How can I change the performance of the silicone encapsulant base agent?

There are two ways to change the performance of the silicone encapsulant base agent, the curing time and the operation time of most polyurethane encapsulants is 1-45 minutes. In some cases, the maximum operating time may vary. But don't try to change the operating time with the reinforcing agent, the operating time can be adjusted by Weifu; For manual operation, the handling time is approximately 45 minutes and the curing time is approximately 4-24 hours, depending on the type of base agent in the product, temperature and dosage.

Viscosity: Do not alter viscosity by adding more or less reinforcing agents. The viscosity can be changed by:

1) A low-viscosity curing agent will reduce the viscosity of the mixture, but this will also change the mechanical and thermal properties of the cured polyurethane. (2) Weifu can increase the viscosity by adding thixotropic agent, which also helps to improve the stability and thixotropy of the liquid main agent and curing agent mixture without changing its mechanical and thermal properties.

Hardness: Do not attempt to change the hardness by adding too much base or hardener, as this will negatively affect the mechanical properties of the cured polyurethane. Its hardness can be slightly changed by using another type of hardener.

If you need a different level of hardness, use a different base agent.

For addition molding or condensation silicone encapsulants, the performance of the main agent can only be achieved by changing the formula of the original material.

Dow silicone potting glue AB glue!

I will introduce the condensation silicone potting glue from two aspects, the glue mixing process and the precautions for operation!

1. Mixing process

Before use, the main agent and curing agent are fully stirred evenly, and the glue is prepared according to the specified proportion.

Stir at 1500-2000 rpm for 2-5 minutes. The agitator should be placed slightly lower in the center of the liquid level, and the depth of the stirrer inserted into the glue is 1 2-2 3 (subject to the height of the liquid level).

After stirring well, vacuum degassing of the rubber (if required) so that the air bubbles are completely removed, and the potting can be carried out.

The A and B components that have been opened need to be resealed, otherwise the curing performance will be affected.

When stirring, it should go up and down several times to make the material as uniform as possible.

(2) Precautions

Before use, check whether the packaging of agent B is damaged, and replace it if it is damaged to avoid use.

The main agent should be stirred well before use.

Before the glue is cured, it should not be exposed to rain, solvents, etc., and avoid direct sunlight as much as possible.

If a matte finish is required, the module must be placed in a well-ventilated environment.

Before dispensing the same container, the residue inside the container must be cleaned and the unused material must be resealed.

When a material needs to be adhered to in front of the cavity (e.g., PC, PCB, etc.), it must be used after prior application experiments, and depending on the situation, it may be necessary to clean the material.

In most cases, silicone rubber can be used normally between minus 40 and 200 degrees Celsius, but at higher or lower temperatures, in addition to higher requirements for adhesion or sealing materials, the curing properties of the glue itself also change, and it needs to be fully tested before it can be used.

1. Closed fitting excitation: First of all, a shrinking car socks type low-density silicone potting adhesive needs to accurately weigh A and B components (curing agent) according to the ratio of A and B components.

2. Secondly, it should be noted that the glue of component A should be properly stirred in weighing, so that the filler that sinks to the bottom is dispersed into the glue.

3. In the final preparation, the A component and B component are prepared according to the requirements of the formula, and cooled to room temperature.

Silicone encapsulant: Silicone encapsulant refers to a class of electronic encapsulant made of silicone rubber, including one-component silicone encapsulant and two-component silicone encapsulant. Silicone encapsulants are generally soft and elastic.

There are many types of silicone potting compounds, and different types of silicone potting compounds have great differences in temperature resistance, waterproof performance, insulation performance, optical properties, adhesion to different materials, and softness and hardness.

Ingredients--mixing--vacuuming--potting--standing (or heating) at room temperature--checking and warehousing. Two-component potting equipment can be used, simplifying the entire operation process while also saving operating time and reducing raw material waste.

The two-component silicone encapsulant can be made with optical level transparency. It can be made into self-adhesive components for easy repair.

One-component silicone potting adhesives generally require high temperature curing, some varieties require a little curing at 80 degrees, and some require more than 150 degrees to cure. In general, the lower the curing temperature requirement, the shorter the shelf life at room temperature, and vice versa, so many one-component silicone encapsulants even require cryogenic freezer storage.

Causes of problems: Poisoning or expiration of catalysts in addition gels; Incomplete curing due to insufficient curing temperature or insufficient time.

The cause of the problem may be: due to the error of the measuring instrument or human factors caused by the wrong glue ratio; The product exceeds the storage period or is close to the storage period, resulting in failure and reduced efficiency; Improper storage causes the catalyst in the product to fail or reduce the efficiency; There are factors that poison the catalyst in the environment when used, such as organic compounds containing phosphorus, sulfur and nitrogen, or polyurethane, epoxy resin, unsaturated polyester, condensed room-temperature vulcanized silicone rubber and other products are used at the same time as addition silica gel; Incomplete curing due to insufficient curing temperature or insufficient time.

Solution: Measuring instruments must be calibrated regularly; The two-person system is adopted when dispensing glue in two groups; Ensure the storage conditions required by the manufacturer, pay attention to the storage period, and follow the "first-in, first-out" principle when using to ensure that it is used in the shortest possible effective period. Keep away from other potentially harmful organic compounds in the workplace, and strictly prohibit the use of rubber compounds immediately after smoking.

Zhaoshun Technology's silicone potting adhesive is good.

The silicone thermally conductive potting adhesive of Hongye silicone is used for deep potting of power modules and electronic components, especially for HID power modules. and other metal, plastic, glass and other bonding seals with flame retardant requirements.

The parameters before and after curing are as follows:

The models are not the same, and they are not the same.

The condensed potting silicone of red leaf silicone is a two-component, condensed type of room-temperature curing liquid silica gel. The appearance is black, it has ultra-high hardness after curing, has flame retardant and thermal conductivity, mechanical potting, and fast curing speed at room temperature.

The performance parameters are as follows:

Before curing and after curing.