| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject polymer comprising a repeating unit substantially having a pyran cyclic structure and another repeating unit of (meta)acrylate, excellent in transparency, heat-resistance, low-water absorbability and mechanical strength, and lower in birefringence. SOLUTION: This objective copolymer comprising a repeating unit substantially shown by formula II ((n) is a positive integer) and repeating unit of (meta) acrylate is obtained by copolymerizing aα-substituted acrylate monomer [e.g. bis(α-hydroxymethyl methyl acrylate) ether] of formula I (R<1> is a 1-25C hydrocarbon, etc.), and (meta)acrylate (e.g. methyl methacrylate) by using a peroxide having >=2 of O-O bonds in one molecule as a polymerization initiator. As polymerized above, the monomer of formula I is subjected to cyclization reaction so that the pyran cyclic structure is formed. |
