Abstract: A plasticizer for halogen-containing resins which is composed of at least one compound expressed by the general formula ##STR1## wherein R.sub.1 represents an aromatic hydrocarbon group containing 1 or 2 aromatic rings or an alicyclic hydrocarbon group having 4 to 37 carbon atoms, R.sub.2.sup.1, R.sub.2.sup.2, R.sub.2.sup.3 and R.sub.2.sup.4 are identical or different and each represents an aliphatic hydrocarbon group having 2 to 17 carbon atoms, R.sub.3.sup.1, R.sub.3.sup.2, R.sub.3.sup.3 and R.sub.3.sup.4 are identical or different and each represents an aliphatic hydrocarbon group having 2 to 22 carbon atoms, an aromatic hydrocarbon group or a heterocyclic group, each of n.sub.1, n.sub.2, n.sub.3 and n.sub.4 is 0 or an integer of 1 to 20 and the sum of these is 1 to 20, and each of m.sub.1, m.sub.2, m.sub.3 and m.sub.4 is 0 or 1 and the sum of these is 1 to 4. The plastizer has superior thermal stability, processability and compatibility.

Abstract: A plasticizer for halogen-containing resins which is composed of at least one compound expressed by the general formula ##STR1## wherein R.sub.1 represents an aromatic hydrocarbon group containing 1 or 2 aromatic rings or an alicyclic hydrocarbon group having 4 to 37 carbon atoms, R.sub.2.sup.1, R.sub.2.sup.2, R.sub.2.sup.3 and R.sub.2.sup.4 are identical or different and each represents an aliphatic hydrocarbon group having 2 to 17 carbon atoms, R.sub.3.sup.1, R.sub.3.sup.2, R.sub.3.sup.3 and R.sub.3.sup.4 are identical or different and each represents an aliphatic hydrocarbon group having 2 to 22 carbon atoms, an aromatic hydrocarbon group or a heterocyclic group, each of n.sub.1, n.sub.2, n.sub.3 and n.sub.4 is 0 or an integer of 1 to 20 and the sum of these is 1 to 20, and each of m.sub.1, m.sub.2, m.sub.3 and m.sub.4 is 0 or 1 and the sum of these is 1 to 4. The plasticizer has superior thermal stability, processability and compatibility.