FR FOAM & FR CHEMICALS
TCPP (tris-chloro-propyl-phosphate) is the same thing as TMCP (tris-mono-chloro-propyl-phosphate).
TDCP (tris-dichloro-propyl-phosphate) contains twice more chloride and is therefore more efficient than TMCP-TCPP and more permanent in the foam with less scorch.
TCPP, TDCP and V6 are not reactive and can be used in HR without any problem. Except with low densities where you need more water and TDI to compensate (keep the same density) for the inclusion of FR. Therefore the exotherm will be higher and there will be scorch.
Do not forget to use an FR silicone for polyether foams; otherwise you'll ruin the FR effect.
TMCP/TCPP will give you more scorch than V6 which in turn will give you more scorch than TDCP.
TDCP & V6 are more permanent into the foam because their molecular weight is higher, TCPP tends to get out of foam with time.
TCPP can absorb heat from the dilution/heat sink property. So the FR will reduce the temperature of the exotherm. This gives a substantial reduction of 5 to 10 degrees. The V6 do not have the same advantage.
TCPP also acts a cell opener. So it is used intensively in HR foam where it behaves very well when used in conjunction with melamine. As such, it can pass the most difficult tests, the CRIB 5.
However, without Melamine, TCPP falters and fails these stringent tests (even VMS302 which is commonly used in the automotive industry).
TCPP affects the FR performance because it is a natural cell opener; the foam to be fire retarded needs to be not open but closed. That is where the V6 do not require the foamer to increase the stannous between 50 to 75%.
TCPP should not be used in low density below density 30 conventional foam because of three things, 1) it contributes to scorch more than the rest, 2) it is less permanent than the rest and, 3) it opens the cells more than the rest. As a result, its FR properties are lower than the rest. V6 will all be better at density below 30.
TCPP is recommended for melamine based High Resiliency foam.
