Sazilast 503 — thixotropic polysulfide sealant of the 500 series
Thixotropic sealant for vertical and inclined joints of bridges and tunnels under mechanical load; tensile strength at break from 1.5 MPa.

Sazilast 25 is a facade sealant: a two-component non-shrinking polyurethane compound for moving panel joints and cracks in above-ground parts of buildings. It withstands joint movement of ±25%, elongation at break is at least 350%, service is from −60 to +70 °C, and the predicted service life is 15 conventional years. It can be applied to a damp but not wet substrate at temperatures from −15 to +40 °C, and the cured joint can be painted with water-based acrylic paints. It is supplied in a 10.5 kg kit.
| Manufacturer | Sazilast (SAZI) — OOO PK “SAZI”, Ramenskoye |
|---|---|
| Type | joint sealants |
| Use | joints and junctions |
| Base | two-component non-shrinking polyurethane sealant (A — polyol, V — polyurethane prepolymer) |
| Colour | white, grey |
| Packaging | 10.5 kg kit |
| Application method | mix components A and V with a low-speed drill at 300–350 rpm for at least 10 min; in cold weather condition to +15…+25 °C before mixing; do not add solvents or water; substrate damp but not wet, cleaned; a compressed polyethylene foam backer rod is placed in the joint (no three-sided adhesion); apply by spatula; working layer from 3 mm to 1/2 of the joint width |
| Application temperature | from −15 to +40 °C |
| Curing | pot life at least 6 h at 23 °C; full cure 7 days at 23 °C |
| Key properties | permissible movement amplitude ±25%; nominal tensile strength at break at least 0.25 MPa; elongation at break at least 350% (on joint specimens); cohesive failure; Shore A hardness after 24 h 20–30; flow not more than 2 mm; density 1.6 g/cm³; service from −60 to +70 °C; predicted service life 15 conventional years (3 mm layer, movement ±25%); can be painted with water-based acrylic paints |
| Layer thickness | working layer at least 3 mm, not more than 1/2 of the joint width |
| Consumption | 96 g/linear m (20 mm joint, 3 mm layer) |
| Shelf life | 6 months at −20…+30 °C in undamaged packaging, protected from moisture, dust and direct sunlight |
| Standards | STO 038-37547621-2016 (with amendment No. 1 of 25.05.2023); GOST R 59522-2021, classes 1 and 2P; certificate of conformity (manufacturer OOO PK “SAZI”, production — Ramenskoye) |
Data from the manufacturer’s technical data sheet. The coating system, number of coats and quantity are selected for your project on request.
Thixotropic sealant for vertical and inclined joints of bridges and tunnels under mechanical load; tensile strength at break from 1.5 MPa.
Two-component facade sealant for panel joints and cracks in above-ground parts of buildings; classic formulation, applied from −15 to +40 °C.
Free-flowing polysulfide sealant for pouring into horizontal and hard-to-reach joints of roofs, roads, bridges and tunnels; elongation at least 200%.
Winter version of the facade sealant for panel joints and cracks: applied at temperatures from −20 to +25 °C, brush application permitted.
Polyurethane facade sealant for wide panel joints: increased sag resistance, applied at temperatures from −15 to +45 °C.
Low-modulus pourable sealant for joints of bridges, tunnels and water conduits without direct mechanical load; elongation at break from 350%.