| 摘要 |
PURPOSE:To prepare a fluororesin which has a high elastic modulus and an improved resistance to heat and chemicals and does not flow even under heating above the m.p. by thermally treating a specific fluoropolymer. CONSTITUTION:A monomer of formula I (wherein X is F or Cl), a monomer of formula II [wherein Rf is a divalent org. group substd. by fluorine atoms; and Y is a carboxylic acid (deriv.) group] and, if necessary, a monomer of formula III (wherein Z is a monovalent org. group substd. by fluorine atoms) are polymerized in the presence of a polymn. initiator under 0.5-30kg/cm<2>G at 0-100 deg.C to give a fluoropolymer having a melt flow rate of 0.01-100 and comprising 70-99.9mol% units of formula IV, 0.1-20mol% units of formula V, and 0-10mol% units of formula VI. The fluoropolymer is thermally treated at a temp. higher than 200 deg.C and lower than the m.p. for 5hr or longer. |
