Magnesium halide adducts, catalyst components and catalysts comprising the same, and preparation processes thereof

A magnesium halide adduct, comprising at least one compound of formula MgXY, at least one compound of formula ROH, methanol, at least one modifying agent chosen from DOE and o-hydroxy benzoates, and optionally water, wherein

• in the formula MgXY, X is a halogen, and Y, being independent of X, is chosen from a halogen, C1-C14 alkyl, C1-C14 alkoxy, C6-C14 aryl, and C6-C14 aryloxy;
• in the formula ROH, R is chosen from a C2-C12 alkyl, C3-C10 cycloalkyl, and C6-C10 aryl;
• the DOE is chosen from polyol esters of formula (I)
• wherein, R1 and R2, which may be identical or different and are independent of each other, are chosen from a halogen, a substituted or unsubstituted linear or branched C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 aralkyl, and C2-C20 alkenyl;
• R3-R6 and R1-R2k, which may be identical or different and are independent of each other, are chosen from hydrogen, a halogen, a substituted or unsubstituted linear or branched C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 aralkyl, C2-C20 alkenyl, C2-C20 ester groups, heteroatom-containing C1-C20 alkyl, heteroatom-containing C3-C20 cycloalkyl, heteroatom-containing C6-C20 aryl, heteroatom-containing C7-C20 aralkyl, heteroatom-containing C2-C20 alkenyl, wherein the heteroatom, is one or more chosen a halogen, nitrogen, oxygen, sulfur, silicon and phosphorus;
• alternatively, two or more of R3-R6 and R1-R2k are linked to form at least one ring structure chosen from saturated or unsaturated ring structures;
• the moiety in the parentheses “[ ]” represents k carbon atoms linked in sequence, and each of the carbon atoms is further linked to two substituents, so that there are k carbon atoms and 2k substituents R1, R2, R3 . . . R2k in the parentheses;
• and
• k is an integer ranging from 0 to 10, wherein when k=0, in the polyol ester of formula (I), the carbon atom substituted with R3 and R4 is directly linked to the carbon atom substituted with R5 and R6;
• and
• the o-hydroxy benzoate is of formula (II):
• wherein, R is chosen from a linear or branched C1-C12 alkyl, C3-C10 cycloalkyl, C6-C10 aryl, and C7-C10 arylalkyl.