Biodegradable polyesteretheramide wherein it contains: • from 5 to 80 mol % with respect to the sum of moles of compound 1+2 of an organic compound 1 with at least one aromatic or furan ring and two or more acid groups, their esters or anhydrides, or mixtures thereof, including under this designation both compounds obtained from petroleum and from natural sources; • from 20 to 95 mol % with respect to the sum of moles of compound 1+2 of an aliphatic or cycloaliphatic organic compound 2 with two or more acid groups, their esters or anhydrides, or mixtures thereof, including under this designation both compounds obtained from petroleum and from natural sources;, • from 20 to 300 mol % with respect to the sum of moles of compound 1+2 of an aliphatic, cycloaliphatic or aromatic organic compound 3 with at least one alcohol group, compound 3 including under this designation polyols, amino alcohol, carboxyl alcohol and optionally containing in its structure ether groups or mixtures of all of the mentioned compounds, including under this designation compounds obtained from petroleum and from natural sources; • from 0 to 2 mol % with respect to the sum of compounds 1+2+4, of an organic compound 4 containing sulphonic groups, including under this designation compounds obtained from petroleum and from natural sources; • from 0.02 to 5 mol % with respect to the sum of moles of compound 1+2 of a compound 5 with at least 3 groups capable of reacting with one or several types of the active groups present in the reaction mixture, wherein compound 5 is a polyether amine with at least 3 amino groups capable of reacting with one or several types of the active groups present in the reaction mixture; • from 0 to 10% by weight with respect to the weight of the polyesteretheramide obtained from the compound 1+2+3+4+5 of a compound 6 with at least 2 groups capable of reacting with the polyesteretheramide, including under this designation both compounds obtained from petroleum and from natural sources; • from 0 to 95 mol % with respect to the sum of moles of compound 1+2 of an aliphatic, cycloaliphatic or aromatic organic compound 7 with groups capable of forming amide bonds or esters in the reaction mixture, including under this designation both compounds obtained from petroleum and from natural sources; and • from 0 to 5% by weight with respect to the polyester amide, of a compound 8 acting as a catalyst. • from 5 to 80 mol % with respect to the sum of moles of compound 1+2 of an organic compound 1 with at least one aromatic or furan ring and two or more acid groups, their esters or anhydrides, or mixtures thereof, including under this designation both compounds obtained from petroleum and from natural sources; • from 20 to 95 mol % with respect to the sum of moles of compound 1+2 of an aliphatic or cycloaliphatic organic compound 2 with two or more acid groups, their esters or anhydrides, or mixtures thereof, including under this designation both compounds obtained from petroleum and from natural sources;, • from 20 to 300 mol % with respect to the sum of moles of compound 1+2 of an aliphatic, cycloaliphatic or aromatic organic compound 3 with at least one alcohol group, compound 3 including under this designation polyols, amino alcohol, carboxyl alcohol and optionally containing in its structure ether groups or mixtures of all of the mentioned compounds, including under this designation compounds obtained from petroleum and from natural sources; • from 0 to 2 mol % with respect to the sum of compounds 1+2+4, of an organic compound 4 containing sulphonic groups, including under this designation compounds obtained from petroleum and from natural sources; • from 0.02 to 5 mol % with respect to the sum of moles of compound 1+2 of a compound 5 with at least 3 groups capable of reacting with one or several types of the active groups present in the reaction mixture, wherein compound 5 is a polyether amine with at least 3 amino groups capable of reacting with one or several types of the active groups present in the reaction mixture; • from 0 to 10% by weight with respect to the weight of the polyesteretheramide obtained from the compound 1+2+3+4+5 of a compound 6 with at least 2 groups capable of reacting with the polyesteretheramide, including under this designation both compounds obtained from petroleum and from natural sources; • from 0 to 95 mol % with respect to the sum of moles of compound 1+2 of an aliphatic, cycloaliphatic or aromatic organic compound 7 with groups capable of forming amide bonds or esters in the reaction mixture, including under this designation both compounds obtained from petroleum and from natural sources; and • from 0 to 5% by weight with respect to the polyester amide, of a compound 8 acting as a catalyst.