Phosphinate flame retardant and process for manufacture thereof

A phosphinate of the general formula (III-A), (III-B), (IV-A), (IV-B), (V-A), (V-B), (VI-A), (VI-B), (VI-C), or (VI-D):

• wherein the phosphinate is obtained by the reaction of at least one phosphinic acid of formula (I) with an oxirane of formula (II):
• wherein
• R1 and R2 are each, independently, H or a hydrocarbyl radical, provided that R1 and R2 may not both be H and the hydrocarbyl radical is selected from C1-C10 alkyl;
• and
• R3 is an alkylenyl group which is optionally substituted with a heteroatom selected from O, N, and S.

A process for the preparation of a phosphinate, comprising the step of reacting at least one phosphinic acid of formula (I) with an oxirane of formula (II):

• wherein
• R1 and R2 are each, independently, H or a hydrocarbyl radical, provided that R1 and R2 may not both be H and the hydrocarbyl radical is selected from C1-C10 alkyl;
• and
• R3 is an alkylenyl group which is optionally substituted with a heteroatom selected from O, N, and S.

A composition comprising at least one phosphinate of the general formula (III-A), (III-B), (IV-A), (IV-B), (V-A), (V-B), (VI-A), (VI-B), (VI-C), or (VI-D):

• wherein the at least one phosphinate is obtained by the reaction of at least one phosphinic acid of formula (I) with an oxirane of formula (II):
• wherein
• R1 and R2 are each, independently, H or a hydrocarbyl radical, provided that R1 and R2 may not both be H and the hydrocarbyl radical is selected from C1-C10 alkyl;
• and
• R3 is an alkylenyl group which is optionally substituted with a heteroatom selected from O, N, and S.