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SpEC Polysulphide joint sealant

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A two part, low modulus, chemically curing gun grade polysulphide joint sealant developed specifically for dynamic joints

It has two types of application, Gun grade application or pouring grade application.

SpECseal 625HD is a two part, low modulus,
chemically curing gun grade polysulphide joint
sealant developed specifically for dynamic joints. It is
based on a liquid polysulphide polymer which when
mixed with the hardener, cures to form a tough rubber like seal.

For sealing and resealing high movement joints
in building and civil engineering structures and for
sealing joints in structures which are subject to high
rapid movements.

• Tough and resilient seal
• Provides permanent and uniform water tight seal
• Excellent adhesion to most surfaces
• Stays flexible – no brittle or cracking due to UV
• Gun grade for vertical and overhead applications
• Good chemical & weathering resistance
• Non-toxic once cured
• High resistance to ageing


Typical Properties @ 20±3 °C
Movement accommodation
factor (ASTM C 719)
Pot life
Full cure time
Hardness (Shore ‘A’)
Appearance after
Pull-off strength
Tensile strength
Elongation @ break
Volume shrinkage
Effect of heat ageing
Solids content

SpECseal Primer 25 for use on porous and nonporous surfaces.

SpECseal Primer 25 is a two component primer.
The base and hardener components should be
mixed together for 2 minutes to produce a uniform
The primer should be applied to clean, dry surfaces
prior to the installation of backer rod or bond
breaker tape.
The freshly mixed SpECseal 625HD should be
applied after the primer is just touch dry. The
sealant should be applied between 30 – 180
minutes after priming.
If the primer is left to dry longer than 3 hours
the surfaces must be re-primed prior to applying
the sealant.
SpECcord or SpECcell Polyethylene should be
used to control the depth of the joint to the
recommended thickness. Where joint design or
depth of joint will not permit the use of backing
rod, use a bond breaker tape over the cut back
joint filler.
SpECseal 625HD is the gun grade and is supplied
in 2.5 litre composite packs with the base and
curing agent placed in the tin ready for mixing.

SpECseal Primer 25 is supplied in one litre 2 part
Length of joint in metres filled/1 litre of SpECseal

SpECseal Primer 25
SpECseal Cleaning Fluid
SpECseal paddle mixer
SpECseal 600ml solid barrel gun
SpECcord closed cell polyethylene back-up cord
To maintain the shelf life of 12 months, SpECseal
625HD should be stored in the original sealed
containers at temperatures between 5°C and 25°C.

Soon after mixing, the SpECseal 625HD should
be loaded into a SpEC 600 ml solid barrel gun
using a steel follower plate.

The joint faces should be protected with masking
tape to facilitate tooling.
SpECseal 625HD should be gun applied firmly
into the joint such that it makes positive contact
with the joint faces.
The sealant should then be tooled off to compact
it against the joint sides and the masking tape
removed immediately after tooling.

Clean equipment with SpECseal Cleaning Fluid
immediately after the tooling is finished.
Minimum +5°C
Maximum +60°C
SpECseal 625HD is supplied in 2.5 litre tins

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