POLYESTER RESINS
General Purpose Resin
It readily impregnates fibrous reinforcing materials such as glass, cloth or mat. It is suitable for the manufacture of general purpose mouldings such as machine guards, machine covers, furniture items, canopy etc. The resin is also used for potting and encapsulation, in decorative applications.
Typical Properties of the Liquid Resin
 Appearance  Clear, colourless to pale yellow
 Viscosity@ 25oC (cps)  750
 Specific gravity  1.12
 Acid value (mg KOH/gm)  31
 Volatile content (%)  36
General Purpose Resin ( Marine Application )
It readily impregnates fibrous reinforcing materials such as glass, cloth or mat. It is suitable for the manufacture of general purpose mouldings such as machine guards, machine covers, furniture items, canopy etc. The resin is also used for potting and encapsulation, in decorative applications.  
Typical properties of the liquid Resin
 Appearance  Clear, colourless to pale yellow liquid
 Viscosity @ 25° (cps)  700
 Specific gravity@25°C  1.30
 Acid value (mg KOH/g)  28
 Volatile content (%)  35
General Purpose Resin ( Fire Retardant )
It is recommended for applications in non-corrosive environment where flame retardancy is desired such as electrical appliance housings, modular housings, coolers, fans, vacuum cleaners, boat interiors and other general purpose mouldings. It is well suited for applica­tions by hand lay-up despite being more viscous, than general purpose resins. It demonstrates smoke suppressing properties and does not produce hazardous gases or vapours on burning.
Typical properties
 Appearance   A thick cream coloured opaque liquid of uniform  consistency
 Viscosity at 25°C  (cps)  (2000 +- 200 )
Bisphenol Resin
It has superior chemical resistance to a wide range of industrial effluents, acids, alkalies, salts and organic Solvents at elevated temperatures. This resign rapidly wets glass fibre in the form of cloth , mat or chopped fibre to produce laminates and mouldings.Bisphenol resign based glass reinforced plastic mouldings exhibit high flexural strength and retension of mechanical properties at elevated temperatures

It has superior chemical resistance to a wide range of industrial effluents, acids, alkalies, salts and organic Solvents at elevated temperatures. This resign rapidly wets glass fibre in the form of cloth , mat or chopped fibre to produce laminates and mouldings.Bisphenol resign based glass reinforced plastic mouldings exhibit high flexural strength and retention of mechanical properties at elevated temperatures

The outstanding chemical resistance of the laminates made from bisphenol resin to highly corrosive chemicals makes it ideal for combating corrosion problems and replacing scarce metals in wide range of applications in the chemical industries.
Typical properties
 Appearance   Pale amber cloudy liquid
 Viscosity at 25 0C(cps)   600
 Specific gravity at 25 0C   1.08
 Acid value (mg KOH/gm)   8
 Volatiles   50
Vinyl Ester Resign
It is a light yellow coloured low viscosity resin recommended for use in the manufacture of FRP composites via filament binding, hand lay-up, centrifugal casting bag moulding or pultrusion. It combines the excellent mechanical properties of epoxy resins with the ease of processing of the unsaturated polyester resins. It is notable for high temperature properties, extremely good chemical resistance, low shrinkage better adhesion and higher tensile elongation .
Typical properties
 Colour and appearance   Light yellow liquid
 Viscosity at 250C (cps)   400
 Styrene content (wt %)   42
 Acid value (mg KOH/gm)   8
 Specific gravity at 25 0C   1.06
Chemical Resistance
In general, Vinyl Ester Resin shows superior performance over bisphenol – fumeric acid polyester resigns for the following chemical:
  1. Chemicals which include hydrolysis, such as strong inorganic acids,
  2. Hydro Carbons
  3. Chlorinated compounds
Areas of Application
Vinyl Ester based composites have demonstrated economy and better price-to-performance characteristics than steel and its alloys as well as other conventional composites in many corrosive industrial environments because of excellent chemical resistance, low maintenance requirements, design flexibility and ease of installation.
It is used in the following areas of application
  1. chlor – alkali industries
  2. Paper-pulp industries
  3. Phosphoric acid and fertilizer productions
  4. Reinforced plastics for industrial floors
  5. Transportation and storage of corrosive chemicals
  6. Electrical insulation
Isophthalic Resin (Superior Grade)
It is a medium viscosity polyester resin based on isophthalic acid. It exhibits good mechanical and electrical properties together with a good chemical resistance compared to general purpose resins It rapidly wets the surface of glass fibre in the form of cloth, mat or chopped fibre to produce laminates and mouldings. Its superior chemical resistance towards most mineral chemical process equipment, storage tanks, tankers, ductings, hoods etc. for handling chemicals at ambient temperature.
Typical properties
 Appearance  A clear, pale yellow to yellow liquid
 Viscosity at 250C (cps)  650
 Specific gravity at 250C  1.11
 Acid value (mg KOH/gm)  16
 Volatile content (1%)  39
Isophthalic Resign (Fire Retardant)
It is a low flammability isophthalate polyester resins. This resin is suitable for glass reinforced plastic mouldings where the properties like water resistance, heat resistance and chemical resistance are desired along with fire retardant characteristics.
Typical Properties
 Appearance  A slightly thick, cream to white colored,opaque liquid.
 Viscosity at 250C(cps)  900
 Acid value (mg KOH/gm)  13.0
 Volatile content (1%)  33.0
Gelcoat Resin
This is a high molecular weight polyester resin based on isophthalic acid and neopentyle glycol it is offered as a gelcoat resin for use in conjunction with orthophthalate and isophthalate resins. It is particularly suited for mould making, cultured marble manufacturing and marine applications. The gelcoat provides exceptional resistance to water and bleaching agents. When used for decorative applications, it provides better colour stability, surface gloss, scratch resistance and weather durability
  Chemical Resistance
It has exceptional chemical and hydrolytic resistance. It gives an outstanding performance against 5% nitric acid, 25% sulphuric acid, 10% sodium hydroxide and water at 70 0C.
Roof Light Resign
It is a low viscosity, fast curing UV stabilized polyester resin designed for roof light sheet application. It has excellent light transmissivity and colour retention
Typical Properties
 Appearance  A clear light yellow liquid
 Viscosity at 25 0C (cps)  200
 Specific Gravity at 25 0C  1.11
 Refractive Index at 25 0C  1.528
 Acid value (mg KOH/gm)  26
 Volatile content (%)  40
Roof Light Resign (Uv Stabilized Isophthalic Grade)
It exhibits good chemical resistance and possesses superior mechanical and thermal properties. The resin has exceptionally good hydrolytic resistance making it an ideal choice for out door applications. It forms strong bond with fiberglass mat and depicts good wet-out characteristics. Because of good weathering properties and retention of glass and colour, it is also suited to numerous coating applications where corrosion protection is desired.
Typical Properties
Appearance : A clear colourless liquid
Acid value (mg KOH/gm) : 16.0
Specific Gravity at 25 0C : 1.16
Volatiles at 150 0C : 41
Refractive Index at 25 0C : 1.534
Curing Characteristics
Polyester Resins are cured by the use of free radical initiating catalysts mainly MEK Peroxide. Accelerators most commonly used are cobalt octoate and cobalt naphthanate.Catalysts and accelerator should be thoroughly evaluated before use
Caution
Accelerators should never be mixed with catalyst as this would cause explosion. Accelerator be blended into the resin first .Catalyst should be added immediately before use.
Storage
The resin should be stored at a temperature not exceeding 30 0C at 15-25 0C in securely closed containers. At higher storage temperatures the storage life decreases sharply. Presence of moisture also affects the storage life of the resin and leads to turbidity in the resin. The resin should also not be exposed to direct sunlight as this would lead to premature gelation