BYK-S 740 is a styrene emission suppressant for unsaturated polyester resins. It reduces monostyrene emissions in orthophthalic resins by up to 90% without affecting the interlaminar adhesion of polyester resin laminates.

Functions: Styrene Emission Suppressant

Compatible Polymers & Resins: Unsaturated Polyester (UPE)

Enhanced TDS

Identification & Functionality

Manufactured By
Composite Materials Functions
Technologies
Product Families

Applications & Uses

Application Area
Compatible Polymers & Resins
Use Level
0.5 - 1% (Additive Ambient Curing Resin Systems), 0.2 - 0.5% (Non - Thixotropic)
Application Information

Ambient curing resin systems


Special Features and Benefits
BYK-S 740 is a highly effective additive for reducing monostyrene emission in orthophthalic resins for open mold processing techniques. Using the product does not adversely affect interlaminar adhesion.
Recommended Use
BYK-S 740 is particularly recommended for orthophthalic resins and can also be used in isophthalic resins.
Recommended Levels
0.5-1% additive (as supplied) based on the total formulation.
The above recommended levels can be used for orientation. Optimal levels are determined through a series of laboratory tests.

Incorporation and Processing Instructions
BYK-S 740 should be added to the resin whilst stirring before adding other formulation components. If you require even easier handling, we recommend melting the product (max. 40 °C) and stirring the liquid BYK-S 740 into the resin. If melting is not possible, incorporating 5-20 % monostyrene creates a soft paste, which readily dissolves in the resin. The mixture of BYK-S 740 and monostyrene should not be stored any longer than 24 hours and should be mixed well before processing.
Special Note
In non-thixotropic resins, BYK-S 740 tends to flocculate and floats to the resin surface during storage. In the case of separation, the resin must be stirred before processing. To achieve good storage stability of BYK-S 740 in non-thixotropic resins, 0.2-0.5 % BYK-LP W 6236 can be used in combination with BYK-S 740.

Properties

Physical Form
Typical Properties
ValueUnitsTest Method / Conditions
Density (at 40°C)0.86g/ml-
Refractive Index (at 40°C)1.456--
Flash Point66.0°C-
Acid Valuemax. 7mg KOH/g-
SDS Physical and Chemical Properties
ValueUnitsTest Method / Conditions
Lower Explosion Limit0.6%V
Upper Explosion Limit6%V
Auto Ignition Tempertauremin. 200°CDerived, DIN 51794
Flash Point66°CDIN 51755, Abel-Pensky
Initial Boiling Point176°CDerived
Melting Point (May crystallize, even at room temperature.)max. 0°CDerived
Density (at 40°C)0.86g/cm³Oscillating U-tube
Vapour Pressure (at 20°C)3hPaDerived
Kinematic Viscosity (at 40°C)40mm²/s-
AppearancePaste--
ColorLight yellow--
Flammability (liquids)Sustains Combustion--
Immiscible InWater--
pH (at 20°C, Concentration: 1%)6-Universal pH-Value Indicator
Composition Data

Solution of hydroxypolyesters with paraffin wax.

Regulatory & Compliance

OEM Specifications

Storage & Handling

Storage Conditions

Separation or turbidity may occur during storage and transportation. Mix well before use.