FLUORINE-CONTAINING TRANSPARENT MATERIAL, AMORPHOUS PARTS-CONTAINING FLUORINE POLYMER BEARING CRYSTALLIZABLE FLUOROALKYL GROUPS AS SIDE CHAINS AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain the subject transparent fluorine-containing material that has a low refractive index with no unevenness and little transmission loss and is useful as an optical material or the like by using an amorphous polymer prepared by making a specific fluorine-containing polymer amorphous. SOLUTION: The objective transparent material comprises the amorphous main chain structure and the side chain structure bearing crystallizable fluoroalkyl groups or fluoroalkylene groups and is prepared by making the fluorine-containing polymer that manifests crystallinity originating from the side chains amorphous. In a preferred embodiment, this amorphous and transparent polymer has a fusion peak (ΔH) of 2.0 J/g according to DSC. The crystallizable fluoroalkyl groups are preferably the groups represented by the formula (Y is H, a halogen; m is >=0 and n is >=7 where m+n>=8). In a preferred embodiment, the fluorine-containing polymer that has caused crystallization due to the side chains is once melted with heat and then cooled down at a rate of >=1 deg.C/min and the like.