LORD Thermoset SC-309 thermally conductive silicone encapsulant is a two-component system that can meet the requirements of high thermal conductivity in the field of electrical / electronic packaging, while maintaining the ideal characteristics of silicone and can be cured at room temperature. It can also be cured at high temperature to maximize adhesion.

Description

LORD Thermoset SC-309 thermally conductive silicone encapsulant is a two-component system designed to provide excellent thermal conductivity for electrical/electronic encapsulating applications, while retaining desirable properties associated with silicones. Thermoset SC-309 encapsulant can be either room temperature cured or heat cured for maximum adhesion.

Features and Benefits

Low Stress – exhibits low shrinkage and stress on components as it cures.

Durable – composed of an addition-curing polydimethyl siloxane polymer that will not depolymerize when heated in confi ned spaces.

Low Viscosity – maintains low viscosity for ease of component encapsulation compared to other highly thermal conductive materials.

Environmentally Resistant – provides excellent thermal shock resistance.

UL Rated – provides excellent fl ame retardancy; UL 94 V-O certifi ed.

Application

Mixing – Thoroughly stir each component prior to mixing together. Mix Thermoset SC-309 resin with Thermoset SC-309 hardener at a 1:1 ratio, by weight or volume. Automatic meter/mix/dispense equipment may be used for high volume production.

Unless a closed-chamber mechanical mixer is used, air will be introduced into the encapsulant system either during mixing or when catalyzing the mixture. Electrical properties of the silicone encapsulant are best when air bubbles and voids are minimized. Therefore, in extremely high voltage or other critical applications, vacuuming may be appropriate.

Applying – Apply silicone encapsulant using automatic meter/mix/dispense equipment.

Avoid applying Thermoset SC-309 encapsulant to surfaces that contain cure inhibiting ingredients, such as amines, sulfur or tin salts. If bonding surface is in question, apply a test patch of Thermoset SC-309 encapsulant to the surface and allow it to set for the normal cure time.

Typical Properties*

Typical Cured Properties**

Curing – Allow encapsulant to cure for 24 hours at room temperature (25°C), for 15 minutes at 100°C, or for 10 minutes at 120°C. This time-at-temperature profi le refers to the time the material should be allowed to cure once it reaches the target temperature. Allowance should be made for oven ramp rates, parts with large thermal mass and other circumstances that may delay material actually reaching the target temperature.

Shelf Life/Storage

Shelf life of each component is six months from date of manufacture when stored at 25°C in original, unopened container. The material must be periodically rotated within its container to maintain maximum shelf life. Settling will occur if not mixed.

Thermoset SC-309 encapsulant evolves minute quantities of hydrogen gas. Do not repackage or store material in unvented containers. Adequately ventilate work area to prevent the accumulation of gas.

Cautionary Information

Before using this or any LORD product, refer to the Material Safety Data Sheet (MSDS) and label for safe use and handling instructions.

For industrial/commercial use only. Must be applied by trained personnel only. Not to be used in household applications. Not for consumer use.