Sealents- Uni Seal P

Uni Seal P is a two component polysulphide sealant which, when mixed together, cures to form a flexible rubber seal. It gives excellent adhesion to glass, metals, concrete, masonry, wood, plastics, and many other building substrates. It is capable of withstanding repeated extension and compression without loss of adhesion. Uni Seal P gives outstanding resistance to deterioration by weathering, oils, fuel, water, ultra violet, ozone etc, remains unaffected by most alkalis, and dilute acids.

Concrete Admixture


Universal Construction Chemicals


Concrete Admixture


Universal Construction Chemicals


Concrete Admixture


Universal Construction Chemicals


Uni Seal P Uses

Two Component Pourable Grade Polysulphide Joint Sealant

Sealing of expansion, contraction & construction joints in building structures such as :

  • Basements and subways
  • Retaining walls & floors
  • External walls and claddings of high-rise buildings
  • Roof terraces & ceilings especially structural expansion joint running through the ceiling.
  • Sealing of dynamic structural cracks.
Sealents- Uni Seal P

Uni Seal P Advantages

  • Excellent chemical resistance.
  • Excellent UV resistance.
  • High movement accommodation.
  • Resists Jet fuels and Aviation fuels.
  • Cure at ambient temperature to a tough, elastic &
  • Flexible rubber like material.
  • Bonds strongly to most of the building materials.
  • Durable, remains unaffected by UV rays, Ozoneand weathering conditions.
  • Resistant to water, salt water, 10% diluted, acids except nitric acid, 10% alkalies, most of the

Typical Properties & Specifications

Sr. No. Properties Specification
1 Form Twp-part compound Base :
Paste, Hardener : Paste
2 Colour Grey (mixed)
3 Specific Gravity 1.50 – 1.55 kg/lit.
4 Staining Nil
5 UV Resistance Good
6 Chemical Resistance Excellent
7 Movement Accommodation 30 % in Butt joints, 50 % in Lap joints
8 Pot Life Min. 2 hrs at 30 C
9 Setting Time 18 hrs. at 30 C
10 Cure Time 7 days at 30 C
11 Flash Point Over 65 C

Instruction for Uni Seal P Use

Two Component Pourable Grade Polysulphide Joint Sealant

Surface Preparation

  • Surface preparation is the most important step before application of sealant to get best results and to avoid failure.
  • The joint surface must be dry, free from dust, coatings, bituminous mastics, concrete curing agents, mould release agents, oils, greases and loose particles.
  • Clean the joint surface by wire brush and sanding with emery paper.
  • Remove dust by compressed air or paint brush.
  • Wipe out oil & grease with a cleaner.

Back Up Material

Insert compressible polyethylene, polyurethane, thermocol foam, neoprene, polyethylene, butyl rods as a back-up material to control depth of sealant in the joint & to provide support for tooling of the sealant.


Apply two coats of Uni seal by brush on the sides of the joint surface at an interval of 30 minutes.

Masking Tape

Apply masking tape such as self-adhesive polyethylene, cellophane or cloth tape on both edges of the joint. It is used to improve the neatness of the finished seal by protecting the face edges of the joint. It may be removed immediately after tooling of the sealant.


The Base and Hardener compounds supplied are packed in pre- weighed quantity as per the mixing ratio. After the application of Primer, mix the material of individual container. Transfer entire quantity of Hardener to the Base compound tin and mix it thoroughly to a uniform, homogenous grey colour. Mixing can be done manually with spatula/palette knife or special flat stirrer attached to a low speed electric mixer less than 500 r.p.m.


Apply the mixed gun grade compound by means of a spatula or by filling into a plastic cartridge which is then placed into the hand held caulking gun into the joint. Avoid application below 10°C temperature.

Tooling and Finishing

It is desirable that a smooth surfaces is obtained. Tool the sealant by pressing the puffy knife or flat tool against the sealant surface, moving along the length of the joint. Tooling breaks air bubbles and exposes any air pockets present. Tooling compresses the sealant, thus promoting adhesion to the joint sides.
After tooling, the masking tape should be removed immediately. Soap solution can be used to smoothen the sealant surface.

Tools Cleaning

Tools and equipment can be easily cleaned with a UNI TOOL CLEANER.

Estimating Of Quantity

To estimate quantities of sealant required, the formula given below can be used to calculate the number of (1 Kg or 5 Kg) tins needed. To calculate the weight (in Kg.) of sealant required for a joint of particular length (in meters), the following formula can be used : Weight in Kg = (1.6 X W X D X L)/1000 Where W & D are in mm and L is in metre, Example : (1) W (Width of joint) = 10 mm (2) D (Debth of joint) = 10 mm (3) L (Length of joint) = 12.5 mtr; Weight in Kg = (1.6 X 10 X 10 X 12.5) / 1000 = 2.00 Kg of sealant, Estimates for Uni Seal P Primer are arrived at as below : 1 Litre of Uni Seal P Primer would cover 6 to 7 m² of joint area or about 1 litre of Uni Seal PRIMER would be required for 30 Kg of Uni Seal P sealant.


Uni Seal P is supplied in 1 kg. 5 kg. containers

Shelf Life & Storage

Uni Seal P has a shelf life of 12 months from date of manufacture when kept at a temperature between 5 C to 45 C and store in the original, unopened bags. All material shall be stored under cover in a manner that will prevent damage preferable on pallets and protected from excessive heat and moisture. Do not freeze.

Quality Assurance

Universal Construction Chemicals is a firm of Assessed Capability. The company's quality system conforms to ISO 9001:2015.

Health & Safety

Uni Seal P should not come into contact with skin, eyes or be swallowed. Protective glasses should be worn during mixing and application. Should Uni Seal P come into contact with skin, remove before hardening by washing with soap and water. Should accidental eye contact occur wash with plenty of water and seek medical advice. If swallowed seek medical advice immediately. Do not induce vomiting. For full health and safety data refer to Product Safety Data Sheet.

Uni Seal P Standards Compliance

  • British Standard : BS:4254 : 1983
  • Indian Standard : IS 12118 (PT 1 & 2) – 1987 ASTM C-920-87, Type M, grade NS, Class 25.