Preparation method of halogen-free flame retardant AN/MAA (acrylic nitrile/methyl acrylic acid) copolymer foam material

Abstract

The invention discloses a preparation method of a halogen-free flame retardant AN / MMA (acrylic nitrile / methyl acrylic acid) copolymer hard foam material. The main raw materials are AN and MAA; a nitrogen-phosphorus composite flame retardant is added while an initiator, a foaming agent, a crosslinking agent, a density control agent, a nucleating agent and a thickening agent are added at the same time, and an AN / MAA copolymer intermediate is obtained through free radical polymerization; and high-temperature foaming and thermal treatment are performed to obtain the flame retardant AN / MAA copolymer hard foam material. The oxygen index of the obtained halogen-free flame retardant AN / MAA copolymer hard foam material can exceed 33 according to a test. The foam material can be widely used as a filling material or sandwich material in the fields with certain requirements on flame retardance such as aerospace, high-speed trains, wind power, ships, medical treatment and the like.

Description

technical field [0001] The invention relates to a preparation method of a halogen-free flame-retardant AN / MAA copolymer foam material. Background technique [0002] AN / MAA copolymer foam is a rigid structural foam with excellent heat resistance, but the material itself does not have flame retardancy. With the increasing demand for rigid foam in the military and civilian markets, the flame retardancy of rigid foam has become a subject of increasing concern. [0003] Currently used flame retardants mainly include inorganic flame retardants such as antimony series, Al(OH) 3 , Mg(OH) 2 , red phosphorus, etc.; organic flame retardants include halogen and phosphorus. Halogenated flame retardants generate a large amount of smoke and produce toxic gases when burned, which is easy to cause secondary pollution. With the enhancement of people's awareness of environmental protection, the amount of halogenated flame retardants has become less and less. Although the amount of smoke ge...

AI Technical Summary

Problems solved by technology

Although the amount of smoke generated by inorganic flame retardants is very low and no toxic gases are produced when burned, the addition of large amounts often affects the physical and mechanical properties of the product

For the AN / MAA system, most of them are organic reagents, which are easy to cause phase separation. At the same time, if the foam made of red phosphorus is limited by the color problem, its scope of use is limited.

Phosphorus-based flame retardants have a small amount of smoke, but most of them are low-molecular phosphate esters, usually liquid, with high volatility and low heat resistance. It is easy to cause the decomposition of phosphorus flame retardants

When the nitrogen-based flame retardant is used alone, the flame retardant effect is poor