| 摘要 |
PCT No. PCT/JP80/00181 Sec. 371 Date May 20, 1981 Sec. 102(e) Date May 20, 1981 PCT Filed Aug. 12, 1980 PCT Pub. No. WO81/00814 PCT Pub. Date Apr. 2, 1981.This invention relates to a method and apparatus for removing volatile matter such as solvents and monomers from highly viscous materials such as synthetic polymers by the use of a falling-film evaporator. When a polymer composition containing a high concentration of the volatile matter, solvent and/or unreacted monomer, is preheated and then fed to a falling-film evaporator, the monomer reacts at a high temperature in the preheating, yielding its polymer of low molecular weight, and as a result the polymer quality deteriorates. When fed at a relatively low temperature, the polymer composition increases its viscosity with the vaporization of the solvent and/or monomer and becomes liable to partly solidify on account of the temperature drop due to the latent heat of vaporization, so that smooth treatment is difficult. This invention prevents the temperature drop as well as the reaction of the monomer, giving the polymer of high quality, by feeding the polymer composition of a relatively low temperature to a falling film evaporator and performing the heating of the polymer and the evaporation of the volatile matter simultaneously by supplying friction heat to the polymer composition within the clearances between the inner wall of the evaporator and the heating blades (19) attached to the outer ends of agitator blades (3), respectively.
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