonly refer to heterophasic impact copolymers in which an ethylene-propylene rubber phase is dispersed in a polypropylene homopolymer matrix; however, the exact morphology, rubber content, and additive package must be confirmed from the grade-specific technical datasheet and certificate of analysis. Density under ISO 1183-1:2019 is typically 0.89–0.91 g/cm³ for unfilled PP impact copolymer. Melt mass-flow rate is the primary discriminator among the four T-suffix models and is determined at 230 °C with a 2.16 kg piston load under ISO 1133-1:2022. All numerical values in this introduction are class-level ranges for unfilled PP impact copolymers and do not replace lot-specific data.

The four models share the same unfilled copolymer backbone but are separated by melt flow and the resulting balance between processability and low-temperature toughness. The T1010, T1020, T1030 and T1035 suffixes are not trade names for separate chemistries; they indicate flow-grade differentiation within one family. Selection of the correct grade depends on wall thickness, flow length, mould temperature capability, impact requirement, and the desired cooling time.

How Are T1010, T1020, T1030, and T1035 Separated in Melt Rheology?

Model suffixes in this series are linked to nominal melt-flow targets in the supplier’s technical literature. The numerical suffix convention corresponds to nominal MFR values of 10 g/10 min for T1010, 20 g/10 min for T1020, 30 g/10 min for T1030 and 35 g/10 min for T1035 under ISO 1133-1:2022 at 230 °C and 2.16 kg. The actual lot value may vary within the supplier’s release window; the certificate of analysis remains the controlling value for machine setup.

From T1010 to T1035 the increase in MFR corresponds to a progressive reduction in zero-shear viscosity and in the pressure required to fill thin sections. The relationship is not linear: a nominal 3.5-fold increase in MFR does not produce a 3.5-fold reduction in injection pressure. Rheological comparison should be performed by capillary rheometry under ISO 11443:2021 at 230 °C across shear rates of 100 s⁻¹ to 1,000 s⁻¹, because the high-flow variants exhibit more pronounced shear-thinning. On a 1,200 kN injection moulding machine with a 0.8 mm hot-runner valve gate, T1035 typically fills a 2 mm plaque at a lower injection pressure than T1010, but the exact differential depends on gate freeze time, melt cushion stability, and mould temperature. Published data for this specific configuration is limited; therefore direct comparative moulding trials are recommended for pressure-drop calculation.

Mechanical property profiles of this family are governed less by the T-suffix than by the ethylene-propylene rubber content, the polypropylene matrix crystallinity, and the thermal history imposed during conversion. Under ISO 527-2:2012, class-level tensile yield stress for unfilled heterophasic impact copolymers generally falls between 22 MPa and 28 MPa, and tensile elongation at yield is typically 5–8%. Flexural modulus measured under ISO 178:2019 commonly lies in the 1,000–1,500 MPa range. Notched Charpy impact strength under ISO 179-1/1eA at 23 °C spans 8–25 kJ/m² for lower-MFR impact copolymers, while the same property at −20 °C is commonly 4–10 kJ/m². The T1035 high-flow grade tends to occupy the lower end of the low-temperature impact range because the reduced molecular weight and modified rubber particle size distribution accompanying higher flow can reduce energy absorption before brittle failure. The tensile modulus difference between T1010 and T1035 is small relative to the notched impact difference; therefore grade selection based solely on tensile datasheet values is insufficient for impact-critical parts.

Injection Moulding, Extrusion, and Compounding Boundaries

This series is processed on standard polyolefin injection moulding machines and single-screw extruders. The plasticating unit should provide a 24:1 to 30:1 L/D ratio and a 2.2:1 to 2.8:1 compression ratio. For T1010 and T1020, a general-purpose three-zone screw is adequate; for T1030 and T1035, a low-shear screw with a compression ratio below 2.5:1 reduces shear-induced overheating. Hydraulic clamp force from 500 kN to 25,000 kN covers the typical part-size range from closure tabs to appliance and automotive interior components; exact clamp force is calculated from the projected area multiplied by cavity pressure. A cavity pressure of 25–40 MPa is a normal target for PP impact copolymers in injection moulding.

Pre-drying is not normally required for pellets stored below 60% relative humidity. If pellets are transferred from cold storage to a warm production hall or if surface moisture exceeds 0.1% by mass, desiccant drying at 80 °C for 2–4 hours at a dew point of −30 °C or lower is sufficient. Barrel temperature profiles should be set between 220 °C and 250 °C from feed to metering. The melt temperature at the nozzle should not exceed 260 °C. Hot-runner manifolds should be controlled within ±5 °C of the nozzle melt temperature; larger deviations can shift filling balance in multi-cavity tools and create weld-line weakness.

Residence time at melt temperature should be limited to 10 minutes or less. Prolonged residence above 260 °C promotes chain scission, yellowing, and a measurable reduction in notched impact strength. When changing from T1010 to T1035, screw speed should be reduced by 10–20% if the same barrel profile is used because the high-flow grade generates less shear heating and may homogenize more quickly. For T1035, a shut-off nozzle is recommended on machines with open-nozzle configurations to prevent drool. Back pressure of 0.5–1.0 MPa hydraulic is typical for natural grades; colour concentrates may require a 20–30% increase in back pressure to ensure dispersion. These settings are starting points and should be adjusted using short-shot studies rather than fixed parameters.

Mould shrinkage measured on 60 mm × 60 mm × 2 mm plaques under ISO 294-4 is typically 1.1–1.4% parallel to flow and 1.2–1.6% transverse to flow for unfilled PP impact copolymer. Thicker sections above 4 mm may exhibit core voiding if the packing pressure is released before gate freeze; hold time should be extended until the gate seal time determined by weighing consecutively moulded parts. Cooling time for thicknesses above 3 mm can be approximated as 0.8–1.5 s/mm of wall thickness, but the exact value depends on mould temperature, coolant turbulence, and part stiffness at ejection.

When Low-Temperature Impact Resistance Governs Part Design

If the part is exposed to sub-zero impact during service, T1010 or T1020 is generally preferred over T1030 or T1035. Notched Charpy impact strength under ISO 179-1/1eA at −20 °C is a more discriminating test than room-temperature tensile yield stress for cold-climate automotive trims, appliance housings, or returnable logistics containers. Class-level values for heterophasic PP impact copolymers with nominal MFR below 20 g/10 min commonly fall between 5 kJ/m² and 10 kJ/m² at −20 °C, whereas high-flow variants above 30 g/10 min may fall below 4 kJ/m² in thick sections. The brittle-to-ductile transition is also influenced by part wall thickness, weld lines, and mould temperature; therefore pendant-impact data should be supplemented by falling-dart impact testing under ISO 6603-2:2017 or ASTM D3763-18 using the actual part thickness.

Higher mould temperatures of 50–80 °C improve the spherulitic morphology and weld-line strength in impact-critical parts. A mould temperature below 30 °C can produce a frozen skin layer that reduces the effective crack initiation energy. The lower-MFR T1010 grade often tolerates higher mould temperature without excessive sticking; the high-flow T1035 may require a shorter holding time to avoid sink marks and warpage. This interaction between mould temperature, cycle time, and impact retention is a primary process conflict in high-volume production.

Regulatory documentation for the POLYfill PPC series is grade- and formulation-specific. Polyolefin copolymers can be evaluated for food-contact use under FDA 21 CFR 177.1520 and European Union Regulation (EU) No 10/2011 when the additive package is compliant and no excluded substances are introduced during conversion. RoHS recast Directive 2011/65/EU Annex II restrictions for lead, mercury, cadmium, hexavalent chromium, PBBs, and PBDEs apply to finished articles only when they are placed on the EU market; material declarations should be requested from the supplier for each lot. REACH compliance is substance-specific and must be checked against the current ECHA candidate list. Extractives testing under EN 1186 or migration modelling under EU 10/2011 cannot be inferred from the polymer family alone and must be performed on the final component.

The MFR Increase from T1010 to T1035 Creates a Stiffness-Impact Trade-Off, Not a Uniform Property Upgrade

The copolymer phase in this series reduces tensile modulus and thermal deflection temperature relative to a PP homopolymer of equivalent MFR. Typical flexural modulus for impact copolymers is 1,000–1,500 MPa; homopolymers often exceed 1,500 MPa and may reach 1,800 MPa depending on nucleation and additive loading. Notched impact strength under ISO 179-1/1eA at 23 °C is usually higher by a factor of 2 to 5 compared with homopolymer. The same copolymer phase reduces optical clarity relative to random copolymers; haze measured under ASTM D1003 is higher because the dispersed rubber phase scatters light. This series is therefore not a direct substitute for random copolymer in translucent packaging or clear housewares. Published data for the specific light-transmission values of each T-suffix is limited; optical-grade substitution requires moulded plaque testing according to ASTM D1003 and ISO 14782:2021.

Compared with glass-fibre-reinforced PP, this unfilled series has lower tensile modulus and lower heat deflection temperature under ISO 75-2:2020, but it provides lower screw and barrel wear, lower anisotropy, and reduced visible glass-fibre orientation in the moulded surface. Compared with elastomer-modified polyolefin compound, the PP copolymer series retains higher crystallinity and a sharper solidification transition, which can reduce cycle time in injection moulding but lowers ultimate elongation after yield. These differences should be evaluated against the part’s functional requirements using minimum test methods such as ISO 527-2:2012, ISO 178:2019, ISO 179-1/1eA, and ISO 75-2:2020 Method A or B.