This 5-cavity silicone mold is designed for casting dumbbell-shaped tensile test specimens from soft biomaterials including PDMS, polyacrylamide hydrogels, PVA hydrogels, fibrin, alginate, gelatin, collagen composites, and silicone elastomers. The dumbbell geometry forces fracture to occur in the narrow gauge section — delivering reliable, repeatable mechanical characterization data that rectangular strip specimens cannot provide.
 
Specimen geometry:
Total length: 75 mm | Gauge length: 25 mm | Gauge width: 4 mm | Shoulder width: 13 mm | Thickness: 2 mm
This geometry is optimised for the force ranges (0.1–20 N) typical of laboratory tensile testers used in soft biomaterials research (e.g., Instron 5943, TA Instruments RSA-G2, Zwick/Roell Z0.5). The 2 mm specimen thickness is compatible with standard soft tissue grips and pneumatic clamps.
 
Suitable materials: PDMS (Sylgard 184, Ecoflex, Dragon Skin) with usage of proper release agents · Polyacrylamide (PAAm) hydrogels · PVA hydrogels · Agarose and gelatin gels · Alginate hydrogels · Fibrin gels · Collagen and collagen-composite scaffolds · Cellulose nanofiber biocomposites · TPU films · Soft silicone membranes (with proper release agent)
 
Related standards and comparable geometries: ASTM D412 Die C (rubber and elastomer tensile — wider and thicker, same dumbbell concept) · ISO 37 Type 2 (rubber tensile — similar geometry) · ISO 37 Type 4 (micro-dumbbell) · JIS K6251 (Japanese rubber standard) · ISO 527-3 (thin film/sheet tensile)
Used in: soft tissue biomechanics · hydrogel material characterization · scaffold mechanical testing · wearable device material qualification · PDMS device fabrication · drug delivery matrix testing · bioreactor substrate testing
5-cavity design allows one mold pour to produce a complete specimen set (n=5) for statistically valid results — no second pour required.
Mold material: platinum-cure silicone (tin-free, biocompatible, autoclave-safe).
 
Made in Ontario, Canada.
 
Need a different gauge geometry, thickness, or cavity count? We produce custom soft-matter molds for academic and industrial research labs — ISO 37 Type 1/2, D412-C, and fully custom profiles available on request.
We also supply microfluidic channel molds, tissue microarray (TMA) molds, and other PDMS casting tools.