Layered double hydroxides organo-modified by 3-(4-hydroxyphenyl)propionic acid (HPPA), by 2-(4-hydroxyphenyl)ethylsulfonic acid or by a hydroxyphenylpropenoic acid, and to composite polymer materials having same. The composite materials are advantageously made of biosourced polymers such as poly(butylene succinate). These composite materials have improved properties over the polymers that make up the composition thereof, and over the composites of the prior art.