9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide

DOPO (9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is a reactive phosphorus-containing compound widely used in the development of halogen-free flame retardants and high-performance polymer materials. Its molecular structure contains a highly reactive P–H bond, allowing DOPO to participate in various chemical reactions and serve as an important building block for synthesizing DOPO-based flame retardants and functional phosphorus compounds.

The product is typically supplied as a white powder or white flake. Its melting point is generally around 116–120°C, and it is insoluble in water while soluble in solvents such as benzene and toluene.

The main advantage of DOPO flame retardant chemistry is its reactive phosphorus structure. Rather than functioning only as a conventional physically blended additive, DOPO can be chemically modified or reacted with suitable functional compounds to produce reactive flame-retardant structures. This makes it particularly useful for applications where low migration and durable flame-retardant performance are important.

DOPO can also be chemically functionalized through reactions involving its reactive phosphorus center. These reactions allow manufacturers to develop a broad range of DOPO derivatives with different molecular structures and performance characteristics for specific polymer systems.

DOPO is widely used in epoxy resin flame-retardant systems, particularly for high-performance epoxy materials used in electronics and electrical applications. DOPO-derived flame retardants have been extensively studied for epoxy resins because they can provide flame-retardant performance while allowing the molecular structure of the flame-retardant system to be tailored to the requirements of the resin.

In the electronics industry, DOPO and its derivatives are used in flame-retardant epoxy systems for printed circuit boards (PCBs), copper-clad laminates and semiconductor encapsulation materials. These applications require a combination of flame resistance, thermal stability, electrical properties and long-term reliability.

DOPO is also used as a starting material for developing halogen-free reactive flame retardants for engineering plastics and other polymer systems. Its derivatives have been investigated for materials including polyesters, polyamides, polyurethanes and other high-performance polymers.

Beyond flame retardancy, DOPO-based chemistry can also be applied in specialized polymer formulations as a functional additive or intermediate. Certain DOPO-related compounds have been developed for applications such as color protection in ABS, AS, PP and resin systems, demonstrating the versatility of this phosphorus-containing chemical platform.

DOPO should be stored in a cool, dry and well-ventilated area, protected from moisture and incompatible materials. Appropriate packaging should be selected according to transportation requirements and intended storage conditions. Commercial packaging can be supplied according to customer requirements.