The invention discloses a preparing method of high reflectance rate
ethylene-vinyl-acetate
copolymer composition, which is characterized by containing the following components by weight proportion: 100 parts of
ethylene-vinyl-acetate
copolymer, 0.5-2 parts of cross-linking agent, 0.05-1 part of
antioxidant, 0.05-0.5 part of light stabilizer, 0.1-1.5 parts of
tackifier, 0.01-3 parts of fluorescent whitening agent and 0.5-15 parts of additive with a high
reflection function. The
ethylene-vinyl-acetate
copolymer and the other functional additives are performed with premixing, fusing extruding and
tape casting or calendaring for film forming, and finally are wound up to manufacture a high reflection rate
ethylene vinyl acetate copolymer (EVA) packaging glue film. The preparing method of high reflectance rate ethylene-vinyl-acetate
copolymer composition does not add organic
ultraviolet absorber, thereby reducing yellowing effect on the glue film caused by the
ultraviolet absorber. In addition, the preparing method of high reflectance rate ethylene-vinyl-acetate
copolymer composition improves yellowing resistance and
ultraviolet radiation resistance of the glue film by adding fluorescent whitening agent and high reflection additive. Simultaneously, reused ratio of light rays is increased, and finally long period service life of a photovoltaic
assembly can be prolonged and
photoelectric conversion efficiency of the photovoltaic
assembly can be improved.