摘要 |
<p>An improved process is provided for the preparation of esters of polyhalophthalic acids, polyhalobenzoic acids, and polyhalophthalic anhydride useful as flame retardants for thermoplastic and thermosetting resins, which comprises the reaction of the above acids or anhydride with alcohols in the presence of certain metal and metallorganic compounds as catalysts. Also provided are certain esters per se.</p> |