Provided is a complex obtained by reacting a polymer compound derivative obtained by modifying part of hydroxy groups or amino groups of a polymer compound having the hydroxy groups or amino groups with a compound represented by the following general formula (I) with one or more kinds of compounds represented by the following general formulae (II) to (V): (I) A-X--Si(Y).sub.nR.sub.3-n (where A, X, Y, R, and n are as defined in claim 1) ; (II) M(OR.sup.1).sub.nR.sup.2.sub.4-n; (III) Al(OR.sup.1).sub.pR.sup.2.sub.3-p; (IV) Mg(OR.sup.1).sub.gR.sup.2.sub.2-q (where M, R.sup.1, R.sup.2, n, p, and q are as defined in claim 1); and (V) (where R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are as defined in claim 1).