When using the potting compound, sometimes it will not cure, and this phenomenon is called the poisoning of the potting compound. What are the reasons for the poisoning and non-curing of silicone potting glue? Today, I will talk about the reasons and solutions for this phenomenon.
Analysis of the Causes of Poisoning and Non-curing of Silicone Potting Adhesive
1. It may be due to the error of measuring instruments or human factors that cause the wrong proportion of glue.
2. The product has exceeded the storage period or is close to the storage period, resulting in failure and reduced performance, or the catalyst in the product has failed or has reduced performance due to improper storage during storage.
3. The environment during use contains organic compounds such as phosphorus, sulfur, nitrogen, and ionic compounds containing alkyne and polyvinyl compounds or Sn, Pb, Hg, As and other elements, and the two-component addition type silicone potting contact A certain amount of the above compounds will inhibit the curing reaction of the adhesive, so that the colloid is not cured or cured insufficiently.
4. Use polyurethane, epoxy resin, unsaturated polyester, condensed room temperature vulcanized silicone rubber and other products together with the addition of silica gel.
5. The curing temperature is not enough or the time is not enough to cause incomplete curing.
6. Internal direct contact, if the circuit board contains uncleaned rosin flux, etc., or the plasticizer used in the insulating plastic that the potting compound contacts contains toxic substances, it will not cure or cure incompletely at the contact part .
What are the solutions to potting glue poisoning and non-curing
1. Completely and accurately distribute the ratio.
2. The container must be clean, preferably a glass container.
3. Stir well.
4. Use according to the storage period, and the expired potting glue is not used.
5. Pay attention to temperature and humidity, heat and cure if necessary.
6. When using addition-type potting glue, avoid contact with organic compounds containing phosphorus, sulfur, and nitrogen, or use polyurethane, epoxy resin, unsaturated polyester, condensation-type room temperature vulcanized silicone rubber and other products together with addition-type silicone rubber. Prevent poisoning from curing.
In order to solve the last problem above, the general silicone potting compound will add anti-poisoning agent to the colloid, and the silicone potting compound with anti-poisoning agent will no longer be affected by sulfur, phosphorus, nitrogen, tin and other substances.
