PetroChina Fushun Petrochemical Co., Ltd.

The polypropylene homopolymer pellet stream from PetroChina Fushun Petrochemical Co., Ltd. is converted on high-speed three-layer BOPP tenter lines running at 250 m/min to 450 m/min. The core layer uses a high-isotacticity PP homopolymer with an isotactic index of 95% to 98%, a melt mass-flow rate of 2.5 g/10 min to 4.0 g/10 min at 230 °C/2.16 kg per ISO 1133-1:2022, and a gel defect level below 100 ppm. Coextrusion is carried out through a 2.0 mm to 2.4 mm die gap with melt temperatures held between 230 °C and 250 °C. The cast sheet is quenched on a chill roll maintained at 20 °C to 30 °C. Quench temperature controls the mesomorphic content of the sheet and directly affects transverse stretchability. Machine-direction orientation is applied at 4.5:1 to 5.5:1, followed by transverse stretching at 7:1 to 10:1 in a tenter oven with zone temperatures between 150 °C and 165 °C. Film haze per ASTM D1003-21 is commonly specified at 1.0% to 2.5% for corona-treated transparent grades. Tensile strength per ISO 527-3:2018 ranges from 120 MPa to 180 MPa in the machine direction and from 220 MPa to 300 MPa in the transverse direction for film gauges of 18 µm to 40 µm. The main process conflict occurs at the chill roll and die lip. Low-molecular-weight fractions in the Fushun pellet stream can accumulate on the die lip after 6 h to 12 h of continuous operation, forcing line stops when deposit thickness exceeds 0.3 mm. Chill roll surface roughness above 0.2 µm Ra is correlated with line speed loss of 10% to 20% because of reduced melt bank stability. Transparent BOPP production therefore requires additive packages that neutralise peroxide residues and acid species without increasing surface haze or plate-out.

What Limits Injection Moulding Cycle Time in Thin-Wall Food Containers?

The limiting variable in thin-wall polypropylene food containers with wall sections of 0.4 mm to 0.8 mm is not peak hydraulic pressure but the relationship between melt mass-flow rate, gate freeze-off time, and sink mark formation. A PP homopolymer stream from PetroChina Fushun Petrochemical Co., Ltd. with melt mass-flow rate of 25 g/10 min to 45 g/10 min per ISO 1133-1:2022 is processed on hybrid injection moulding machines with clamp forces from 150 t to 500 t. Melt temperatures are held at 220 °C to 250 °C and mould temperatures at 20 °C to 40 °C. Injection speed is set at 150 mm/s to 300 mm/s. Fill time below 0.5 s is required when the flow length to wall thickness ratio exceeds 150:1. At an MFR above 35 g/10 min, the hold-pressure window narrows to approximately ±5 MPa. Screw tip pressure variation of ±2 bar on high-cavitation tooling can shift part mass by 0.8% to 1.5%. The gate freeze-off time is typically below 1.2 s for pin gates of 0.8 mm to 1.2 mm diameter. Cycle time is therefore constrained more by mould temperature stability and part ejection than by material solidification alone. Differential shrinkage between flow direction and transverse direction generates warpage in flat lids. Unfilled PP homopolymer exhibits shrinkage of 1.0% to 1.5% in the flow direction and 0.8% to 1.2% transverse when measured per ISO 294-4:2018. A nucleated PP formulation can reduce haze and improve heat deflection temperature. Heat deflection temperature per ISO 75-2:2013 method B is typically 80 °C to 100 °C at 0.45 MPa. Published data for the precise crystallisation half-time of the Fushun thin-wall grades is limited. The available processing data indicate that mould temperatures above 40 °C reduce sink mark depth but extend cycle time by 3 s to 8 s depending on part thickness.

In spunbond nonwoven production for disposable medical gowns and hygiene outer sheets, the PP homopolymer stream from PetroChina Fushun Petrochemical Co., Ltd. is metered into single-screw extruders with L/D 30:1 and a barrel temperature profile from 200 °C in the feed throat to 245 °C at the melt pump. The melt is distributed through spinnerets with hole diameters of 0.4 mm to 0.6 mm. Quench air is supplied at 15 °C to 25 °C with an air velocity of 0.4 m/s to 0.8 m/s. Filament drawing uses slot-jet or apron exhaust systems with air pressure of 1.5 bar to 3.5 bar. Resulting as-spun filament diameters are 15 µm to 25 µm. The web is calendered at 145 °C to 165 °C with nip line pressure of 40 N/mm to 80 N/mm. Fabric tensile strength for a 25 g/m² web is assessed by NWSP 110.4-09 or ISO 9073-3:2023. Typical machine direction strip tensile is 20 N/5 cm to 35 N/5 cm. Hydrostatic head for a standard spunbond layer is 200 mm H₂O to 400 mm H₂O. This does not provide a standalone barrier claim. Medical gowns require an additional meltblown layer to meet EN ISO 13795-1:2019. The critical processing bottleneck occurs at the spin pump and spinneret pack. Melt pressure fluctuation above ±5 bar causes filament denier variation of ±10% to ±15%, reducing web uniformity and creating soft spots after hot calendering. Spin filter pack life is typically 48 h to 96 h for the Fushun resin stream. Gel particles above 50 particles/m² in 12 µm cast film are associated with a shorter pack life and increased spinneret hole blockage.

When Mineral-Filled Polypropylene Replaces Engineering Thermoplastics in Automotive Interior Structural Brackets

Compounding of 20 wt% to 40 wt% finely milled talc into the PP homopolymer stream from PetroChina Fushun Petrochemical Co., Ltd. is performed on twin-screw extruders with L/D 40 to 44. Filler is introduced by side feeding at melt temperatures of 200 °C to 230 °C. A maleic anhydride grafted PP coupling agent at 1.0 wt% to 2.0 wt% is added to shift tensile modulus from 1300 MPa to 2500 MPa depending on talc median particle size of 1.5 µm to 5.0 µm. Notched Izod impact strength per ISO 179-1:2023 at 23 °C remains 2.5 kJ/m² to 4.5 kJ/m². Heat deflection temperature per ISO 75-2:2013 method B rises to 75 °C to 105 °C. The weld-line region in talc-filled PP is the primary failure site in brackets with complex rib patterns. Filler platelets orient parallel to melt flow. Across the weld face, orientation becomes transverse and local tensile strength drops by 20% to 35% relative to the bulk. Sequential valve-gate control reduces weld-line width, but the central weld zone remains the lower-strength region. Injection-moulded parts are conditioned and tested under VDA 277 for total volatile organic compound emissions, with a common acceptance threshold below 50 µg/g. Fogging is tested per DIN 75201-B, with condensate below 2 mg. Odour score per VDA 270-A is not higher than 3. Shrinkage anisotropy measured per ISO 294-4:2018 is 0.6% to 1.0% in the flow direction and 0.8% to 1.2% transverse. Brackets longer than 300 mm show measurable warpage unless tool cooling is balanced to within ±5 °C. Published data for ageing retention of the Fushun PP stream in talc-filled automotive interior configurations is limited. The available process data indicate that excessive shear during compounding above 600 rpm screw speed can break the talc platelets and reduce modulus gain by 10% to 15%.

PP-R Pipe Extrusion: Fusion Integrity and Hydrostatic Design Basis

For PP-R hot- and cold-water pipe extrusion, the propylene-ethylene random copolymer stream associated with PetroChina Fushun Petrochemical Co., Ltd. requires a melt mass-flow rate of 0.25 g/10 min to 0.45 g/10 min per ISO 1133-1:2022. Processing is carried out on grooved-barrel single-screw extruders with L/D 30:1 to 33:1. Barrel zones are held at 190 °C to 230 °C, with the die head below 210 °C to avoid surface degradation. Pipe dimensions follow ISO 15874-2:2013. Hydrostatic tests are carried out per ISO 1167-1:2006 at 20 °C/1 h, 95 °C/22 h, and 95 °C/1000 h. The resin must maintain an oxidation induction time at 210 °C greater than 20 min per ISO 11357-6:2021 to support hot-water performance expectations. At die exit temperatures above 215 °C, the melt exhibits low melt tension and pipe wall eccentricity exceeds ±0.2 mm on diameters above 110 mm. Cooling water at 20 °C to 40 °C can induce residual stress. Stress-relief annealing at 80 °C for 2 h reduces longitudinal shrinkage measured per ISO 2505:2023. Published hydrostatic failure data for Fushun PP-R grades in English-language peer-reviewed literature is limited. The design values cited derive from ISO 15874:2013 reference curves for propylene random copolymers with MFR of 0.25 g/10 min to 0.45 g/10 min. Long-term creep resistance is evaluated at 70 °C under hydrostatic design stress of 3.2 MPa to 3.5 MPa. Pipe fusion integrity is checked by socket fusion at 260 °C to 270 °C; overheating above 275 °C produces a visible melt bead defect and reduces fusion joint strength.

A Low-Denier Fibre Grade Processes Well on High-Tenacity Warp Drawing Lines

For cement fibre reinforcement, polypropylene staple fibre spun from the Fushun PP homopolymer stream is extruded at melt temperatures of 220 °C to 240 °C, quenched in air, and drawn in a two-stage hot air oven at 120 °C to 160 °C with a total draw ratio of 6:1 to 8:1. Resulting fibre linear density is 2.2 dtex to 6.7 dtex and cut length is 6 mm to 12 mm for mortar admixture. Alkali resistance is assessed by weight loss after immersion in 1 M NaOH at 80 °C for 24 h. Unmodified PP fibre shows mass loss below 0.5%. The fibre does not contribute to corrosion of reinforcement steel. Overdrawing above 8:1 at oven temperatures below 120 °C causes fibrillation and reduces fibre tenacity below 4 cN/dtex. Spin finish selection controls static charge generation. Without an antistatic package, carding line speed is typically limited to 80 m/min to 100 m/min before cylinder loading occurs.