Incure Uni-Weld™ Plastic Bonder — Matching Grade to Substrate and Mechanical Demand
Plastics don't behave like metal or glass at a bond line — dissimilar coefficients of thermal expansion, lower surface energy, and a much wider range of flexibility mean a single "plastic adhesive" rarely fits every joint. A wicking grade that penetrates a pre-assembled housing by capillary action and a structural grade dispensed before assembly solve genuinely different problems, which is why Incure's Uni-Weld™ plastic bonder line spans both ends rather than offering one formulation for every job. Nine Grades, Wicking to Structural Viscosity across the line runs from 100 cP up to 84,000 cP, and that range maps directly to how the adhesive gets applied. Ultra-low viscosity grades — 3271 at 100–200 cP, 1462 at 250–500 cP, 1453 at 350–700 cP — penetrate already-assembled joints by capillary action, suited to parts that are mated first and bonded second. Mid-range grades like 1417 (5,700–11,400 cP) and 1444 (1,900–3,800 cP) dispense before assembly for gap-filling and structural work. The highest-viscosity grade in the catalog runs 42,000–84,000 cP, formulated for load-bearing structural bonds and potting rather than wicking into a fine gap at all — that same grade also carries the widest service temperature range in the line, rated from −55°C to 150°C against −55°C to 80°C on most of the wicking grades, reflecting its role in higher-demand structural joints rather than delicate capillary-fill work. Picking a grade starts with which of those two application methods the joint actually calls for, not with viscosity as an abstract preference. Elongation Spans Nearly 300x Across the Line The mechanical range is just as wide as the viscosity range, and the two don't move together. 1072, a wicking grade suited to rigid bonding, cures to just 13% elongation and Shore D76–D86 hardness — stiff, dimensionally stable, not built to flex. At the other end, 1483 reaches roughly 3,800% elongation at Shore D50–D60, formulated for joints that need to absorb vibration and thermal expansion rather than resist deformation. 1417 (346% elongation) and 1444 (355% elongation) sit in between, tough enough for structural loads while still damping vibration on solder joints and wire tacking. Selecting a grade for a specific mechanical property means checking its elongation figure directly rather than assuming "structural" and "flexible" describe the same thing — they're opposite ends of this line, not synonyms. Tensile Figures Are Substrate-Limited, Not Adhesive-Limited Grades in this line are rated up to 10,800 PSI tensile strength — but that figure, marked with a fracture indicator in Incure's spec table, reflects the polycarbonate test substrate failing before the adhesive bond does, not the adhesive's own strength ceiling. That distinction matters when specifying a grade for a genuinely high-load joint: the 10,800 PSI number describes what a PC substrate can take before it breaks, which may be a different limiting factor than what the adhesive itself is capable of on a tougher substrate. Every grade in the catalog is tested and reported the same way, so the substrate-fracture caveat applies across the line rather than to one outlier figure — worth…