Thermoforming engineers and material specifiers in aerospace, electronics, and specialty equipment fabrication continually seek polymer sheet materials balancing impact resistance, formability, and compliance with stringent flammability standards. Among the leading contenders in this space is Boltaron® 4335, a rigid, high-impact thermoplastic with proven performance under heat and mechanical stress. This material stands as a compelling alternative to KYDEX® T, particularly in applications where cost-efficiency, manufacturability, and regulatory compliance are paramount.
Material Composition and Performance
Boltaron® 4335 is a proprietary polyvinyl chloride (PVC) alloy engineered by SIMONA Boltaron. It offers high tensile strength (6,000 psi / 41 MPa), flexural strength (9,200 psi / 63 MPa), and an exceptional notched Izod impact resistance of 18 ft-lb/in (953 J/m) at room temperature. These properties allow it to absorb significant mechanical energy without failure, supporting use in structural components and protective housings.
The material exhibits a Rockwell hardness of 110 and a flexural modulus of 330,000 psi (2,275 MPa), maintaining rigidity under load while remaining sufficiently ductile for vacuum and pressure thermoforming. Importantly, Boltaron 4335 maintains excellent flame resistance, passing FAR 25.853 (a)(i) and (a)(ii) and earning UL 94 V-0, 5VA ratings down to a 0.045 mm gauge. Its radiant panel flame spread index is less than 10, supporting use in confined and ventilated environments such as aircraft interiors and electronic kiosks.
Thermoforming Characteristics
Forming Range: 335–370°F (168–188°C)
Mold Shrinkage: 0.5–0.7%
Pre-drying: Not required
These parameters make Boltaron® 4335 particularly attractive for rapid and repeatable production. The absence of a pre-drying requirement reduces cycle times and simplifies inventory management. Its consistent forming behavior and mold shrinkage performance facilitate tight dimensional tolerances in high-volume runs.
Comparative Analysis: Boltaron® 4335 vs. KYDEX® T
| Property | Boltaron® 4335 | KYDEX® T |
| Minimum Order Quantity (MOQ) | 500 lb | 600 lb |
| Lead Time | Shorter (varies by vendor) | Typically longer |
| Notched Izod Impact | 18 ft-lb/in | ~15 ft-lb/in |
| UL 94 Flame Rating | V-0, 5VA @ 3 mm | V-0, 5VA @ 3 mm |
| FAR 25.853 Compliance | Yes | Yes |
| Pre-drying Requirement | No | May be recommended |
| Forming Temperature | 335–370°F | 365–390°F |
| Flexural Modulus | 330,000 psi | ~320,000 psi |
| Applications | Aerospace interiors, kiosks, medical, pet carriers | Similar, often aerospace-dominant |
KYDEX® T, while widely recognized for its robustness and used extensively in aviation interiors, often incurs higher acquisition costs, longer procurement cycles, and a slightly higher forming temperature, demanding tighter thermal process control. For OEMs and fabricators requiring fast turnaround and cost efficiency without compromising mechanical or regulatory performance, Boltaron® 4335 delivers a strategic advantage.
Applications and Design Flexibility
Boltaron® 4335’s broad portfolio of available gauges (0.028″ to 0.250″) and customizable sheet sizes (up to 60″ x 120″) enhances its versatility. A virtually unlimited color range and texture options also support its deployment in visible or consumer-facing installations.
Typical applications include:
- Electronic and information kiosk housings
- Medical and laboratory equipment shells
- Aircraft-compatible portable containers
- Display systems for transportation terminals
- Ruggedized enclosures for sensitive instrumentation
Conclusion and Call to Action
For engineers and buyers prioritizing performance, flammability compliance, and cost control, Boltaron® 4335 offers a highly manufacturable, impact-resistant, and aesthetically adaptable thermoplastic alternative to KYDEX® T. Its shorter lead times, lower minimum orders, and thermoforming efficiencies support lean manufacturing and agile prototyping.
Ready to accelerate your thermoforming projects with Boltaron® 4335?
Contact RapidMade today for material consulting, sample requests, or a custom fabrication quote. Our advanced manufacturing solutions deliver speed, precision, and value—every time.
