Plastic Screw & Fastener Material Guide: Lightweight, Heat & Chemical Resistant Solutions
This guide integrates technical references and practical application experience to systematically categorize plastic screws and fasteners into three major groups: High-Performance Engineering Plastics, Engineering Plastics, and Commodity Plastics.
The content focuses on key material selection factors—including heat resistance, mechanical strength, chemical resistance, electrical properties, and cost efficiency—to help users, engineers, and procurement professionals choose the most balanced and cost-effective material for different application environments.
Plastic Screw / Fastener Material Comparison Table
| Category | Material | Continuous Service Temperature | Key Advantages | Typical Applications | Limitations |
|---|---|---|---|---|---|
| High-Performance Engineering Plastics | PI (Polyimide) | ~260°C | Exceptional heat resistance, wear resistance, low outgassing in vacuum | Semiconductor vacuum fixtures, aerospace wear bushings, thermal insulation supports | Susceptible to hydrolysis in hot water/steam; poor resistance to strong acids and bases |
| PEEK (Polyether Ether Ketone) | ~240°C | High mechanical strength, broad chemical resistance, inherent flame retardancy (UL94 V-0) | Semiconductor equipment, chemical processing, aerospace components | High material cost | |
| PFA (Perfluoroalkoxy) | ~260°C | Ultra-high purity, chemically inert, injection-moldable | Semiconductor wet processes, ultra-pure chemical fluid systems | Lower mechanical strength than PEEK | |
| PTFE (Polytetrafluoroethylene) | ~260°C | Outstanding chemical resistance, ultra-low friction (self-lubricating), non-stick | Highly corrosive acid/alkali tanks, laboratory components requiring frequent assembly | Low rigidity, prone to cold flow; not recommended for dynamic or load-bearing applications | |
| PPS (Polyphenylene Sulfide) | ~200°C | High stiffness, inherent flame retardancy (V-0), excellent dimensional stability | Automotive engine compartments, electronic connectors, chemical pumps | Relatively brittle; avoid excessive impact during installation | |
| PEI (Polyetherimide) | 170–180°C | Excellent dimensional stability, high dielectric strength, flame retardant with better cost efficiency than PEEK | ATE test fixtures, power module backplates | Lower heat and chemical resistance compared to PEEK | |
| Engineering Plastics | PVDF (Polyvinylidene Fluoride) | ~150°C | High purity, resistant to halogens and strong acids, excellent UV and weather resistance | Ultra-pure water systems (RO), lithium battery manufacturing, outdoor equipment | Lower toughness than PEEK; avoid over-tightening |
| RENY (Glass-Fiber Reinforced Nylon) | ~105°C | Strength and stiffness close to metal (aluminum alloy), low water absorption | Partial metal replacement, PCB supports, automotive lightweight structures | Limited heat resistance; not recommended for continuous use above 120°C | |
| Nylon (Polyamide) | ~150°C | High tensile strength, fatigue resistance, good oil resistance | Gears, bearings, under-hood automotive components | Hygroscopic; moisture absorption affects mechanical properties and dimensions | |
| PC (Polycarbonate) | ~135°C | Excellent impact resistance, high transparency, good electrical insulation | Lighting lenses, electronic housings, safety covers | Sensitive to certain solvents (e.g., acetone) | |
| Commodity Plastics | PP (Polypropylene) | ~90°C | Extremely lightweight (about 1/8 the weight of carbon steel), acid/alkali resistant, cost-effective | Household water filters, light-duty electronic housings, food processing lines | Poor resistance to aromatic and chlorinated solvents |
| PVC (Polyvinyl Chloride) | ~60°C | Self-extinguishing, chemical resistant, cost-efficient | Construction fasteners, cable trays, low-temperature chemical fittings | Low heat resistance; UV exposure accelerates aging |
>> For detailed material properties, please see the Plastics Overview page.
Material Selection & Engineering Recommendations
1. Benefits of Reinforced Grades (+GF)
When base material strength is insufficient, reinforced grades can be selected:
- Glass Fiber Reinforcement (GF) significantly improves stiffness, creep resistance, and dimensional stability, while reducing thermal expansion.
- This ensures fasteners maintain clamping force without loosening under thermal cycling conditions (e.g., 200–250°C).
The laboratory of Link Upon Advanced Material Corp. provided the following data:
Sample: M6 × 20L socket cap screws
Source from Link Upon Advanced Materials Corp.
2. Considerations for Metal Replacement
- • Weight Reduction: Plastic screws (e.g., PP, RENY) weigh only 1/6 to 1/9 of steel fasteners.
• Functional Advantages: In semiconductor, medical, and electrical applications requiring non-magnetic, electrically insulating, corrosion-resistant, or metal-ion-free solutions, plastic fasteners are irreplaceable.
• Best Metal-Alternative Choice: RENY screws offer strength comparable to certain aluminum alloys, providing an optimal balance between plastic lightweight design and metal-like strength.
3. Procurement Cost Optimization Tips
Budget-Oriented Selection
- • For general structural fastening: PP / PP-GF or PVC
• For applications above 200°C without extreme chemical exposure: PPS is typically more cost-effective than PEEK
• For fluoropolymer fasteners: PVDF is generally more economical than PFA or PTFE
Performance-Oriented Selection
- • In highly corrosive environments (e.g., hydrofluoric acid, HF), PTFE or PFA, despite higher upfront costs, reduce downtime and maintenance expenses.
• PEEK offers excellent resistance to organic solvents, hydrocarbons, steam, and hot water while maintaining mechanical strength at elevated temperatures—an area where PTFE and PFA may be comparatively weaker.
>> 常用塑膠耐化學表，請參閱官網耐化表（等好了，再補放連結）。
4. Quick Environmental Compatibility Checklist
- • High purity / Semiconductor: PFA, PVDF
• Vacuum environments: PI (low outgassing)
• Outdoor & UV resistance: PVDF, PC (with coating), RENY
• Hydrolysis / Steam sterilization: PEEK, PE
5. Regulatory & Flame Retardancy Standards
UL94 Flame Rating Categories
| UL94 Rating | Representative Materials | Key Characteristics | Typical Applications |
|---|---|---|---|
| UL94 V-0 (Inherent) | PEEK, PPS, PEI, PFA | No additives required, low smoke, stable flame retardancy at high temperatures | Aerospace, semiconductor vacuum environments, high-voltage power modules |
| V-0 Equivalent / Modified | PVC, modified PA/PC/ABS | Self-extinguishing, customizable flame-retardant levels | Construction materials, cable conduits, electronic enclosures |
| UL94 HB (General) | RENY, PP, PE, ABS, PS | Low cost, easy processing | Consumer products, packaging, low-load structural components |
Standards Compliance:
Link Upon Advanced Materials Corp. supplies fasteners compliant with ISO / ANSI / JIS specifications.
>> For more information on plastic screw and nut specifications, or contact customer service.
Practical Selection Tip
Selecting plastic screws is like tailoring a custom suit. Engineers should first evaluate the maximum operating temperature, chemical exposure, and mechanical load of the application. When commodity plastics fall short under harsh conditions, upgrading to high-performance engineering plastics (such as PEEK or PPS+GF) may increase initial material costs—but it significantly extends equipment lifespan and reduces long-term maintenance frequency.
