Partial block polyimide-polysiloxane copolymer, making method, and resin composition comprising the copolymer

A partial block polyimide-polysiloxane copolymer comprising repeat unit structures having the following structural formulae (2) and (8):

• wherein X is at least one aromatic ring-containing tetravalent organic radical selected from the group consisting of:
• Y2 is a divalent organic radical having the structural formula (3), Y3 is a divalent organic radical having the structural formula (9), Y2 and Y3 are contained in the copolymer in molar amounts y2 and y3, respectively, which satisfy
• y2/(y2+y3)=0.5 to 0.01 and
• y3/(y2+y3)=0.5 to 0.99,
• m is a weight average value of 9.1 to 50, j is a weight average value of 8.8 to 50,
• wherein R1 is a divalent organic radical of 3 to 9 carbon atoms, R2 and R3 are each independently a substituted or unsubstituted, monovalent hydrocarbon radical of 1 to 8 carbon atoms, and n is an integer of 1 to 150,
• wherein A is a radical selected from the following group [9a]:
• group [9a]
• B is a radical selected from the following group [9b]:
• group [9b]
• R is each independently a hydrogen atom, halogen atom or substituted or unsubstituted, monovalent hydrocarbon radical of 1 to 8 carbon atoms, and k is a natural number of 1 to 5.