Phenol compounds and (co)polymers thereof

A copolymer according to Formula (II):

• wherein:
• a is 1 or more, b is 1 or more;
• R1 is selected from the group consisting of, optionally substituted, 2-pyridyl, 3-pyridyl and 4-pyridyl groups, wherein R1 is at position 2 or 3 of the phenol ring;
• R2 is selected from the group consisting of, optionally substituted, 2-pyridyl, 3-pyridyl, 4-pyridyl and phenyl groups, wherein R2 is at position 5 or 6 of the phenol ring;
• the phenol ring bearing R1 and R2 is optionally substituted at one or two positions, independently selected from positions 2, 3, 5 and 6, with a halogen atom, with an optionally substituted C6-C12 aryl groups or with an C1-C10 alkyl group;
• and
• one or two substituents selected from the group consisting of R3, R4, R5 and R6 are an, optionally substituted phenyl group, whereas the other substituents selected from the group R6 consisting of R3, R4, R5 and R6 are selected from the group of hydrogen, halogen, optionally substituted C6-C12 aryl groups and optionally substituted C1-C10 alkyl groups.