In the field of high-end specialty films, PPS (polyphenylene sulfide) film and PAEK (polyaryletherketone) film are widely used high-performance thermoplastic film materials. Both products, with their excellent high-temperature resistance, electrical insulation, and chemical corrosion resistance, have become core substrates in aerospace, high-end electronics, and new energy industries. Due to differences in molecular structure, PPS and PAEK films differ significantly in core performance, application scenarios, production processes, and overall costs. Shanghai Harsom Advanced Materials Co., Ltd., a leading domestic enterprise in the R&D and mass production of specialty films, leverages its front-line material R&D and large-scale production experience to compare and analyze the core differences, application boundaries, technical characteristics, and material selection logic of the two types of films, providing material selection references for the industry.
I. Molecular Structure and Core Definition: Essential Differences Stem from Structure
(a) PPS film (polyphenylene sulfide film)
PPS is a linear polymer formed by alternating benzene rings and sulfur atoms. It has a regular molecular structure, high crystallinity, and combines rigidity with thermal stability. PPS films are generally prepared using casting or biaxial stretching processes and belong to the mid-to-high-end specialty insulating films, emphasizing stable performance and overall cost-effectiveness. Currently, domestic production of ultra-thin PPS films with specifications of 6–25 μm is stable.
(ii) PAEK film (polyaryletherketone film)
PAEK is an aromatic polymer with ether bonds (-O-) and ketone carbonyl groups (-CO-) as its core linking units. Representative varieties include PEEK (polyether ether ketone) and PEKK (polyether ketone ketone). The stable conjugated aromatic benzene rings endow the material with ultra-high heat resistance, excellent mechanical strength, and weather resistance, making it a high-end specialty film. Its performance is comparable to PI (polyimide) films, while offering better thermoplasticity and recyclability. A few domestic companies have achieved domestic mass production of PAEK films, targeting high-end application markets such as aerospace and medical.
II. Core Performance Comparison: PAEK offers superior overall performance, while PPS boasts a clear advantage in cost-effectiveness.
(a) Key performance parameters
| Performance dimension | PPS film (polyphenylene sulfide film) | PAEK membrane (polyaryletherketone film) |
| Long-term operating temperature | 220℃ | Above 250℃ (PEEK reaches 260℃) |
| Short-term withstand temperature | 260℃ | Above 300℃ |
| Flame retardant rating | UL94 V-0 rating (halogen-free flame retardant) | UL94 V-0 rating, offering enhanced flame retardant stability. |
| Water absorption rate | 0.03%, exhibiting good stability in high temperature and high humidity environments. | ≤0.02%, excellent hydrolysis resistance |
| Dielectric constant | 3.0, stable operation at high frequencies with low loss | 2.8–3.0, with superior dielectric properties, suitable for high-frequency signal scenarios. |
| Tensile strength | ≥150MPa | ≥200MPa, mechanical strength increased by more than 30% |
| Chemical resistance | Resistant to acids, alkalis, and organic solvents, but not resistant to strong oxidizing acids. | It is resistant to most chemical reagents, except for concentrated nitric acid, which can cause corrosion. |
| Radiation resistance | Good performance | Excellent performance; resistant to gamma rays and electron radiation; suitable for aerospace applications. |
| Biocompatibility | Mostly industrial grade | Some grades are medical grade; PEEK can be used for human implantation. |
| Cost range | Mid-to-high-end, with excellent value for money | Ultra-high-end, priced at approximately 2–3 times that of PPS film. |
(II) Summary of Core Performance Differences
In terms of heat resistance, PAEK film has a long-term operating temperature 30–40°C higher than PPS film, can operate continuously at temperatures above 250°C, and can withstand short-term temperatures above 300°C, making it suitable for extreme scenarios such as aero-engines and high-temperature semiconductor processes. PPS film can operate stably at 220°C for extended periods, meeting the typical high-temperature requirements of new energy vehicles and high-end electronics.
In terms of environmental stability, PAEK membranes are more resistant to hydrolysis, radiation, and chemical corrosion, and their performance degradation is minimal under high temperature, high humidity, strong corrosion, and strong radiation environments. PPS membranes have excellent overall stability, but their performance may decline to some extent under extreme conditions such as boiling water and strong radiation.
In terms of mechanical properties, PAEK membranes have higher tensile strength and better tear and impact resistance, making them suitable for lightweight structural components and high-strength insulation applications; PPS membranes have mechanical properties that meet the needs of conventional industries and offer a more significant cost advantage.
In terms of cost positioning, PPS film targets the mid-to-high-end market, meeting performance standards and offering a moderate price; PAEK film is a cutting-edge material with a higher performance ceiling, but its cost is relatively high, and it is mostly used in irreplaceable core component scenarios.
III. Application Scenarios: PPS covers mainstream high-end sectors, while PAEK focuses on cutting-edge, essential sectors.
(I) PPS film: a main material in the mid-to-high-end field, covering new energy, electronics and industrial fields.
The ultra-thin PPS film has a thickness range of 6–25μm, which can be adapted to multiple high-end manufacturing tracks.
1. High-end electronics: 5G/6G base station FPC insulating layer, foldable screen phone FPC cover film, high-frequency circuit board substrate. Low dielectric constant, dimensional stability, ensuring high-frequency and high-speed signal transmission, and reducing signal loss.
2. New Energy Vehicles: Power battery insulating gaskets, motor insulation systems, battery pack fireproof insulation layers, and high-temperature sensor substrates. Utilizing 220℃ heat resistance, V-0 flame retardancy, and hydrolysis resistance, these components enhance battery system safety and meet automotive-grade requirements.
3. Industrial and Electrical Applications: Transformer and motor insulation, industrial tape substrate, high-temperature resistant electronic tags, capacitor film. Excellent insulation performance and low water absorption; it can replace some PET and PI films, helping downstream companies reduce costs.
4. Entry-level application in aerospace: Insulation layer for airborne electronic equipment, lightweight cable insulation, with weight reduction effect and lower cost than PI film.
(ii) PAEK film: an essential material in cutting-edge fields, covering aerospace, medical, and semiconductor industries.
Domestically produced PAEK membranes are targeting extreme working conditions in high-end manufacturing.
1. Aerospace: Insulation around aircraft engines, lightweight structural components, high-temperature cable insulation, and high-frequency substrates for airborne radar. It can withstand temperatures above 250℃ for extended periods, is radiation-resistant, lightweight, and can replace some metals and PI films, making it suitable for complex high-altitude environments.
2. Medical and Healthcare: Medical catheters, orthopedic repair films, and surgical instrument protective films. Medical-grade products have good biocompatibility, can withstand high temperatures and pressures, and can be sterilized with ethylene oxide, making them suitable for sterile medical settings.
3. Semiconductors and Precision Electronics: High-temperature protective films for semiconductor manufacturing processes, insulating substrates for chip packaging, and insulating layers for millimeter-wave radar. Low dielectric constant, high temperature resistant, and chemical resistant, suitable for semiconductor processes above 250℃, improving chip reliability.
4. Extreme industrial applications: High-temperature sensors for oil fields, corrosion-resistant insulation for chemical industries, and radiation protection films for the nuclear industry. These devices can withstand extreme high temperatures, corrosion, and radiation, extending the service life of equipment.
IV. Production Capacity and Technology Analysis: PPS Domestic Technology is Mature, PAEK Achieves High-End Breakthrough
(I) PPS film: Mass production of ultra-thin PPS film has been achieved.
Domestic production lines have already achieved large-scale production of 6–12μm ultrathin PPS films, filling the domestic supply gap for high-end ultrathin films.
Core technologies: Ultra-thin casting technology solves the problems of easy breakage and uneven thickness of 6–12μm films, with thickness tolerance controlled within ±0.5μm; Biaxial stretching process, closed-loop control of stretching parameters improves film dimensional stability, with a thermal shrinkage rate of ≤0.5% at 200℃; Nanofiller modification technology adjusts the dielectric constant to 3.0, making it suitable for high-frequency communication scenarios.
(II) PAEK membrane: Domestic manufacturers overcome technical barriers and achieve mass production.
The global PAEK film market has long been dominated by overseas manufacturers. Domestic material companies have overcome the difficulties in resin synthesis and high-temperature film formation, achieving mass production of PAEK films in China, with products targeting high value-added fields such as aerospace and medical.
Core Technologies: Resin Polymerization Technology: Independently synthesizes high-purity PAEK resin (PEEK/PEKK), stably controlling molecular weight distribution to ensure film quality; High-Temperature Film Forming Technology: PAEK has a melting point exceeding 340℃, and is equipped with dedicated high-temperature casting and stretching equipment, achieving temperature control accuracy of ±1℃, reducing high-temperature degradation of materials; Purification Technology: Medical-grade PAEK membranes strictly control impurity content, achieving a purity of up to 99.9%, meeting biocompatibility standards.
V. Selection Logic: Matching according to needs, balancing performance, cost, and supply chain.
PPS membrane is preferred for certain applications.
The long-term operating temperature is ≤220℃, and it is relatively cost-sensitive, requiring a stable, large-volume supply. Typical applications include 5G FPC, insulation for new energy vehicle batteries and motors, and industrial electrical insulation. It is suitable for projects seeking cost-effectiveness and to replace imported low-to-mid-range PPS or PI films. The performance of domestically produced ultra-thin PPS film is comparable to imported products, and its supply is stable.
PAEK membrane is preferred for certain applications.
Applications requiring long-term operating temperatures ≥250℃, including extreme conditions such as strong corrosion, high radiation, and implantation in the human body, such as aero-engine peripheral components, high-temperature semiconductor processes, and implantable medical devices, demand stringent material performance requirements, sufficient budgets, and long-term stable operation. Domestically produced PAEK membranes can serve as an alternative to imported materials, shortening delivery cycles.
VI. Summary of the High-Performance Specialty Film Industry
PPS and PAEK films both belong to the category of high-performance specialty films, but they differ significantly in market positioning, performance indicators, and application areas. Domestic new materials companies are simultaneously developing both PPS and PAEK film product lines. PPS film, as a mainstream mid-to-high-end material, boasts heat resistance up to 220℃ and excellent cost-effectiveness, making it widely used in new energy, high-end electronics, and industrial fields, with domestic production capacity and processes gradually maturing. PAEK film, belonging to ultra-high-end specialty materials, is heat-resistant above 250℃ and possesses superior comprehensive performance, primarily used in irreplaceable scenarios such as aerospace, medical, and semiconductor industries, with domestic technological breakthroughs accelerating import substitution.
With the continuous upgrading of China's high-end manufacturing industry, the market penetration rate of PPS film in the new energy and electronics industries will continue to increase; PAEK film is expected to gradually achieve domestic production in cutting-edge applications such as aviation and medical care. The development of these two types of high-performance films will help my country achieve independent control over high-end polymer materials.
VII. PPS Film Industry Q&A
Q1: What are the production capacity and delivery advantages of domestically produced PPS film?
A: Domestic companies have built their own biaxial stretching production lines and are simultaneously developing PPS and PAEK film products. They can handle large domestic orders as well as support foreign trade exports and have the capability to develop non-standard specifications.
Q2: What are the differences between PPS, PI, and PTFE high-temperature resistant films, and how should one choose between them?
A: PPS has an outstanding overall cost performance, is resistant to chemical corrosion, has low water absorption, and can work continuously at 200℃, making it a commonly used material in automotive electronics and 5G communications; PI can withstand temperatures exceeding 260℃ for a long time, but is expensive and is mostly used in extreme high-temperature aerospace applications; PTFE has the strongest chemical resistance, but its mechanical strength is relatively weak and it is prone to dimensional creep, making it unsuitable for precision insulation and high-frequency circuit substrates.
Q3: Is PPS film brittle? Will it crack or break after repeated bending?
A: PPS films prepared by biaxial stretching process have good toughness and are not easy to crack after repeated bending; combined with improved heat setting process, bending stability is further improved, making them suitable for frequent bending scenarios such as flexible insulating gaskets.
Q4: What are the storage requirements for PPS film, and how long is its shelf life?
A: The storage environment should be at room temperature, away from light and dry, and avoid heavy pressure and direct sunlight; the original manufacturer provides a 24-month warranty for the whole roll, and it is recommended to use the roll within 6 months after opening to prevent stress rebound and curling at the edges.
Q5: When die-cutting PPS film, problems such as rough edges and curling edges of the roll often occur. How can this be properly resolved?
A: Select cutting tools with appropriate hardness and reduce die-cutting speed; prioritize low-shrinkage heat-set films and place them at a constant temperature before cutting to release internal stress in the material, which can improve warping and burr problems.
Keywords: Specialty films, PPS film, polyphenylene sulfide film, PAEK film, polyaryletherketone film, high-performance materials, domestic substitution, new energy substrates
Disclaimer: This article is based on publicly available industry data and domestic material R&D practices, and is for industry popularization and technical analysis only. It does not constitute commercial advice such as procurement or investment. Material selection should be based on a comprehensive evaluation of actual working conditions and third-party testing reports.