Transparent, low-halogen and anti-yellowing epoxy pouring sealant and preparation method thereof

Abstract

The invention discloses a transparent, low-halogen and anti-yellowing epoxy pouring sealant applied to the micro-electronics field and the LED field and a preparation method of the transparent, low-halogen and anti-yellowing epoxy pouring sealant. The pouring sealant comprises a component A and a component B, wherein the component A comprises the following raw materials in parts by weight: 60-100 parts of low-halogen bisphenol A epoxy resin, 0.1-2 parts of an organic silicon defoamer, and 0.05-1 part of toner; the component B comprises the following raw materials in parts by weight: 60-100 parts of methylhexahydrophthalic anhydride, 0-3 parts of flexibilizer, 0.2-1 part of a light stabilizer, and 1-5 parts of a curing accelerator; the mass ratio of the component A to the component B is (1-1.2):1. The preparation method is characterized in that the component A is dispersed for 20-50min at high speed according to the formula; the component B is mixed according to the formula; then the temperature is increased to be 60-80 DEG C; the mixture is stirred for 1-3 hours. According to the transparent, low-halogen and anti-yellowing epoxy pouring sealant, a halogen-free intermediate-temperature curing accelerator is used; the mixing ratio of the materials and the production process are optimized to produce the transparent, low-halogen and anti-yellowing epoxy pouring sealant which meets the requirement of EU on the content of halogen in pouring sealing materials; meanwhile, the transparent, low-halogen and anti-yellowing epoxy pouring sealant is outstanding in anti-yellowing performance and outstanding in toughness.

Description

technical field [0001] The invention relates to the technical field of potting glue, in particular to a transparent, low-halogen, anti-yellowing epoxy potting glue and a preparation method thereof. Background technique [0002] According to the curing temperature, epoxy potting glue can be divided into high temperature curing (curing temperature ≧ 150 ℃), medium temperature curing (curing temperature 80~120 ℃), room temperature curing (curing temperature 15~40 ℃) and low temperature curing (curing temperature ≦ 15°C) four categories. High-temperature curing has high requirements on the quality of parts. When the curing temperature is ≧150°C, some parts will soften and deform, which will affect the performance of the overall cured product. The curing reaction time of room temperature and low temperature curing is long (curing time≧24H), and the cured product is brittle, with poor mechanical properties and temperature resistance. Medium temperature curing epoxy adhesive can ...

AI Technical Summary

Problems solved by technology

As a curing agent for epoxy resin, acid anhydride has excellent mechanical properties, high temperature thermal stability and dielectric properties. However, due to the low curing activity of acid anhydride, the curing process of epoxy / anhydride system requires higher temperature and longer time. Therefore, a certain amount of curing accelerator needs to be added when the epoxy / anhydride system is cured

[0004] At present, most of the medium-temperature curing accelerators contain halogens, which have pollution problems and cannot meet the requirements of the European REACH regulations; the existing halogen-free medium-temperature curing accelerators have the problem of yellowing of the cured epoxy resin during the curing process, which cannot meet the requirements of the LED display. , lighting and other fields that require high transparency