Polymers flame retardant can be divided into halogen and halogen-free
two categories. The serious disadvantages of halogen flame retardant is
that it reduces UV stability of flame retardant polymer substrate. It
burns to produce more smoke, toxic gases, corrosive gases, and halogen
flame retardants generally use with antimony trioxide together,
therefore, smoke and toxic gases generate more.
In the research
and application of fire retardant materials, people have gradually
realized that smoke suppression and flame retardancy of equal
importance. But for some materials, smoke suppression even more
important than flame retardant, such as widely used materials PVC.
There
are variety of halogen-free flame retardant. According to the types of
flame retardant elements, they are often divided into
magnesium-aluminum, phosphorus, nitrogen, phosphorus-nitrogen, Silicon,
antimony, boron, molybdenum and graphite etc. Currently, consumption of
halogen-free flame retardant in industry mainly are phosphorus
(phosphonic) acid (includes halogen-containing derivative), zinc Borate,
hydroxide, magnesium hydroxide, red phosphorus and antimony trioxide.
Flame retardants are one of the most important polymer processing
additives.
DOPO derivatives of its phenolic hydroxy or amino
derivatives can be used as curing agent for polymers. They cured epoxy
resin are very different from brominated epoxy resins, especially in
flame retardant, thermal stability. Today's research and development of
organic phosphorus compounds have a rapid development from chain-like
structure to the ring. Such as phosphine phenanthrene compounds - DOPO
and its derivatives has been paid attention due to its unique molecular
structure (benzene and phenanthrene ring structure) and and have shown a
great deal of excellent performance. So flame retardant DOPO derivative
applications are great. Due to DOPO derivatives Ⅲ has two phenolic
hydroxyl group, it can also be used as a curing agent for epoxy resin.
Compared with TBBA for traditional curing epoxy, epoxy resin cured by
it, Tg in General 40 ℃ higher, Td and charring rate is also higher. No
trickle down and produce black smoke during combustion phenomenon, so it
is very suitable as a circuit board substrates. If you have interest, read more here, thanks!
Source: https://www.okchem.com/news/something-halogen-free-flame-retardant.html
没有评论:
发表评论
注意:只有此博客的成员才能发布评论。