Abstract: The present invention relates to flame retardant polymer compositions comprising a flammable polymer and an amount of between 1% to 40% by weight of tetrabromodipentaerythritol as flame retardant agent. Optionally, synergistic flame retardant additives such as antimony oxide are incorporated in the compositions. The flammable polymers are selected from polyolefins, polyamides and styrenic resins or mixtues thereof. The flame retardant agent according to the present invention imparts to the polymer compositions improved thermal aging behaviour, thermal stability and non blooming property, compared with known flame retardant agents.

Abstract: Normally flammable organic polymers are rendered flame retardant by the incorporation of compounds corresponding to the formula: ##STR1## wherein each X is independently Br or Cl. The normally flammable organic polymers are selected from polyolefin, such as polypropylene, epoxy resins, unsaturated polyesters and styrene-based resins. The sulfite ester of tribromo neopentyl alcohol is preferred.

Abstract: Phosphonoacetals of the formula ##STR1## wherein R.sup.1 is an alkyl group having from 1-3 carbon atoms;R.sup.2 is a hydrogen atom or a cation such as NH.sub.4.sup.+, Na.sup.+, K.sup.+, Ca.sup.2+, Sn.sup.2+, Zn.sup.2+, Cd.sup.2+, Cu.sup.2+, and R.sup.1 ;n is an integer from 0 to 2;q is an integer from 1 to 3;R.sup.3 is a residue of a polyhydroxy compound having from 2-12 carbon atoms;Y and Y.sup.1 are each selected from the group consisting of hydrogen atoms, hydroxyl groups, carbinol groups, methyl halogens, methyl carbamoyls.