Hypercrosslinking with diamine crosslinkers

A method of preparing a hypercrosslinked magnetic particle comprising a polymer matrix and at least one magnetic core (M), wherein the polymer matrix comprises at least one crosslinked polymer having at least one hypercrosslinking bond, wherein the hypercrosslinking bond consists of a molecule comprising at least two nitrogen atoms within its structure which are part of the hypercrosslinking bond, wherein the molecule comprising at least two nitrogen atoms within its structure has the general structure of formula I

• wherein
• x, y are independently 1 or 2;
• z is zero or 1;
• R1, R3 are independently selected from the group consisting of hydrogen, C1-C10-alkyl, C1-C10-alkenyl, C5-C10-cycloalkyl, C5-C12-aryl, C4-C10-heteroaryl and —(—O—CH2—CH2—)n—O—CH3 with n being an integer in the range of from 1 to 15, wherein each of R1, R3 may have at least one further substituent selected from the group consisting of hydrogen, C1-C5-alkyl, C5-C12-aryl, C4-C10-heteroaryl, and wherein R1 and R3 are separate or together with R2 form an aliphatic or aromatic ring system;
• R2 is selected from the group consisting of C1-C10-alkyl, which is optionally substituted with a —COOH or COO− group, C1-C10-alkenyl, C5-C10-cycloalkyl, C5-C12-aryl, C4-C10-heteroaryl and (—O—CH2—CH2—)n—O— with n being an integer in the range of from 1 to 15, wherein each cyclic structure having two or more ring systems has separated or annulated ring systems;
• the sinuous lines represent the crosslinked polymer;
• wherein the bonds connecting R2 with each nitrogen atom are independently selected from the group consisting of single, double and aromatic bond;
• and
• wherein the molecule comprising at least two nitrogen atoms within its structure having the general structure of formula I has at least one positive charge;
• the method comprising:
• (i) Providing a magnetic particle comprising a polymer matrix and at least one magnetic core (M), wherein the polymer matrix comprises at least one crosslinked polymer, which comprises at least two functional groups reactive towards amine groups;
• (ii) providing a molecule comprising at least two amine groups within its structure;
• (iii) reacting the groups reactive to amine groups of the magnetic particle provided in (i) with the amine groups of the molecule provided in (ii) thereby forming at least one hypercrosslinking bond;
• and thereby obtaining a hypercrosslinked magnetic particle,
• wherein the molecule comprising at least two nitrogen atoms within its structure has the general structure of formula II
• wherein
• x, y are independently 1 or 2;
• z is zero or 1;
• R1, R3 are independently selected from the group consisting of hydrogen, C1-C10-alkyl, C1-C10-alkenyl, C5-C10-cycloalkyl, C5-C12-aryl, C4-C10-heteroaryl and —(—O—CH2—CH2—)n—O—CH3 with n being an integer in the range of from 1 to 15, wherein each of R1, R3 may have at least one further substituent selected from the group consisting of hydrogen, C1-C5-alkyl, C5-C12-aryl, C4-C10-heteroaryl, and wherein R1 and R3 are separate or together form an aliphatic or aromatic ring system;
• R2 is selected from the group consisting of C1-C10-alkyl, which is optionally substituted with a —COOH or COO− group, C1-C10-alkenyl, C5-C10-cycloalkyl, C5-C12-aryl, C4-C10-heteroaryl and (—O—CH2—CH2—)n—O— with n being an integer in the range of from 1 to 15, wherein each cyclic structure having two or more ring systems has separated or annulated ring systems;
• R4, R5 are independently hydrogen or represent a free electron pair;
• wherein the bonds connecting R2 with each nitrogen atom are independently selected from the group consisting of single, double and aromatic bond.