Product Description

Ideal Plastic is a professional Vespel SP-22 Rods factory. SP-22 polyimide rod is a specialized composite polyimide material reinforced with a high 40% graphite filler ratio. The high-concentration graphite structure drastically suppresses thermal expansion and cold contraction, solving the common defect of dimensional deviation in engineering plastics under alternating hot and cold environments. While most modified PI materials prioritize wear resistance, SP-22 focuses on long-term dimensional accuracy and structural stability under continuous high-temperature and high-load operation.

Product Manufacturing Process

Manufactured through strict compression molding technology, SP-22 features uniform molecular density, low internal stress, and excellent anti-creep performance. Even after millions of cyclic loads and long-term high-temperature aging, the material maintains stable structural geometry. For industrial applications requiring zero-deformation precision, anti-radiation reliability, and high-insulation properties, SP-22 polyimide rod serves as an ideal semi-finished blank for custom precision machining.

Ideal Plastic specializes in custom compression molding of high-graphite polyimide profiles. With independent mold development capabilities and a complete precision processing system, we support both standard stock rods and custom-sized profile production, helping manufacturers obtain high-precision PI parts that meet strict environmental tolerance requirements.

Product Dimension & Specification Parameters

Product name	Vespel SP-22 Rods
Material	Polyimide resin powder with 40% graphite filler
Color	black
Dia	5-150mm
Length	1000mm
Tolerance	±0.02mm
sample	Negotiation
Minimum order quantity	1 piece
Certificates	ISO9001:2008： SGS RoHS： REACH
Additional services	Secondary processing can be provided.

Functional Characteristics of 40% Graphite Filled PI

1. Ultra-Low Thermal Expansion & Extreme Dimensional Stability

Benefiting from a highly ordered graphite molecular structure, SP-22 achieves one of the lowest thermal expansion rates among all commercial polyimide grades. It maintains stable size and geometric accuracy under drastic temperature changes, high heat, and humid working conditions. This characteristic effectively eliminates component jitter, positioning deviation, and assembly failure caused by material thermal deformation, perfectly matching high-precision industrial equipment standards.

2. Superior Electrical Insulation

The rigid aromatic heterocyclic molecular structure of SP-22 provides stable insulation performance. Internal hydrogen bonding and π-π stacking limit molecular displacement and electron migration, delivering a volume resistivity higher than 10¹⁶ Ω·cm. Even after long-term high-temperature operation, the material retains stable dielectric properties, avoiding insulation breakdown and leakage current risks in microelectronic components.

3. Exceptional Radiation Resistance

SP-22’s unique conjugated molecular system can absorb and disperse radiation energy efficiently. The 3D cross-linked molecular barrier prevents structural damage caused by high-dose radiation, enabling the material to retain complete mechanical and dimensional stability in radiation-intensive working environments, far exceeding the durability of ordinary engineering plastics.

4. Reliable Corrosion & High-Temperature Steam Resistance

This graphite-filled polyimide resists most conventional organic solvents and dilute acid corrosion. It can withstand long-term boiling environments at 120°C and maintain stable physical properties in high-temperature steam and concentrated sulfuric acid media. It is specially developed for harsh chemical and thermal cycle working conditions.

5. Excellent Fatigue & Creep Resistance

After millions of repeated mechanical shocks and cyclic loads, SP-22 retains more than 90% of its original mechanical strength. Its high-temperature creep resistance is significantly better than POM, PA, and PEEK, ensuring long-term operational stability of precision structural parts under sustained heavy loads.

6. Stable Self-Lubricating Property

High-density graphite forms a uniform protective lubricating layer on the material surface. With ultra-low surface energy (20-30 mN/m), Vespel SP-22 Rods effectively reduce friction adhesion and wear loss. It supports long-term dry friction operation without additional lubrication, adapting to high-speed and high-pressure mechanical motion scenarios.

Material Strengths & Practical Application Constraints

Core Strengths

Industry-leading low thermal expansion, ensuring micron-level dimensional stability under temperature alternation
Strong anti-creep performance, suitable for long-term fixed-load precision structural parts
Excellent radiation resistance, applicable for aerospace and special environmental equipment
Stable insulation performance, ideal for microelectronics and chip packaging components
Long fatigue life, reducing replacement frequency of cyclic moving parts

Practical Application Limitations

Not compatible with strong oxidizing media; prolonged exposure will cause molecular aging and performance attenuation
High graphite content leads to slight water absorption in extreme humid environments, which may cause tiny dimensional changes
Not recommended for ultra-high insulation scenarios requiring zero conductive filler contamination

Material Grade Comparison: SP-22 VS mainstream Industrial Plastics

Comparison Item	SP-22 (40% Graphite PI)	SP-211 (Graphite+PTFE PI)	Unfilled Pure PI	PEEK	Pure PTFE
Filler Feature	High graphite for stability	Dual filler for friction reduction	No filler	Mechanical optimization	Pure resin
Thermal Stability	Excellent (lowest expansion)	Very Good	Good	Medium	Poor
Dry Friction Performance	Good	Excellent	Average	Good	Excellent
High-Temp Creep Resistance	Top-tier	Strong	Strong	Normal	Weak
Best Application	Precision & dimensional stability parts	Heavy-load sliding friction parts	High-insulation electronic parts	General structural parts	Low-load sealing parts

Applicable Industrial Scenarios

SP-22 polyimide rods are exclusively selected for high-precision, high-stability industrial scenarios that forbid dimensional deformation:

Semiconductor & microelectronics: chip passivation layers, dielectric films, interlayer insulation, precision jigs and fixtures
Aerospace radiation-resistant structural components
High-temperature stable precision positioning parts
Cyclic moving parts requiring long-term fatigue resistance
Anti-corrosion and high-insulation industrial components

Precision Machining & Customized Technical Solutions

We provide one-stop precision processing services for SP-22 polyimide rods. Supporting full-format drawing customization, reverse engineering sampling, four-axis and five-axis CNC precision milling, laser cutting and fine polishing. All finished parts can reach assembly-level precision, eliminating secondary calibration for customers.

Factory Advantages

Specialized PI Molding Orientation: We focus exclusively on compression molding of high-graphite filled polyimide materials, rather than general plastic processing. All production and R&D resources are targeted at high-stability precision polymer materials for high-end industrial scenarios.
Independent Core Process R&D: Boasting 14+ years of specialized polyimide production experience, we have independently optimized exclusive molding processes for 40% graphite-filled SP-22 grade, effectively solving common industry defects such as uneven density and residual internal stress.
Complete Supporting Production System: Equipped with dedicated PI compression molding lines, professional precision testing instruments and advanced multi-axis CNC workshops. The whole industrial chain is self-controlled to stabilize overall production quality.
High-End Industry Service Experience: Long-term serving precision manufacturing fields including semiconductors, aerospace and new energy equipment, with mature production standards matching harsh and high-precision working requirements.
Diversified Production Flexibility: Possess flexible production capacity covering small-batch prototype trial production and large-scale mass orders, adapting to diverse procurement cycles of global industrial customers.
Standardized Global Service System: With long-term overseas service experience, we provide standardized material solutions and stable supply services for Europe, America, Southeast Asia and other global markets.

Guangzhou Ideal Plastic Technology Co., Ltd.

Exclusive Advantages of Our Custom SP-22 Rods

Fixed High-Purity Graphite Formula: Adopts stable 40% high-purity graphite filling ratio with strictly controlled ingredient proportion, ensuring consistent material compactness and zero dimensional deviation across different batches.
High-Density Compression Molding Craft: Our Vespel SP-22 Rods adopt professional compression molding technology, which delivers higher material compactness than conventional extrusion process, greatly boosting high-temperature creep resistance and cyclic fatigue resistance of SP-22 rods.
Ultra-Low Deformation Precision Control: Strictly eliminates internal residual stress during molding process, guaranteeing long-term geometric stability of precision parts under temperature alternation and continuous load operation.
Ultra-Low Threshold Procurement Support: Supports 1-piece MOQ for raw rod blanks, facilitating customers’ prototype verification, laboratory testing and small-batch project trial operation.
One-Stop Custom Processing Service: Provides full-link services from standard rod supply to finished precision CNC parts, saving customers secondary processing costs and procurement cycles.
Strict Batch Quality Inspection: Implements full-process sampling and performance testing for each batch of products, supporting long-term stable batch delivery for high-precision equipment manufacturing.

FAQ

1. What is your Vespel SP‑22 rod made of?

Our Vespel SP‑22 rod is polyimide resin powder filled with 40% graphite, and the color is black. It is manufactured by mold compression molding. We have hundreds of existing PI profile molds. If your required size matches our existing molds, we can shorten production lead‑time and save mold‑opening costs.

2. What are the dimensions and tolerance of SP‑22 rods?

Diameter range: 5‑150 mm
Standard length: 1000 mm
Dimensional tolerance: ±0.02 mm

3. What are the main properties of your SP‑22 polyimide rod?

Extremely low thermal expansion, stable dimension under high‑temperature and humid conditions
Excellent insulation: volume resistivity over 10¹⁶ Ω·cm
Outstanding radiation resistance
Good corrosion resistance: insoluble in common solvents, resistant to dilute acid; withstands 120 ℃ boiling for 500 hours, stable in high‑temperature steam; not suitable for strong oxidizing agents
Superior fatigue resistance: retains more than 90% strength after millions of stress cycles, outperforming typical engineering plastics such as POM
Self‑lubricating performance, low surface energy (20‑30 mN/m), low adhesion and wear
Good creep resistance under high‑temperature and heavy‑load working conditions

4. Where can SP‑22 graphite‑filled polyimide rods be applied?

Microelectronics & chip packaging: stress‑relief protective coatings, inter‑layer insulation, dielectric thin films, chip passivation layers
Harsh‑environment components requiring corrosion resistance and radiation resistance
Self‑lubricating sliding parts for dry or oil‑lubricated conditions
High‑speed and high‑pressure moving components
High‑strength structural parts with good tensile, bending and impact performance

5. Do you provide secondary machining services? What drawing formats do you accept?

Yes, secondary processing is available.
We accept drawings in STEP, STP, STL, IGS, IGES, PRT, SLDPRT, SAT, X_T formats. We can also develop products according to customer‑provided physical samples.

6. What is the MOQ for SP‑22 rods?

For semi‑finished SP‑22 rod blanks, the minimum order quantity is 1 piece.
For custom‑machined finished parts, MOQ will be negotiated according to processing technology and product dimensions.

7. Can I get SP‑22 samples for performance testing?

Free samples are available for in‑stock semi‑finished profiles; customers only bear the shipping cost.
Mass‑production products are guaranteed to match sample performance. Sample details need further negotiation.

8. What certifications do your SP‑22 rods have?

ISO9001:2008, SGS, RoHS and REACH compliance.

9. What are your payment terms?

A deposit is required before production starts. The balance shall be paid after production completion. We arrange shipment upon receipt of the full balance.

Payment can be made to our HSBC Hong Kong bank account or via your designated freight forwarder.

10. What is your lead time?

Stock‑available items will be shipped once payment is received.

Lead‑time for custom orders depends on order quantity and production process, which needs to be confirmed case‑by‑case.

11. What packaging options are available?

Cardboard box packaging, pallet packaging and customized packaging are supported.

12. Which logistics can you use for delivery?

We commonly use DHL, FedEx for air or sea shipment. Customer‑appointed logistics providers or freight forwarders are acceptable. All logistics costs are borne by customers.

13. What is your return and exchange policy?

‑ If quality problems are caused by our side: after verification, we will arrange refund or replacement and cover the related freight cost.

‑ If return is caused by customer‑side reasons (e.g. wrong ordering), returns are acceptable only when goods remain resalable; the customer shall take charge of return freight.

14. Can you sign a confidentiality agreement for my drawings?

Yes. We can sign a confidentiality agreement for customer‑provided drawings or product images. We will not publish or share your confidential information with third‑parties and take corresponding legal responsibility for breach.

15. Could you supply DuPont genuine Vespel raw material COA, complete quantitative datasheet or third‑party test report?

Please contact us for more details.

16. What about technical support such as machining parameters or bearing design suggestions for SP‑22?